Cannot refresh token in Google API - php

Question

The goal
I need to fetch data from Google Analytics after my users have logged out. Basically they will go to my site, authorize my app to access their GA data and at midnight I fetch the data and process it in my service.
My current flow
After reading many any posts and questions here is what I have come up:
The front end part looks like somewhat this:
<script src="https://apis.google.com/js/client:platform.js?onload=start" async defer></script>
<script>
function start() {
gapi.load('auth2', function() {
auth2 = gapi.auth2.init({
client_id: '{{CLIENT_ID}}.apps.googleusercontent.com',
scope: 'https://www.googleapis.com/auth/analytics',
access_type: 'offline'
});
});
}
$('#signinButton').click(function() {
auth2.grantOfflineAccess({
'redirect_uri': 'postmessage'
}).then(signInCallback);
});
function signInCallback(authResult) {
window.console.log('signInCallback: This code must be exchanged by the server, it grants access to request a refresh token: ',authResult, arguments);
if (authResult['code']) {
// Hide the sign-in button now that the user is authorized, for example:
$('#signinButton').attr('style', 'display: none').after('<p>The auth code is: ' + authResult['code'] + '</p>');
$.get('http://mysite.dev/oauth_callback.php?code=' + authResult['code'])
.fail(function(err){console.error(err)})
.done(function(data) {
var message;
if (typeof data.error == 'undefined') {
message = '<div style="border: green solid 1px;">Finished the request and got ' + data + '</div>';
} else {
message = '<div style="border: red solid 1px;">' + data.message + '</div>';
}
$('#signinButton').after(message);
});
} else {
// There was an error.
}
}
</script>
my oauth_callback.php checks the response from google and stores it in the database (please ignore the $.get vs $post bit).
From my tests I see that the auth_code along with the refresh_token and other parts are properly stored in my database.
Now, I manually trigger my midnight script which looks a little like this:
public function get_client() {
// Create and configure a new client object.
$client = new \Google_Client();
$path_to_config = dirname(__FILE__) . DIRECTORY_SEPARATOR . 'my-client-secret.apps.googleusercontent.com.json';
$scopes = array(
'https://www.googleapis.com/auth/analytics'
);
$client->setAuthConfigFile($path_to_config);
$client->setApplicationName("My app");
$client->setAccessType('offline');
return $client;
}
public function fetch_visits() {
foreach ($this->_accounts as $account_id => $auth_json_string) {
$client = $this->get_client();
$ga_code_array = json_decode($auth_json_string, true);
$ga_code_string = $auth_json_string;
$client->setAccessToken($auth_json_string);
var_dump($client);
if ($client->isAccessTokenExpired()) {
$client->setAccessType('offline');
var_dump('Not authed because the access token expired. Requesting another one');
$client->refreshToken($auth_json_string);;
$is_authed_now = $client->isAccessTokenExpired();
var_dump($is_authed_now);
}
die('sadasdsdsa');
}
}
The error
With this code Im getting the infamous:
Google_Auth_Exception: Error refreshing the OAuth2 token, message: '{
"error" : "invalid_grant""
error, which I traced to the OAuth library and basically Google returning an http code 400 (instead of 200) which tells me that the $auth_json_string is not correct, but this is the same string that Google gave me after the user authorized my app, so I dont really know where is the problem.
Please keep in mind that this is a server-to-server app, the user will not be logged in when my service runs, thats why I store the auth json object.
Can you see what Im doing wrong?

Answer 1

For PHP I set the following
$client->setAccessType("refresh_token");
And this resolved my issue. I am using gmail for this but should work for the other Google Services. Remember to save the refresh_token when creating the first access_token request or you will have more issues.
So I now have a function called getClient()
function getClient(){
$googleUser = $this->getUserDetails();
$client = new Google_Client();
$client->setAuthConfigFile('client_secret.json');
$client->setApplicationName("YOUR_APP_NAME");
$data = $googleUser->attributes;
$client->setAccessToken(json_encode($data));
if($client->isAccessTokenExpired()){
$client->addScope(Google_Service_Gmail::MAIL_GOOGLE_COM);
$client->setAccessType("refresh_token");
$client->refreshToken($data['refresh_token']);
$access_token = $client->getAccessToken();
$data1 = json_decode($access_token);
$googleUser->access_token = $data1->access_token;
$googleUser->token_type = $data1->token_type;
$googleUser->expires_in = $data1->expires_in;
$googleUser->created_date = date('Y-m-d h:i:s',$data1->created);
$googleUser->created = $data1->created;
$googleUser->save();
$client->setAccessToken($access_token);
}
return $client;
}