gdrive-utils/lib/generateToken.js

Utility functions(Upload/Download files,check the files available in the drive) for google drive api.

var fs = require('fs');

var readline = require('readline');
var googleAuth = require('google-auth-library');

var SCOPES = [
    'https://www.googleapis.com/auth/drive',
    'https://www.googleapis.com/auth/drive.file'
];
var TOKEN_PATH = 'auth_token.json';
/**
 * 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) {
    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);
        } else {
            oauth2Client.credentials = JSON.parse(token);
            console.log(JSON.parse(token));
        }
    });
}

/**
 * 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);
        });
    });
}

/**
 * Store token to disk be used in later program executions.
 *
 * @param {Object} token The token to store to disk.
 */
function storeToken(token) {
    fs.writeFile(TOKEN_PATH, JSON.stringify(token));
    console.log('Token stored to ' + TOKEN_PATH);
}


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
    // Drive API.
    authorize(JSON.parse(content));
});