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class="breadcrumbs__link" href="/"><svg viewBox="0 0 24 24" class="breadcrumbHomeIcon_YNFT"><path d="M10 19v-5h4v5c0 .55.45 1 1 1h3c.55 0 1-.45 1-1v-7h1.7c.46 0 .68-.57.33-.87L12.67 3.6c-.38-.34-.96-.34-1.34 0l-8.36 7.53c-.34.3-.13.87.33.87H5v7c0 .55.45 1 1 1h3c.55 0 1-.45 1-1z" fill="currentColor"></path></svg></a></li><li class="breadcrumbs__item"><span class="breadcrumbs__link">🔄 Replication</span><meta itemprop="position" content="1"></li><li itemscope="" itemprop="itemListElement" itemtype="https://schema.org/ListItem" class="breadcrumbs__item breadcrumbs__item--active"><span class="breadcrumbs__link" itemprop="name">⚙️ Replication Protocol</span><meta itemprop="position" content="2"></li></ul></nav><div class="tocCollapsible_ETCw theme-doc-toc-mobile tocMobile_ITEo"><button type="button" class="clean-btn tocCollapsibleButton_TO0P">On this page</button></div><div class="theme-doc-markdown markdown"><header><h1>RxDB Database Replication Protocol</h1></header>
<p>The RxDB replication protocol provides the ability to replicate the database state in <strong>realtime</strong> between the clients and the server.</p>
<p>The backend server does not have to be a RxDB instance; you can build a replication with <strong>any infrastructure</strong>.
For example you can replicate with a custom GraphQL endpoint or a <a href="/replication-http.html">http server</a> on top of a PostgreSQL database.</p>
<p>The replication is made to support the <a href="/offline-first.html">Offline-First</a> paradigm, so that when the client goes offline, the RxDB database can still read and write locally and will continue the replication when the client goes online again.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="design-decisions">Design Decisions<a href="#design-decisions" class="hash-link" aria-label="Direct link to Design Decisions" title="Direct link to Design Decisions"></a></h2>
<p>In contrast to other database replication protocols, the RxDB replication protocol is optimized for client side apps.</p>
<ul>
<li>
<p><strong>Backend-Agnostic</strong>: Because it relies on a clearly defined interface and simple methods, the RxDB replication protocol can integrate with any existing backend infrastructure. There's no need to set up a special server or database solution - just implement the pullHandler, pushHandler, and pullStream according to your existing architecture.</p>
</li>
<li>
<p><strong>Optimized for Browser Environments</strong>: The protocol takes advantage of bulk document handling in one go, which drastically reduces network overhead. By grouping updates and fetches into batches, client apps can push and pull large sets of changes efficiently, keeping your UI responsive.</p>
</li>
<li>
<p><strong>Straightforward Implementation</strong>: The RxDB replication logic mirrors a "git-like" approach for merging and conflict resolution, making it easy to understand. The steps are clear: you pull updates, push local changes, and handle conflicts if both sides have updated the same document.</p>
</li>
<li>
<p><strong>Offline-First Support</strong>: By incorporating conflict handling at the client side, the protocol fully supports offline-first apps. Users can continue making changes while offline, and those updates will sync seamlessly once a connection is reestablished - all without risking data loss or having undefined behavior.</p>
</li>
</ul>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="replication-protocol-on-the-document-level">Replication protocol on the document level<a href="#replication-protocol-on-the-document-level" class="hash-link" aria-label="Direct link to Replication protocol on the document level" title="Direct link to Replication protocol on the document level"></a></h2>
<p>On the RxDocument level, the replication works like git, where the fork/client contains all new writes and must be merged with the master/server before it can push its new state to the master/server.</p>
<div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">A---B-----------D master/server state</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> \ /</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> B---C---D fork/client state</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<ul>
<li>The client pulls the latest state <code>B</code> from the master.</li>
<li>The client does some changes <code>C+D</code>.</li>
<li>The client pushes these changes to the master by sending the latest known master state <code>B</code> and the new client state <code>D</code> of the document.</li>
<li>If the master state is equal to the latest master <code>B</code> state of the client, the new client state <code>D</code> is set as the latest master state.</li>
<li>If the master also had changes and so the latest master change is different then the one that the client assumes, we have a conflict that has to be resolved on the client.</li>
</ul>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="replication-protocol-on-the-transfer-level">Replication protocol on the transfer level<a href="#replication-protocol-on-the-transfer-level" class="hash-link" aria-label="Direct link to Replication protocol on the transfer level" title="Direct link to Replication protocol on the transfer level"></a></h2>
<p>When document states are transferred, all handlers use batches of documents for better performance.
The server <strong>must</strong> implement the following methods to be compatible with the replication:</p>
<ul>
<li><strong>pullHandler</strong> Get the last checkpoint (or null) as input. Returns all documents that have been written <strong>after</strong> the given checkpoint. Also returns the checkpoint of the latest written returned document.</li>
<li><strong>pushHandler</strong> a method that can be called by the client to send client side writes to the master. It gets an array with the <code>assumedMasterState</code> and the <code>newForkState</code> of each document write as input. It must return an array that contains the master document states of all conflicts. If there are no conflicts, it must return an empty array.</li>
<li><strong>pullStream</strong> an observable that emits batches of all master writes and the latest checkpoint of the write batches.</li>
</ul>
<div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain"> +--------+ +--------+ </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | | pullHandler() | |</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | |---------------------> | | </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | | | | </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | | | |</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | Client | pushHandler() | Server |</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | |---------------------> | | </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | | | |</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | | pullStream$ | | </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> | | <-------------------------| | </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> +--------+ +--------+</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<p>The replication runs in two <strong>different modes</strong>:</p>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="checkpoint-iteration">Checkpoint iteration<a href="#checkpoint-iteration" class="hash-link" aria-label="Direct link to Checkpoint iteration" title="Direct link to Checkpoint iteration"></a></h3>
<p>On first initial replication, or when the client comes online again, a checkpoint based iteration is used to catch up with the server state.
A checkpoint is a subset of the fields of the last pulled document. When the checkpoint is send to the backend via <code>pullHandler()</code>, the backend must be able to respond with all documents that have been written <strong>after</strong> the given checkpoint.
For example if your documents contain an <code>id</code> and an <code>updatedAt</code> field, these two can be used as checkpoint.</p>
<p>When the checkpoint iteration reaches the last checkpoint, where the backend returns an empty array because there are no newer documents, the replication will automatically switch to the <code>event observation</code> mode.</p>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="event-observation">Event observation<a href="#event-observation" class="hash-link" aria-label="Direct link to Event observation" title="Direct link to Event observation"></a></h3>
<p>While the client is connected to the backend, the events from the backend are observed via <code>pullStream$</code> and persisted to the client.</p>
<p>If your backend for any reason is not able to provide a full <code>pullStream$</code> that contains all events and the checkpoint, you can instead only emit <code>RESYNC</code> events that tell RxDB that anything unknown has changed on the server and it should run the pull replication via <a href="#checkpoint-iteration">checkpoint iteration</a>.</p>
<p>When the client goes offline and online again, it might happen that the <code>pullStream$</code> has missed out some events. Therefore the <code>pullStream$</code> should also emit a <code>RESYNC</code> event each time the client reconnects, so that the client can become in sync with the backend via the <a href="#checkpoint-iteration">checkpoint iteration</a> mode.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="data-layout-on-the-server">Data layout on the server<a href="#data-layout-on-the-server" class="hash-link" aria-label="Direct link to Data layout on the server" title="Direct link to Data layout on the server"></a></h2>
<p>To use the replication you first have to ensure that:</p>
<ul>
<li>
<p><strong>documents are deterministic sortable by their last write time</strong></p>
<p><em>deterministic</em> means that even if two documents have the same <em>last write time</em>, they have a predictable sort order.
This is most often ensured by using the <em>primaryKey</em> as second sort parameter as part of the checkpoint.</p>
</li>
<li>
<p><strong>documents are never deleted, instead the <code>_deleted</code> field is set to <code>true</code>.</strong></p>
<p>This is needed so that the deletion state of a document exists in the database and can be replicated with other instances. If your backend uses a different field to mark deleted documents, you have to transform the data in the push/pull handlers or with the modifiers.</p>
</li>
</ul>
<p>For example if your documents look like this:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> docData </span><span class="token operator">=</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string-property property">"id"</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"foobar"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string-property property">"name"</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"Alice"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string-property property">"lastName"</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">"Wilson"</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Contains the last write timestamp</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * so all documents writes can be sorted by that value</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * when they are fetched from the remote instance.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string-property property">"updatedAt"</span><span class="token operator">:</span><span class="token plain"> </span><span class="token number">1564483474</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Instead of physically deleting documents,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * a deleted document gets replicated.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string-property property">"_deleted"</span><span class="token operator">:</span><span class="token plain"> </span><span class="token boolean">false</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<p>Then your data is always sortable by <code>updatedAt</code>. This ensures that when RxDB fetches 'new' changes via <code>pullHandler()</code>, it can send the latest <code>updatedAt+id</code> checkpoint to the remote endpoint and then receive all newer documents.</p>
<p>By default, the field is <code>_deleted</code>. If your remote endpoint uses a different field to mark deleted documents, you can set the <code>deletedField</code> in the replication options which will automatically map the field on all pull and push requests.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="conflict-handling">Conflict handling<a href="#conflict-handling" class="hash-link" aria-label="Direct link to Conflict handling" title="Direct link to Conflict handling"></a></h2>
<p>When multiple clients (or the server) modify the same document at the same time (or when they are offline), it can happen that a conflict arises during the replication.</p>
<div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">A---B1---C1---X master/server state</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> \ /</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> B1---C2 fork/client state</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<p>In the case above, the client would tell the master to move the document state from <code>B1</code> to <code>C2</code> by calling <code>pushHandler()</code>. But because the actual master state is <code>C1</code> and not <code>B1</code>, the master would reject the write by sending back the actual master state <code>C1</code>.
<strong>RxDB resolves all conflicts on the client</strong> so it would call the conflict handler of the <code>RxCollection</code> and create a new document state <code>D</code> that can then be written to the master.</p>
<div class="codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-text codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">A---B1---C1---X---D master/server state</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> \ / \ /</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> B1---C2---D fork/client state</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<p>The default conflict handler will always drop the fork state and use the master state. This ensures that clients that are offline for a very long time, do not accidentally overwrite other peoples changes when they go online again.
You can specify a custom conflict handler by setting the property <code>conflictHandler</code> when calling <code>addCollection()</code>.</p>
<p>Learn how to create a <a href="/transactions-conflicts-revisions.html#custom-conflict-handler">custom conflict handler</a>.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="replicaterxcollection">replicateRxCollection()<a href="#replicaterxcollection" class="hash-link" aria-label="Direct link to replicateRxCollection()" title="Direct link to replicateRxCollection()"></a></h2>
<p>You can start the replication of a single <code>RxCollection</code> by calling <code>replicateRxCollection()</code> like in the following:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"> replicateRxCollection </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">from</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'rxdb/plugins/replication'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">import</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> lastOfArray</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">from</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'rxdb'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> replicationState </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">replicateRxCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> collection</span><span class="token operator">:</span><span class="token plain"> myRxCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * An id for the replication to identify it</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * and so that RxDB is able to resume the replication on app reload.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If you replicate with a remote server, it is recommended to put the</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * server url into the replicationIdentifier.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> replicationIdentifier</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'my-rest-replication-to-https://example.com/api/sync'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * By default it will do an ongoing realtime replication.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * By settings live: false the replication will run once until the local state</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * is in sync with the remote state, then it will cancel itself.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * (optional), default is true.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> live</span><span class="token operator">:</span><span class="token plain"> </span><span class="token boolean">true</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Time in milliseconds after when a failed backend request</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * has to be retried.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * This time will be skipped if a offline->online switch is detected</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * via navigator.onLine</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * (optional), default is 5 seconds.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> retryTime</span><span class="token operator">:</span><span class="token plain"> </span><span class="token number">5</span><span class="token plain"> </span><span class="token operator">*</span><span class="token plain"> </span><span class="token number">1000</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * When multiInstance is true, like when you use RxDB in multiple browser tabs,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * the replication should always run in only one of the open browser tabs.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If waitForLeadership is true, it will wait until the current instance is leader.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If waitForLeadership is false, it will start replicating, even if it is not leader.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * [default=true]</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> waitForLeadership</span><span class="token operator">:</span><span class="token plain"> </span><span class="token boolean">true</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If this is set to false,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * the replication will not start automatically</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * but will wait for replicationState.start() being called.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * (optional), default is true</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> autoStart</span><span class="token operator">:</span><span class="token plain"> </span><span class="token boolean">true</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Custom deleted field, the boolean property of the document data that</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * marks a document as being deleted.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If your backend uses a different fieldname then '_deleted', set the fieldname here.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * RxDB will still store the documents internally with '_deleted', setting this field</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * only maps the data on the data layer.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If a custom deleted field contains a non-boolean value, the deleted state</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * of the documents depends on if the value is truthy or not. So instead of providing a boolean * * deleted value, you could also work with using a 'deletedAt' timestamp instead.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * [default='_deleted']</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> deletedField</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'deleted'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Optional,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * only needed when you want to replicate local changes to the remote instance.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> push</span><span class="token operator">:</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Push handler</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">async</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">handler</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">docs</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Push the local documents to a remote REST server.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> rawResponse </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">fetch</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'https://example.com/api/sync/push'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> method</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'POST'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> headers</span><span class="token operator">:</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string-property property">'Accept'</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'application/json'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token string-property property">'Content-Type'</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'application/json'</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> body</span><span class="token operator">:</span><span class="token plain"> </span><span class="token constant" style="color:rgb(189, 147, 249)">JSON</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">stringify</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"> docs </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Contains an array with all conflicts that appeared during this push.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If there were no conflicts, return an empty array.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> response </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> rawResponse</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">json</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">return</span><span class="token plain"> response</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Batch size, optional</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Defines how many documents will be given to the push handler at once.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> batchSize</span><span class="token operator">:</span><span class="token plain"> </span><span class="token number">5</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Modifies all documents before they are given to the push handler.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Can be used to swap out a custom deleted flag instead of the '_deleted' field.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * If the push modifier return null, the document will be skipped and not send to the remote.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Notice that the modifier can be called multiple times and should not contain any side effects.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * (optional)</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token function-variable function" style="color:rgb(80, 250, 123)">modifier</span><span class="token operator">:</span><span class="token plain"> d </span><span class="token operator">=></span><span class="token plain"> d</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Optional,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * only needed when you want to replicate remote changes to the local state.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> pull</span><span class="token operator">:</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Pull handler</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">async</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">handler</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">lastCheckpoint</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> batchSize</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> minTimestamp </span><span class="token operator">=</span><span class="token plain"> lastCheckpoint </span><span class="token operator">?</span><span class="token plain"> lastCheckpoint</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">updatedAt </span><span class="token operator">:</span><span class="token plain"> </span><span class="token number">0</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * In this example we replicate with a remote REST server</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> response </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">fetch</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token template-string template-punctuation string" style="color:rgb(255, 121, 198)">`</span><span class="token template-string string" style="color:rgb(255, 121, 198)">https://example.com/api/sync/?minUpdatedAt=</span><span class="token template-string interpolation interpolation-punctuation punctuation" style="color:rgb(248, 248, 242)">${</span><span class="token template-string interpolation">minTimestamp</span><span class="token template-string interpolation interpolation-punctuation punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token template-string string" style="color:rgb(255, 121, 198)">&limit=</span><span class="token template-string interpolation interpolation-punctuation punctuation" style="color:rgb(248, 248, 242)">${</span><span class="token template-string interpolation">batchSize</span><span class="token template-string interpolation interpolation-punctuation punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token template-string template-punctuation string" style="color:rgb(255, 121, 198)">`</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> documentsFromRemote </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> response</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">json</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">return</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Contains the pulled documents from the remote.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Not that if documentsFromRemote.length < batchSize,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * then RxDB assumes that there are no more un-replicated documents</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * on the backend, so the replication will switch to 'Event observation' mode.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> documents</span><span class="token operator">:</span><span class="token plain"> documentsFromRemote</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * The last checkpoint of the returned documents.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * On the next call to the pull handler,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * this checkpoint will be passed as 'lastCheckpoint'</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> checkpoint</span><span class="token operator">:</span><span class="token plain"> documentsFromRemote</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">length </span><span class="token operator">===</span><span class="token plain"> </span><span class="token number">0</span><span class="token plain"> </span><span class="token operator">?</span><span class="token plain"> lastCheckpoint </span><span class="token operator">:</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> id</span><span class="token operator">:</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">lastOfArray</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">documentsFromRemote</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">id</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> updatedAt</span><span class="token operator">:</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">lastOfArray</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">documentsFromRemote</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">updatedAt</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> batchSize</span><span class="token operator">:</span><span class="token plain"> </span><span class="token number">10</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Modifies all documents after they have been pulled</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * but before they are used by RxDB.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Notice that the modifier can be called multiple times and should not contain any side effects.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * (optional)</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token function-variable function" style="color:rgb(80, 250, 123)">modifier</span><span class="token operator">:</span><span class="token plain"> d </span><span class="token operator">=></span><span class="token plain"> d</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Stream of the backend document writes.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * See below.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * You only need a stream$ when you have set live=true</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> stream$</span><span class="token operator">:</span><span class="token plain"> pullStream$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">asObservable</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Creating the pull stream for realtime replication.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Here we use a websocket but any other way of sending data to the client can be used,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * like long polling or server-sent events.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> pullStream$ </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">new</span><span class="token plain"> </span><span class="token class-name">Subject</span><span class="token class-name operator"><</span><span class="token class-name">RxReplicationPullStreamItem</span><span class="token class-name operator"><</span><span class="token class-name builtin" style="color:rgb(189, 147, 249)">any</span><span class="token class-name punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token class-name"> </span><span class="token class-name builtin" style="color:rgb(189, 147, 249)">any</span><span class="token class-name operator">>></span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">let</span><span class="token plain"> firstOpen </span><span class="token operator">=</span><span class="token plain"> </span><span class="token boolean">true</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">function</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">connectSocket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> socket </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">new</span><span class="token plain"> </span><span class="token class-name">WebSocket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'wss://example.com/api/sync/stream'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * When the backend sends a new batch of documents+checkpoint,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * emit it into the stream$.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * event.data must look like this</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><span class="token doc-comment comment punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * documents: [</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><span class="token doc-comment comment punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * id: 'foobar',</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * _deleted: false,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * updatedAt: 1234</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><span class="token doc-comment comment punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * ],</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * checkpoint: </span><span class="token doc-comment comment punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * id: 'foobar',</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * updatedAt: 1234</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><span class="token doc-comment comment punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * </span><span class="token doc-comment comment punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> socket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function-variable function" style="color:rgb(80, 250, 123)">onmessage</span><span class="token plain"> </span><span class="token operator">=</span><span class="token plain"> event </span><span class="token operator">=></span><span class="token plain"> pullStream$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">next</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">event</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">data</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * Automatically reconnect the socket on close and error.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> socket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function-variable function" style="color:rgb(80, 250, 123)">onclose</span><span class="token plain"> </span><span class="token operator">=</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">=></span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">connectSocket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> socket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function-variable function" style="color:rgb(80, 250, 123)">onerror</span><span class="token plain"> </span><span class="token operator">=</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">=></span><span class="token plain"> socket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">close</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> socket</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function-variable function" style="color:rgb(80, 250, 123)">onopen</span><span class="token plain"> </span><span class="token operator">=</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">=></span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">if</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">firstOpen</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> firstOpen </span><span class="token operator">=</span><span class="token plain"> </span><span class="token boolean">false</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">else</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token doc-comment comment" style="color:rgb(98, 114, 164)">/**</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * When the client is offline and goes online again,</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * it might have missed out events that happened on the server.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * So we have to emit a RESYNC so that the replication goes</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * into 'Checkpoint iteration' mode until the client is in sync</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> * and then it will go back into 'Event observation' mode again.</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token doc-comment comment" style="color:rgb(98, 114, 164)"> */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> pullStream$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">next</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'RESYNC'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span></code></pre><div 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<h2 class="anchor anchorWithStickyNavbar_LWe7" id="multi-tab-support">Multi Tab support<a href="#multi-tab-support" class="hash-link" aria-label="Direct link to Multi Tab support" title="Direct link to Multi Tab support"></a></h2>
<p>For better performance, the replication runs only in one instance when RxDB is used in multiple browser tabs or Node.js processes.
By setting <code>waitForLeadership: false</code> you can enforce that each tab runs its own replication cycles.
If used in a multi instance setting, so when at database creation <code>multiInstance: false</code> was not set,
you need to import the <a href="/leader-election.html">leader election plugin</a> so that RxDB can know how many instances exist and which browser tab should run the replication.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="error-handling">Error handling<a href="#error-handling" class="hash-link" aria-label="Direct link to Error handling" title="Direct link to Error handling"></a></h2>
<p>When sending a document to the remote fails for any reason, RxDB will send it again in a later point in time.
This happens for <strong>all</strong> errors. The document write could have already reached the remote instance and be processed, while only the answering fails.
The remote instance must be designed to handle this properly and to not crash on duplicate data transmissions.
Depending on your use case, it might be ok to just write the duplicate document data again.
But for a more resilient error handling you could compare the last write timestamps or add a unique write id field to the document. This field can then be used to detect duplicates and ignore re-send data.</p>
<p>Also the replication has an <code>.error$</code> stream that emits all <code>RxError</code> objects that arise during replication.
Notice that these errors contain an inner <code>.parameters.errors</code> field that contains the original error. Also they contain a <code>.parameters.direction</code> field that indicates if the error was thrown during <code>pull</code> or <code>push</code>. You can use these to properly handle errors. For example when the client is outdated, the server might respond with a <code>426 Upgrade Required</code> error code that can then be used to force a page reload.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">replicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">error$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">error</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">=></span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">if</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> error</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">parameters</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">errors </span><span class="token operator">&&</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> error</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">parameters</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">errors</span><span class="token punctuation" style="color:rgb(248, 248, 242)">[</span><span class="token number">0</span><span class="token punctuation" style="color:rgb(248, 248, 242)">]</span><span class="token plain"> </span><span class="token operator">&&</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> error</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">parameters</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">errors</span><span class="token punctuation" style="color:rgb(248, 248, 242)">[</span><span class="token number">0</span><span class="token punctuation" style="color:rgb(248, 248, 242)">]</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">code </span><span class="token operator">===</span><span class="token plain"> </span><span class="token number">426</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">// client is outdated -> enforce a page reload</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> location</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">reload</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="security">Security<a href="#security" class="hash-link" aria-label="Direct link to Security" title="Direct link to Security"></a></h2>
<p>Be aware that client side clocks can never be trusted. When you have a client-backend replication, the backend should overwrite the <code>updatedAt</code> timestamp or use another field, when it receives the change from the client.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="rxreplicationstate">RxReplicationState<a href="#rxreplicationstate" class="hash-link" aria-label="Direct link to RxReplicationState" title="Direct link to RxReplicationState"></a></h2>
<p>The function <code>replicateRxCollection()</code> returns a <code>RxReplicationState</code> that can be used to manage and observe the replication.</p>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="observable">Observable<a href="#observable" class="hash-link" aria-label="Direct link to Observable" title="Direct link to Observable"></a></h3>
<p>To observe the replication, the <code>RxReplicationState</code> has some <code>Observable</code> properties:</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token comment" style="color:rgb(98, 114, 164)">// emits each document that was received from the remote</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">received$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">doc </span><span class="token operator">=></span><span class="token plain"> </span><span class="token builtin" style="color:rgb(189, 147, 249)">console</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">dir</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">doc</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// emits each document that was send to the remote</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">sent$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">doc </span><span class="token operator">=></span><span class="token plain"> </span><span class="token builtin" style="color:rgb(189, 147, 249)">console</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">dir</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">doc</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// emits all errors that happen when running the push- & pull-handlers.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">error$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">error </span><span class="token operator">=></span><span class="token plain"> </span><span class="token builtin" style="color:rgb(189, 147, 249)">console</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">dir</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">error</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// emits true when the replication was canceled, false when not.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">canceled$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">bool </span><span class="token operator">=></span><span class="token plain"> </span><span class="token builtin" style="color:rgb(189, 147, 249)">console</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">dir</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">bool</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// emits true when a replication cycle is running, false when not.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">active$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">bool </span><span class="token operator">=></span><span class="token plain"> </span><span class="token builtin" style="color:rgb(189, 147, 249)">console</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">dir</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">bool</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="awaitinitialreplication">awaitInitialReplication()<a href="#awaitinitialreplication" class="hash-link" aria-label="Direct link to awaitInitialReplication()" title="Direct link to awaitInitialReplication()"></a></h3>
<p>With <code>awaitInitialReplication()</code> you can await the initial replication that is done when a full replication cycle was successful finished for the first time. The returned promise will never resolve if you cancel the replication before the initial replication can be done.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">awaitInitialReplication</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="awaitinsync">awaitInSync()<a href="#awaitinsync" class="hash-link" aria-label="Direct link to awaitInSync()" title="Direct link to awaitInSync()"></a></h3>
<p>Returns a <code>Promise</code> that resolves when:</p>
<ul>
<li><code>awaitInitialReplication()</code> has emitted.</li>
<li>All local data is replicated with the remote.</li>
<li>No replication cycle is running or in retry-state.</li>
</ul>
<div class="theme-admonition theme-admonition-warning admonition_xJq3 alert alert--warning"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 16 16"><path fill-rule="evenodd" d="M8.893 1.5c-.183-.31-.52-.5-.887-.5s-.703.19-.886.5L.138 13.499a.98.98 0 0 0 0 1.001c.193.31.53.501.886.501h13.964c.367 0 .704-.19.877-.5a1.03 1.03 0 0 0 .01-1.002L8.893 1.5zm.133 11.497H6.987v-2.003h2.039v2.003zm0-3.004H6.987V5.987h2.039v4.006z"></path></svg></span>warning</div><div class="admonitionContent_BuS1"><p>When <code>multiInstance: true</code> and <code>waitForLeadership: true</code> and another tab is already running the replication, <code>awaitInSync()</code> will not resolve until the other tab is closed and the replication starts in this tab.</p><div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">awaitInSync</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div>
<div class="theme-admonition theme-admonition-warning admonition_xJq3 alert alert--warning"><div class="admonitionHeading_Gvgb"><span class="admonitionIcon_Rf37"><svg viewBox="0 0 16 16"><path fill-rule="evenodd" d="M8.893 1.5c-.183-.31-.52-.5-.887-.5s-.703.19-.886.5L.138 13.499a.98.98 0 0 0 0 1.001c.193.31.53.501.886.501h13.964c.367 0 .704-.19.877-.5a1.03 1.03 0 0 0 .01-1.002L8.893 1.5zm.133 11.497H6.987v-2.003h2.039v2.003zm0-3.004H6.987V5.987h2.039v4.006z"></path></svg></span>warning</div><div class="admonitionContent_BuS1"><h4 class="anchor anchorWithStickyNavbar_LWe7" id="awaitinitialreplication-and-awaitinsync-should-not-be-used-to-block-the-application"><code>awaitInitialReplication()</code> and <code>awaitInSync()</code> should not be used to block the application<a href="#awaitinitialreplication-and-awaitinsync-should-not-be-used-to-block-the-application" class="hash-link" aria-label="Direct link to awaitinitialreplication-and-awaitinsync-should-not-be-used-to-block-the-application" title="Direct link to awaitinitialreplication-and-awaitinsync-should-not-be-used-to-block-the-application"></a></h4><p>A common mistake in RxDB usage is when developers want to block the app usage until the application is in sync.
Often they just <code>await</code> the promise of <code>awaitInitialReplication()</code> or <code>awaitInSync()</code> and show a loading spinner until they resolve. This is dangerous and should not be done because:</p><ul>
<li>When <code>multiInstance: true</code> and <code>waitForLeadership: true (default)</code> and another tab is already running the replication, <code>awaitInitialReplication()</code> will not resolve until the other tab is closed and the replication starts in this tab.</li>
<li>Your app can no longer be started when the device is offline because there the <code>awaitInitialReplication()</code> will never resolve and the app cannot be used.</li>
</ul><p>Instead you should store the last in-sync time in a <a href="/rx-local-document.html">local document</a> and observe its value on all instances.</p><p>For example if you want to block clients from using the app if they have not been in sync for the last 24 hours, you could use this code:</p><div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// update last-in-sync-flag each time replication is in sync</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">insertLocal</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'last-in-sync'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"> time</span><span class="token operator">:</span><span class="token plain"> </span><span class="token number">0</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">catch</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">// ensure flag exists</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">myReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">active$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">pipe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">mergeMap</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">async</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">=></span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">awaitInSync</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">upsertLocal</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'last-in-sync'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"> time</span><span class="token operator">:</span><span class="token plain"> Date</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">now</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// observe the flag and toggle loading spinner</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">showLoadingSpinner</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> oneDay </span><span class="token operator">=</span><span class="token plain"> </span><span class="token number">1000</span><span class="token plain"> </span><span class="token operator">*</span><span class="token plain"> </span><span class="token number">60</span><span class="token plain"> </span><span class="token operator">*</span><span class="token plain"> </span><span class="token number">60</span><span class="token plain"> </span><span class="token operator">*</span><span class="token plain"> </span><span class="token number">24</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">firstValueFrom</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> myCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">getLocal$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'last-in-sync'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">pipe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">filter</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">d </span><span class="token operator">=></span><span class="token plain"> d</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">get</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'time'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">></span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">Date</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">now</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">-</span><span class="token plain"> oneDay</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">hideLoadingSpinner</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="resync">reSync()<a href="#resync" class="hash-link" aria-label="Direct link to reSync()" title="Direct link to reSync()"></a></h3>
<p>Triggers a <code>RESYNC</code> cycle where the replication goes into <a href="#checkpoint-iteration">checkpoint iteration</a> until the client is in sync with the backend. Used in unit tests or when no proper <code>pull.stream$</code> can be implemented so that the client only knows that something has been changed but not what.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">reSync</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<p>If your backend is not capable of sending events to the client at all, you could run <code>reSync()</code> in an interval so that the client will automatically fetch server changes after some time at least.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token comment" style="color:rgb(98, 114, 164)">// trigger RESYNC each 10 seconds.</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token function" style="color:rgb(80, 250, 123)">setInterval</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token plain"> </span><span class="token operator">=></span><span class="token plain"> myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">reSync</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"> </span><span class="token number">10</span><span class="token plain"> </span><span class="token operator">*</span><span class="token plain"> </span><span class="token number">1000</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="cancel">cancel()<a href="#cancel" class="hash-link" aria-label="Direct link to cancel()" title="Direct link to cancel()"></a></h3>
<p>Cancels the replication. Returns a promise that resolved when everything has been cleaned up.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">cancel</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="pause">pause()<a href="#pause" class="hash-link" aria-label="Direct link to pause()" title="Direct link to pause()"></a></h3>
<p>Pauses a running replication. The replication can later be resumed with <code>RxReplicationState.start()</code>.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">pause</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">start</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">// restart</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="remove">remove()<a href="#remove" class="hash-link" aria-label="Direct link to remove()" title="Direct link to remove()"></a></h3>
<p>Cancels the replication and deletes the metadata of the replication state. This can be used to restart the replication "from scratch". Calling <code>.remove()</code> will only delete the replication metadata, it will NOT delete the documents from the collection of the replication.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> myRxReplicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">remove</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="isstopped">isStopped()<a href="#isstopped" class="hash-link" aria-label="Direct link to isStopped()" title="Direct link to isStopped()"></a></h3>
<p>Returns <code>true</code> if the replication is stopped. This can be if a non-live replication is finished or a replication got canceled.</p>
<div class="language-js codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-js codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">replicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token method function property-access" style="color:rgb(80, 250, 123)">isStopped</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">// true/false</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="ispaused">isPaused()<a href="#ispaused" class="hash-link" aria-label="Direct link to isPaused()" title="Direct link to isPaused()"></a></h3>
<p>Returns <code>true</code> if the replication is paused.</p>
<div class="language-js codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-js codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token plain">replicationState</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token method function property-access" style="color:rgb(80, 250, 123)">isPaused</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">// true/false</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="setting-a-custom-initialcheckpoint">Setting a custom initialCheckpoint<a href="#setting-a-custom-initialcheckpoint" class="hash-link" aria-label="Direct link to Setting a custom initialCheckpoint" title="Direct link to Setting a custom initialCheckpoint"></a></h3>
<p>By default, the push replication will start from the beginning of time and push all documents from there to the remote.
By setting a custom <code>push.initialCheckpoint</code>, you can tell the replication to only push writes that are newer than the given checkpoint.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token comment" style="color:rgb(98, 114, 164)">// store the latest checkpoint of a collection</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">let</span><span class="token plain"> lastLocalCheckpoint</span><span class="token operator">:</span><span class="token plain"> </span><span class="token builtin" style="color:rgb(189, 147, 249)">any</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain">myCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token plain">checkpoint$</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">subscribe</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token plain">checkpoint </span><span class="token operator">=></span><span class="token plain"> lastLocalCheckpoint </span><span class="token operator">=</span><span class="token plain"> checkpoint</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// start the replication but only push documents that are newer than the lastLocalCheckpoint</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> replicationState </span><span class="token operator">=</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">replicateRxCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> collection</span><span class="token operator">:</span><span class="token plain"> myCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> replicationIdentifier</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'my-custom-replication-with-init-checkpoint'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">/* ... */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> push</span><span class="token operator">:</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> handler</span><span class="token operator">:</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">/* ... */</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> initialCheckpoint</span><span class="token operator">:</span><span class="token plain"> lastLocalCheckpoint</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<p>The same can be done for the other direction by setting a <code>pull.initialCheckpoint</code>. Notice that here we need the remote checkpoint from the backend instead of the one from the RxDB storage.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token comment" style="color:rgb(98, 114, 164)">// get the last pull checkpoint from the server</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> lastRemoteCheckpoint </span><span class="token operator">=</span><span class="token plain"> </span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">await</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">fetch</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token string" style="color:rgb(255, 121, 198)">'http://example.com/pull-checkpoint'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">.</span><span class="token function" style="color:rgb(80, 250, 123)">json</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain" style="display:inline-block"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token comment" style="color:rgb(98, 114, 164)">// start the replication but only pull documents that are newer than the lastRemoteCheckpoint</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> replicationState </span><span class="token operator">=</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">replicateRxCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> collection</span><span class="token operator">:</span><span class="token plain"> myCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> replicationIdentifier</span><span class="token operator">:</span><span class="token plain"> </span><span class="token string" style="color:rgb(255, 121, 198)">'my-custom-replication-with-init-checkpoint'</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">/* ... */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> pull</span><span class="token operator">:</span><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> handler</span><span class="token operator">:</span><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">/* ... */</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> initialCheckpoint</span><span class="token operator">:</span><span class="token plain"> lastRemoteCheckpoint</span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="toggleondocumentvisible">toggleOnDocumentVisible<a href="#toggleondocumentvisible" class="hash-link" aria-label="Direct link to toggleOnDocumentVisible" title="Direct link to toggleOnDocumentVisible"></a></h3>
<p><code>(experimental)</code></p>
<p>Set this to true to ensure the replication also runs if the tab is currently <code>visbile</code>. This fixes problem in browsers where the replicating leader-elected tab becomes stale or hibernated by the browser to save battery life. If the tab is losing visibility, the replication will be paused automatically and then restarted if either the tab becomes leader or the tab becomes visible again.</p>
<div class="language-ts codeBlockContainer_Ckt0 theme-code-block" style="--prism-color:#F8F8F2;--prism-background-color:#282A36"><div class="codeBlockContent_biex"><pre tabindex="0" class="prism-code language-ts codeBlock_bY9V thin-scrollbar" style="color:#F8F8F2;background-color:#282A36"><code class="codeBlockLines_e6Vv"><span class="token-line" style="color:#F8F8F2"><span class="token keyword" style="color:rgb(189, 147, 249);font-style:italic">const</span><span class="token plain"> replicationState </span><span class="token operator">=</span><span class="token plain"> </span><span class="token function" style="color:rgb(80, 250, 123)">replicateRxCollection</span><span class="token punctuation" style="color:rgb(248, 248, 242)">(</span><span class="token punctuation" style="color:rgb(248, 248, 242)">{</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> toggleOnDocumentVisible</span><span class="token operator">:</span><span class="token plain"> </span><span class="token boolean">true</span><span class="token punctuation" style="color:rgb(248, 248, 242)">,</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"> </span><span class="token comment" style="color:rgb(98, 114, 164)">/* ... */</span><span class="token plain"></span><br></span><span class="token-line" style="color:#F8F8F2"><span class="token plain"></span><span class="token punctuation" style="color:rgb(248, 248, 242)">}</span><span class="token punctuation" style="color:rgb(248, 248, 242)">)</span><span class="token punctuation" style="color:rgb(248, 248, 242)">;</span><br></span></code></pre><div class="buttonGroup__atx"><button type="button" aria-label="Copy code to clipboard" title="Copy" class="clean-btn"><span class="copyButtonIcons_eSgA" aria-hidden="true"><svg viewBox="0 0 24 24" class="copyButtonIcon_y97N"><path fill="currentColor" d="M19,21H8V7H19M19,5H8A2,2 0 0,0 6,7V21A2,2 0 0,0 8,23H19A2,2 0 0,0 21,21V7A2,2 0 0,0 19,5M16,1H4A2,2 0 0,0 2,3V17H4V3H16V1Z"></path></svg><svg viewBox="0 0 24 24" class="copyButtonSuccessIcon_LjdS"><path fill="currentColor" d="M21,7L9,19L3.5,13.5L4.91,12.09L9,16.17L19.59,5.59L21,7Z"></path></svg></span></button></div></div></div>
<h3 class="anchor anchorWithStickyNavbar_LWe7" id="attachment-replication-beta">Attachment replication (beta)<a href="#attachment-replication-beta" class="hash-link" aria-label="Direct link to Attachment replication (beta)" title="Direct link to Attachment replication (beta)"></a></h3>
<p>Attachment replication is supported in the RxDB replication protocol itself. However not all replication plugins support it.
If you start the replication with a collection which has <a href="/rx-attachment.html">enabled RxAttachments</a> attachments data will be added to all push- and write data.</p>
<p>The pushed documents will contain an <code>_attachments</code> object which contains:</p>
<ul>
<li>The attachment meta data (id, length, digest) of all non-attachments</li>
<li>The full attachment data of all attachments that have been updated/added from the client.</li>
<li>Deleted attachments are spared out in the pushed document.</li>
</ul>
<p>With this data, the backend can decide onto which attachments must be deleted, added or overwritten.</p>
<p>Accordingly, the pulled document must contain the same data, if the backend has a new document state with updated attachments.</p>
<h2 class="anchor anchorWithStickyNavbar_LWe7" id="faq">FAQ<a href="#faq" class="hash-link" aria-label="Direct link to FAQ" title="Direct link to FAQ"></a></h2>
<details class="details_lb9f alert alert--info details_b_Ee" data-collapsed="true"><summary>I have infinite loops in my replication, how to debug?</summary><div><div class="collapsibleContent_i85q"><div><p>When you have infinite loops in your replication or random re-runs of http requests after some time, the reason is likely that your pull-handler
is crashing. The debug this, add a log to the error$ handler to debug it. <code>myRxReplicationState.error$.subscribe(err => console.log('error$', err))</code>.</p></div></div></div></details></div></article><nav class="pagination-nav docusaurus-mt-lg" aria-label="Docs pages"><a class="pagination-nav__link pagination-nav__link--prev" href="/electron.html"><div class="pagination-nav__sublabel">Previous</div><div class="pagination-nav__label">Electron</div></a><a class="pagination-nav__link pagination-nav__link--next" href="/replication-http.html"><div class="pagination-nav__sublabel">Next</div><div class="pagination-nav__label">HTTP Replication</div></a></nav></div></div><div class="col col--3"><div class="tableOfContents_bqdL thin-scrollbar theme-doc-toc-desktop"><ul class="table-of-contents table-of-contents__left-border"><li><a href="#design-decisions" class="table-of-contents__link toc-highlight">Design Decisions</a></li><li><a href="#replication-protocol-on-the-document-level" class="table-of-contents__link toc-highlight">Replication protocol on the document level</a></li><li><a href="#replication-protocol-on-the-transfer-level" class="table-of-contents__link toc-highlight">Replication protocol on the transfer level</a><ul><li><a href="#checkpoint-iteration" class="table-of-contents__link toc-highlight">Checkpoint iteration</a></li><li><a href="#event-observation" class="table-of-contents__link toc-highlight">Event observation</a></li></ul></li><li><a href="#data-layout-on-the-server" class="table-of-contents__link toc-highlight">Data layout on the server</a></li><li><a href="#conflict-handling" class="table-of-contents__link toc-highlight">Conflict handling</a></li><li><a href="#replicaterxcollection" class="table-of-contents__link toc-highlight">replicateRxCollection()</a></li><li><a href="#multi-tab-support" class="table-of-contents__link toc-highlight">Multi Tab support</a></li><li><a href="#error-handling" class="table-of-contents__link toc-highlight">Error handling</a></li><li><a href="#security" class="table-of-contents__link toc-highlight">Security</a></li><li><a href="#rxreplicationstate" class="table-of-contents__link toc-highlight">RxReplicationState</a><ul><li><a href="#observable" class="table-of-contents__link toc-highlight">Observable</a></li><li><a href="#awaitinitialreplication" class="table-of-contents__link toc-highlight">awaitInitialReplication()</a></li><li><a href="#awaitinsync" class="table-of-contents__link toc-highlight">awaitInSync()</a></li><li><a href="#resync" class="table-of-contents__link toc-highlight">reSync()</a></li><li><a href="#cancel" class="table-of-contents__link toc-highlight">cancel()</a></li><li><a href="#pause" class="table-of-contents__link toc-highlight">pause()</a></li><li><a href="#remove" class="table-of-contents__link toc-highlight">remove()</a></li><li><a href="#isstopped" class="table-of-contents__link toc-highlight">isStopped()</a></li><li><a href="#ispaused" class="table-of-contents__link toc-highlight">isPaused()</a></li><li><a href="#setting-a-custom-initialcheckpoint" class="table-of-contents__link toc-highlight">Setting a custom initialCheckpoint</a></li><li><a href="#toggleondocumentvisible" class="table-of-contents__link toc-highlight">toggleOnDocumentVisible</a></li><li><a href="#attachment-replication-beta" class="table-of-contents__link toc-highlight">Attachment replication (beta)</a></li></ul></li><li><a href="#faq" class="table-of-contents__link toc-highlight">FAQ</a></li></ul></div></div></div></div></main></div></div></div><div class="block footer"><div class="footer-block"><div class="footer-links"><span><a variant="text" href="/" class="footer-logo-button"><img src="/files/logo/logo.svg" alt="RxDB" loading="lazy"><div>RxDB</div></a><div class="footer-community-links"><a variant="text" href="/chat/" target="_blank"><img src="/img/community-links/discord-logo.svg" alt="RxDB Discord" loading="lazy"></a><a variant="text" 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