Gmail API with PHP

I'm using the Gmail API for reads emails and just add/remove labels.

I authenticated correctly, I get my access token with 3600 seconds of life.

And here starts the problems... When I try to Refresh Token, I got a null, so I can't refresh it.

Some code:

 $this->client = new Client();
 $this->client->setApplicationName('App');
 $this->client->setClientId('xxxxxxx');
 $this->client->setClientSecret('xxxxxxx');
 $this->client->setRedirectUri('xxxxxxx/oauth/gmail/callback');
 $this->client->setScopes([GoogleGmail::GMAIL_READONLY, GoogleGmail::GMAIL_MODIFY]);
 $this->client->setPrompt('select_account consent');
 $this->client->setAccessType('offline');

In the callback I do:

$this->client->fetchAccessTokenWithAuthCode($code);

Output:

{
"access_token":"xxxxxxxxxx",
"expires_in":3599,
"scope":"https:\/\/www.googleapis.com\/auth\/gmail.readonly https:\/\/www.googleapis.com\/auth\/gmail.modify",
"token_type":"Bearer",
"created":7374384324 
}

I saved the Access Token, Expired time, and all data really. But I don't get the refresh token.

I try with:

$this->client->getRefreshToken(); // null

And If I do

$this->client->isAccessTokenExpired()

I always get true, inclusive if I auth 5 seconds ago.

I'm using google/apiclient v2.15.0, PHP 8.1

Thanks

You only get a refresh token with the first time the user has authenticated your application. You need to store that in your application along with the users name so that you can then send that when you would like to request a new access token.

A refresh of an access token in a web app will not return a new refresh token. Requesting authorization again will also not result in a new refresh token.