Not receiving Google OAuth refresh token

The refresh_token is only provided on the first authorization from the user. Subsequent authorizations, such as the kind you make while testing an OAuth2 integration, will not return the refresh_token again. :)

1. Go to the page showing Apps with access to your account: https://myaccount.google.com/u/0/permissions.
2. Under the Third-party apps menu, choose your app.
3. Click Remove access and then click Ok to confirm
4. The next OAuth2 request you make will return a refresh_token (providing that it also includes the 'access_type=offline' query parameter.

Alternatively, you can add the query parameters prompt=consent&access_type=offline to the OAuth redirect (see Google's OAuth 2.0 for Web Server Applications page).

This will prompt the user to authorize the application again and will always return a refresh_token.

In order to get the refresh token you have to add both approval_prompt=force and access_type="offline" If you are using the java client provided by Google it will look like this:

GoogleAuthorizationCodeFlow flow = new GoogleAuthorizationCodeFlow.Builder(
            HTTP_TRANSPORT, JSON_FACTORY, getClientSecrets(), scopes)
            .build();

AuthorizationCodeRequestUrl authorizationUrl =
            flow.newAuthorizationUrl().setRedirectUri(callBackUrl)
                    .setApprovalPrompt("force")
                    .setAccessType("offline");