Node.jsでGoogle Slides内のテキストを取得してみる

const fs = require('fs');
const readline = require('readline');
const {google} = require('googleapis');

//変更箇所: プレゼンテーションID - 試すときは自分のスライドでもやってみましょう
const presentationId = `1ziVnaFocZ_YF_cuXyXF5PUKGoE62eX-XlnOEslPkKUc`;

// If modifying these scopes, delete token.json.
const SCOPES = ['https://www.googleapis.com/auth/presentations.readonly'];
// The file token.json stores the user's access and refresh tokens, and is
// created automatically when the authorization flow completes for the first
// time.
const TOKEN_PATH = 'token.json';

// Load client secrets from a local file.
fs.readFile('credentials.json', (err, content) => {
  if (err) return console.log('Error loading client secret file:', err);
  // Authorize a client with credentials, then call the Google Slides API.
  authorize(JSON.parse(content), listSlides);
});

/**
 * Create an OAuth2 client with the given credentials, and then execute the
 * given callback function.
 * @param {Object} credentials The authorization client credentials.
 * @param {function} callback The callback to call with the authorized client.
 */
function authorize(credentials, callback) {
  const {client_secret, client_id, redirect_uris} = credentials.installed;
  const oAuth2Client = new google.auth.OAuth2(
      client_id, client_secret, redirect_uris[0]);

  // Check if we have previously stored a token.
  fs.readFile(TOKEN_PATH, (err, token) => {
    if (err) return getNewToken(oAuth2Client, callback);
    oAuth2Client.setCredentials(JSON.parse(token));
    callback(oAuth2Client);
  });
}

/**
 * Get and store new token after prompting for user authorization, and then
 * execute the given callback with the authorized OAuth2 client.
 * @param {google.auth.OAuth2} oAuth2Client The OAuth2 client to get token for.
 * @param {getEventsCallback} callback The callback for the authorized client.
 */
function getNewToken(oAuth2Client, callback) {
  const authUrl = oAuth2Client.generateAuthUrl({
    access_type: 'offline',
    scope: SCOPES,
  });
  console.log('Authorize this app by visiting this url:', authUrl);
  const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
  });
  rl.question('Enter the code from that page here: ', (code) => {
    rl.close();
    oAuth2Client.getToken(code, (err, token) => {
      if (err) return console.error('Error retrieving access token', err);
      oAuth2Client.setCredentials(token);
      // Store the token to disk for later program executions
      fs.writeFile(TOKEN_PATH, JSON.stringify(token), (err) => {
        if (err) return console.error(err);
        console.log('Token stored to', TOKEN_PATH);
      });
      callback(oAuth2Client);
    });
  });
}

/**
 * Prints the number of slides and elements in a sample presentation:
 * https://docs.google.com/presentation/d/1EAYk18WDjIG-zp_0vLm3CsfQh_i8eXc67Jo2O9C6Vuc/edit
 * @param {google.auth.OAuth2} auth The authenticated Google OAuth client.
 * 
 */
function listSlides(auth) {
  const slides = google.slides({version: 'v1', auth});
  slides.presentations.get({
    presentationId: presentationId,
  }, (err, res) => {
    if (err) return console.log('The API returned an error: ' + err);

    /* 変更箇所: スライド中のテキストを抽出するテスト */
    const firstPage = res.data.slides[0]; //1スライド目
    const firstBox = firstPage.pageElements[0]; //最初の要素
    console.log(firstBox.shape.text.textElements[1].textRun.content); //中身のテキスト確認
  });
}

res.data.slides[0].pageElements[0].shape.text.textElements[1].textRun.content

$ node app.js 
Node.jsてすと