Step 1: Get permission from user with an google prompt
Step 2: After user give response Google redirects you to specificed redirect_url(http://localhost:8080/) wit
h an authorization code in it
Step 3: Handle the OAuth2.0 server response i.e., get the authorization code present in redirect_url
Step 4: Exchange this Authorization code with access token from Google API
Step 5: Use this access token and client_secret which we got at the time of creating project in Google develope
rs console. This will be done by rocket.chat server, for that we need to send method to the server.