From 954f7e0cc35b03b03adca7557128e083df76a9c0 Mon Sep 17 00:00:00 2001
From: Andy Diamondstein <adiamondstein@google.com>
Date: Tue, 25 Apr 2017 12:02:34 -0400
Subject: [PATCH] Add file for coming-soon node.js quickstart guide.

---
 javascript/nodejs-quickstart.js | 124 ++++++++++++++++++++++++++++++++
 1 file changed, 124 insertions(+)
 create mode 100644 javascript/nodejs-quickstart.js

diff --git a/javascript/nodejs-quickstart.js b/javascript/nodejs-quickstart.js
new file mode 100644
index 00000000..4e9f26a4
--- /dev/null
+++ b/javascript/nodejs-quickstart.js
@@ -0,0 +1,124 @@
+var fs = require('fs');
+var readline = require('readline');
+var google = require('googleapis');
+var googleAuth = require('google-auth-library');
+
+// If modifying these scopes, delete your previously saved credentials
+// at ~/.credentials/youtube-nodejs-quickstart.json
+var SCOPES = ['https://www.googleapis.com/auth/youtube.readonly'];
+var TOKEN_DIR = (process.env.HOME || process.env.HOMEPATH ||
+    process.env.USERPROFILE) + '/.credentials/';
+var TOKEN_PATH = TOKEN_DIR + 'youtube-nodejs-quickstart.json';
+
+// Load client secrets from a local file.
+fs.readFile('client_secret.json', function processClientSecrets(err, content) {
+  if (err) {
+    console.log('Error loading client secret file: ' + err);
+    return;
+  }
+  // Authorize a client with the loaded credentials, then call the YouTube API.
+  authorize(JSON.parse(content), getChannel);
+});
+
+/**
+ * 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) {
+  var clientSecret = credentials.installed.client_secret;
+  var clientId = credentials.installed.client_id;
+  var redirectUrl = credentials.installed.redirect_uris[0];
+  var auth = new googleAuth();
+  var oauth2Client = new auth.OAuth2(clientId, clientSecret, redirectUrl);
+
+  // Check if we have previously stored a token.
+  fs.readFile(TOKEN_PATH, function(err, token) {
+    if (err) {
+      getNewToken(oauth2Client, callback);
+    } else {
+      oauth2Client.credentials = 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 to call with the authorized
+ *     client.
+ */
+function getNewToken(oauth2Client, callback) {
+  var authUrl = oauth2Client.generateAuthUrl({
+    access_type: 'offline',
+    scope: SCOPES
+  });
+  console.log('Authorize this app by visiting this url: ', authUrl);
+  var rl = readline.createInterface({
+    input: process.stdin,
+    output: process.stdout
+  });
+  rl.question('Enter the code from that page here: ', function(code) {
+    rl.close();
+    oauth2Client.getToken(code, function(err, token) {
+      if (err) {
+        console.log('Error while trying to retrieve access token', err);
+        return;
+      }
+      oauth2Client.credentials = token;
+      storeToken(token);
+      callback(oauth2Client);
+    });
+  });
+}
+
+/**
+ * Store token to disk be used in later program executions.
+ *
+ * @param {Object} token The token to store to disk.
+ */
+function storeToken(token) {
+  try {
+    fs.mkdirSync(TOKEN_DIR);
+  } catch (err) {
+    if (err.code != 'EEXIST') {
+      throw err;
+    }
+  }
+  fs.writeFile(TOKEN_PATH, JSON.stringify(token));
+  console.log('Token stored to ' + TOKEN_PATH);
+}
+
+/**
+ * Lists the names and IDs of up to 10 files.
+ *
+ * @param {google.auth.OAuth2} auth An authorized OAuth2 client.
+ */
+function getChannel(auth) {
+  var service = google.youtube('v3');
+  service.channels.list({
+    auth: auth,
+    part: 'snippet,contentDetails,statistics',
+    forUsername: 'GoogleDevelopers'
+  }, function(err, response) {
+    if (err) {
+      console.log('The API returned an error: ' + err);
+      return;
+    }
+    var channels = response.items;
+    if (channels.length == 0) {
+      console.log('No channel found.');
+    } else {
+      console.log('This channel\'s ID is %s. Its title is \'%s\', and ' +
+                  'it has %s views.',
+                  channels[0].id,
+                  channels[0].snippet.title,
+                  channels[0].statistics.viewCount);
+    }
+  });
+}