Apply HMR updates via node worker thread #10071
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
When running a node entry point via the Parcel dev server, we execute in a worker thread as of #10055. Previously we still relied on a web socket connection from the node process to the dev server for updates. However, there is an ordering requirement: when the server code is updated, the server needs to handle the HMR update first before the client tries to reload the page or it will receive out of date content or an error.
This updates the node process to use the worker thread's MessagePort to deliver HMR updates directly. The HMR client also replies back to the server after applying an update. Once this occurs, we then deliver the update via the web socket to the browser, which will reload. This way the order is guaranteed to be correct.