docs/quickstart/index.html

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<!-- [START docs_quickstart] -->
<!DOCTYPE html>
<html>
  <head>
    <title>Google Docs API Quickstart</title>
    <meta charset="utf-8" />
  </head>
  <body>
    <p>Google Docs API Quickstart</p>

    <!--Add buttons to initiate auth sequence and sign out-->
    <button id="authorize_button" onclick="handleAuthClick()">Authorize</button>
    <button id="signout_button" onclick="handleSignoutClick()">Sign Out</button>

    <pre id="content" style="white-space: pre-wrap;"></pre>

    <script type="text/javascript">
      /* exported gapiLoaded */
      /* exported gisLoaded */
      /* exported handleAuthClick */
      /* exported handleSignoutClick */

      // TODO(developer): Set to client ID and API key from the Developer Console
      const CLIENT_ID = '<YOUR_CLIENT_ID>';
      const API_KEY = '<YOUR_API_KEY>';

      // Discovery doc URL for APIs used by the quickstart
      const DISCOVERY_DOC = 'https://docs.googleapis.com/$discovery/rest?version=v1';

      // Authorization scopes required by the API; multiple scopes can be
      // included, separated by spaces.
      const SCOPES = 'https://www.googleapis.com/auth/documents.readonly';

      let tokenClient;
      let gapiInited = false;
      let gisInited = false;

      document.getElementById('authorize_button').style.visibility = 'hidden';
      document.getElementById('signout_button').style.visibility = 'hidden';

      /**
       * Callback after api.js is loaded.
       */
      function gapiLoaded() {
        gapi.load('client', initializeGapiClient);
      }

      /**
       * Callback after the API client is loaded. Loads the
       * discovery doc to initialize the API.
       */
      async function initializeGapiClient() {
        await gapi.client.init({
          apiKey: API_KEY,
          discoveryDocs: [DISCOVERY_DOC],
        });
        gapiInited = true;
        maybeEnableButtons();
      }

      /**
       * Callback after Google Identity Services are loaded.
       */
      function gisLoaded() {
        tokenClient = google.accounts.oauth2.initTokenClient({
          client_id: CLIENT_ID,
          scope: SCOPES,
          callback: '', // defined later
        });
        gisInited = true;
        maybeEnableButtons();
      }

      /**
       * Enables user interaction after all libraries are loaded.
       */
      function maybeEnableButtons() {
        if (gapiInited && gisInited) {
          document.getElementById('authorize_button').style.visibility = 'visible';
        }
      }

      /**
       *  Sign in the user upon button click.
       */
      function handleAuthClick() {
        tokenClient.callback = async (resp) => {
          if (resp.error !== undefined) {
            throw (resp);
          }
          document.getElementById('signout_button').style.visibility = 'visible';
          document.getElementById('authorize_button').innerText = 'Refresh';
          await printDocTitle();
        };

        if (gapi.client.getToken() === null) {
          // Prompt the user to select a Google Account and ask for consent to share their data
          // when establishing a new session.
          tokenClient.requestAccessToken({prompt: 'consent'});
        } else {
          // Skip display of account chooser and consent dialog for an existing session.
          tokenClient.requestAccessToken({prompt: ''});
        }
      }

      /**
       *  Sign out the user upon button click.
       */
      function handleSignoutClick() {
        const token = gapi.client.getToken();
        if (token !== null) {
          google.accounts.oauth2.revoke(token.access_token);
          gapi.client.setToken('');
          document.getElementById('content').innerText = '';
          document.getElementById('authorize_button').innerText = 'Authorize';
          document.getElementById('signout_button').style.visibility = 'hidden';
        }
      }

      /**
       * Prints the title of a sample doc:
       * https://docs.google.com/document/d/195j9eDD3ccgjQRttHhJPymLJUCOUjs-jmwTrekvdjFE/edit
       */
      async function printDocTitle() {
        try {
          const response = await gapi.client.docs.documents.get({
            documentId: '195j9eDD3ccgjQRttHhJPymLJUCOUjs-jmwTrekvdjFE',
          });
          const doc = response.result;
          const output = `Document ${doc.title} successfully found.\n`;
          document.getElementById('content').innerText = output;
        } catch (err) {
          document.getElementById('content').innerText = err.message;
          return;
        }
      }
    </script>
    <script async defer src="https://apis.google.com/js/api.js" onload="gapiLoaded()"></script>
    <script async defer src="https://accounts.google.com/gsi/client" onload="gisLoaded()"></script>
  </body>
</html>
<!-- [END docs_quickstart] -->