google-api-nodejs-client throws invalid_request error when exchanging code with tokens

Question

I've got a simple client app using react-google-login with this settings:

<GoogleLogin
        clientId={config.CLIENT_ID}
        scope={config.SCOPES.join(' ')}
        buttonText="Login With Google"
        onSuccess={response => onSignIn('google', response)}
        onFailure={this.failure.bind(this)}
        accessType="offline"
        responseType="code"
      />

It retrieves the code successfully and sends it to the backend server which is written with NodeJS.

The server-side code looks like this:

const { google } = require('googleapis');
const config = global.config;
const oauth2Client = new google.auth.OAuth2({
  clientId: config.google.CLIENT_ID,
  clientSecret: config.google.CLIENT_SECRET,
});

// code omitted for the sake of simplicity

var authCode = req.body.authCode; // the provided code by google

const { tokens } = await oauth2Client.getToken(authCode);
return tokens;

When I run the code, it throws the error:

{ error: 'invalid_request',
        error_description: 'Missing parameter: redirect_uri' } },
  code: '400' }

and if I add redirectUrl to Developer Console, client app and server-side app, I'll get redirect_uri_mismatch error.

I'm kind of stuck here and couldn't find anything useful on the web.

Any workaround would be appreciated.

Answer 1

Found the solution

Based on one of the replies (surprisingly, not the answer) on this post,

All I needed to do was put postmessage instead of the actual URL in my client react-google-login button and in oauth2Client config on the server.

no need for the redirect_uri on Developer Console at all.

<GoogleLogin
            clientId={config.CLIENT_ID}
            ****redirectUri="postmessage"****
            scope={config.SCOPES.join(' ')}
            buttonText="Login With Google"
            onSuccess={response => onSignIn('google', response)}
            onFailure={this.failure.bind(this)}
            accessType="offline"
            responseType="code"
          />

const oauth2Client = new google.auth.OAuth2({
  clientId: config.google.CLIENT_ID,
  clientSecret: config.google.CLIENT_SECRET,
  ****redirectUri: 'postmessage'****
});

Did solve the issue. 5 hours of working, searching and beating my head to the desk. I wonder why there's no clear documentation on Google Developers website. Or maybe there are and I couldn't find them.