google-api-methods.js

Meteor.methods({
  // Obtain a new access token using the refresh token
  exchangeRefreshToken: function(userId) {
    this.unblock();
    
    if (this.connection) {  //when called from client
      if (this.userId) {
        userId = this.userId;
      } else {
        throw new Meteor.Error(403, "Must be signed in to use Google API.");
      } 
    }
    
    var user;
    if (userId && Meteor.isServer) {
      user = Meteor.users.findOne({_id: userId});
    } else {
      user = Meteor.user();
    }

    var config = Accounts.loginServiceConfiguration.findOne({service: "google"});
    if (! config)
      throw new Meteor.Error(500, "Google service not configured.");

    if (! user.services || ! user.services.google || ! user.services.google.refreshToken)
      throw new Meteor.Error(500, "Refresh token not found.");
    
    try {
      var result = HTTP.call("POST",
        "https://accounts.google.com/o/oauth2/token",
        {
          params: {
            'client_id': config.clientId,
            'client_secret': config.secret,
            'refresh_token': user.services.google.refreshToken,
            'grant_type': 'refresh_token'
          }
      });
    } catch (e) {
      var code = e.response ? e.response.statusCode : 500;
      throw new Meteor.Error(code, 'Unable to exchange google refresh token.', e.response)
    }
    
    if (result.statusCode === 200) {
      // console.log('success');
      // console.log(EJSON.stringify(result.data));

      Meteor.users.update(user._id, { 
        '$set': { 
          'services.google.accessToken': result.data.access_token,
          'services.google.expiresAt': (+new Date) + (1000 * result.data.expires_in),
        }
      });

      return result.data;
    } else {
      throw new Meteor.Error(result.statusCode, 'Unable to exchange google refresh token.', result);
    }
  }
});