CODEWITHSUNDEEP
javascriptnode.jsgoogle-apigmailgoogle-apis-explorer
dthareja
dthareja

Reputation: 146

Failed sending mail with googleapis' service account and JWT auth in nodejs

I'm trying to send an email using a service account and JWT authentication and keep getting and error with a very unhelpful message: { code: 500, message: null }

This code snippet is from the following StackOverflow link: Failed sending mail through google api in nodejs

It seems like the solution there was to change the key in the parameters to resource instead of message but it's not working for me. This is strange because in the JS example in the docs (https://developers.google.com/gmail/api/v1/reference/users/messages/send) it claims the key is still message

I'm authenticating with

var jwtClient = new google.auth.JWT(config.SERVICE_EMAIL, config.SERVICE_KEY_PATH, null, config.ALLOWED_SCOPES);

then sending an email with

jwtClient.authorize(function(err, res) {
  if (err) return console.log('err', err);

  var email_lines = [];

  email_lines.push("From: \"Some Name Here\" <[email protected]>");
  email_lines.push("To: [email protected]");
  email_lines.push('Content-type: text/html;charset=iso-8859-1');
  email_lines.push('MIME-Version: 1.0');
  email_lines.push("Subject: New future subject here");
  email_lines.push("");
  email_lines.push("And the body text goes here");
  email_lines.push("<b>And the bold text goes here</b>");

  var email = email_lines.join("\r\n").trim();

  var base64EncodedEmailSafe = new Buffer(email).toString('base64').replace(/\+/g, '-').replace(/\//g, '_');

  var params = {
    auth: jwtClient,
    userId: "[email protected]",
    resource: {
      raw: base64EncodedEmailSafe
    }
  };

  gmail.users.messages.send(params, function(err, res) {
    if (err) console.log('error sending mail', err);
    else console.log('great success', res);
  });
}

The comments in the library seem to say that resource is the correct property as well (https://github.com/google/google-api-nodejs-client/blob/master/apis/gmail/v1.js)

The comments in the library seem to say that resource is the correct property as well What am I missing?

Upvotes: 2

Views: 787

Answers (1)

dthareja
dthareja

Reputation: 146

According to @ryanseys on github

You cannot authorize Gmail API requests with JWT, you must use OAuth 2.0 because it needs to be auth'd to a specific user. Or else you'd be able to do some really shady things like send messages impersonating someone else. The Google APIs Explorer is authenticated with OAuth 2.0 that's why it works. See https://developers.google.com/gmail/api/auth/about-auth for more information.

As you can see in Failed sending mail through google api in nodejs, auth: OAuth2Client, they are using the OAuth2 client to authenticate. There is currently no way for you to send messages using the GMail API without authenticating as a specific GMail user. Service accounts do not have access to GMail the same way that regular users do.

Hopefully this helps someone else out there trying to use a service account to send mail!

Upvotes: 1

Related Questions