first pass, captions only

Author: shiffman

.gitignore

@@ -0,0 +1,5 @@
+token.json
+credentials.json
+node_modules
+.DS_Store
+captions

index.js

@@ -0,0 +1,135 @@
+import { google } from 'googleapis';
+import fs from 'fs';
+import express from 'express';
+
+const SCOPES = ['https://www.googleapis.com/auth/youtube.force-ssl'];
+const TOKEN_PATH = 'token.json';
+const PORT = 3000;
+
+main();
+
+async function main() {
+  const authClient = await authenticateYouTube();
+  const youtube = google.youtube({ version: 'v3', auth: authClient });
+  const channel = await youtube.channels.list({
+    part: 'contentDetails',
+    mine: true,
+  });
+
+  // const channelId = channel.data.items[0].id;
+  const uploadsId =
+    channel.data.items[0].contentDetails.relatedPlaylists.uploads;
+
+  let nextPage;
+  do {
+    const videos = await youtube.playlistItems.list({
+      part: 'snippet',
+      playlistId: uploadsId,
+      maxResults: 50,
+      pageToken: nextPage,
+    });
+
+    for (let item of videos.data.items) {
+      const id = item.snippet.resourceId.videoId;
+      const title = item.snippet.title;
+      await getCaptions(id, title);
+    }
+
+    nextPage = videos.data.nextPageToken;
+  } while (nextPage);
+
+  async function getCaptions(id, title) {
+    const captionsList = await youtube.captions.list({
+      part: 'snippet',
+      videoId: id,
+    });
+    const captions = captionsList.data.items;
+    if (captions.length === 0) {
+      console.log(`No captions available ${videoId}`);
+      return;
+    }
+    // Just get first captions for now?
+    const captionId = captions[0].id;
+    const download = await youtube.captions.download({
+      id: captionId,
+      tfmt: 'srt',
+    });
+
+    const dir = 'captions';
+    if (!fs.existsSync(dir)) fs.mkdirSync(dir);
+    const fileTitle = title.replace(/[^a-z0-9]+/gi, '_').toLowerCase();
+    const filename = `${dir}/${fileTitle}_${id}.srt`;
+
+    const arrayBuffer = await download.data.arrayBuffer();
+    const buffer = Buffer.from(arrayBuffer);
+    fs.writeFileSync(filename, buffer);
+    console.log(`Captions saved to ${filename}`);
+  }
+}
+
+// First:
+// Go to the Google Developers Console.
+// Create a new project.
+// Enable the YouTube Data API v3 for that project.
+// Go to the "Credentials" tab and click "Create Credentials". Choose "OAuth 2.0 Client ID".
+// For the application type, choose "Desktop app" (for testing purposes).
+// Download the credentials JSON file.
+
+async function authenticateYouTube() {
+  return new Promise((resolve, reject) => {
+    let oAuth2Client = createOAuthClient();
+
+    const app = express();
+
+    app.get('/', async (req, res) => {
+      if (req.query.code) {
+        const { tokens } = await oAuth2Client.getToken(req.query.code);
+        fs.writeFileSync(TOKEN_PATH, JSON.stringify(tokens));
+        oAuth2Client.setCredentials(tokens);
+        res.send('Token stored to token.json');
+        resolve(oAuth2Client);
+      } else if (!oAuth2Client.credentials.access_token) {
+        const authUrl = oAuth2Client.generateAuthUrl({
+          access_type: 'offline',
+          scope: SCOPES,
+        });
+        res.send(
+          `<a href="${authUrl}">Authorize this app by visiting this link</a>`
+        );
+      } else {
+        res.send('Already authenticated with YouTube.');
+        resolve(oAuth2Client);
+      }
+    });
+
+    app.listen(PORT, () => {
+      if (!oAuth2Client.credentials.access_token) {
+        console.log(`Authorize app at: http://localhost:${PORT}`);
+      } else {
+        console.log(
+          `App is already authorized. Listening at: http://localhost:${PORT}`
+        );
+        resolve(oAuth2Client);
+      }
+    });
+  });
+}
+
+function createOAuthClient() {
+  const content = fs.readFileSync('credentials.json', 'utf-8');
+  const credentials = JSON.parse(content);
+  const { client_secret, client_id, redirect_uris } = credentials.installed;
+
+  const client = new google.auth.OAuth2(
+    client_id,
+    client_secret,
+    redirect_uris[0]
+  );
+  try {
+    const token = fs.readFileSync(TOKEN_PATH, 'utf-8');
+    client.setCredentials(JSON.parse(token));
+  } catch (error) {
+    console.log('No token found.');
+  }
+  return client;
+}