Get refresh token google api

Question

I can't get my refresh token with my code. I can only get my access token, token type etc., I have followed some tutorials like putting access_type=offline on my login URL:

echo "<a href='https://accounts.google.com/o/oauth2/auth?" 
    . "access_type=offline&client_id=123345555.apps.googleusercontent.com& "
    . "scope=https://www.googleapis.com/auth/calendar+https://www.googleapis.com/auth/plus.me&response_type=code& "
    . "redirect_uri=http://www.sample.com/sample.php&state=/profile'>Google</a>";

and my fields in getting the access token:

$fields=array(
    'code'=>  urlencode($authcode),
    'client_id'=> urlencode($clientid),
    'client_secret'=> urlencode($clientsecret),
    'redirect_uri'=> urlencode($redirecturi),
    'grant_type'=> 'authorization_code',
);

but I can't get refresh_token, just the access_token, token_type, id_token and expires_in.

Answer 1

This is complete code in PHP using google official SDK

$client = new Google_Client();
## some need parameter
$client->setApplicationName('your application name');
$client->setClientId('****************');
$client->setClientSecret('************');
$client->setRedirectUri('http://your.website.tld/complete/url2redirect');
$client->setScopes('https://www.googleapis.com/auth/userinfo.email');
## these two lines is important to get refresh token from google api
$client->setAccessType('offline');
$client->setApprovalPrompt('force'); # this line is important when you revoke permission from your app, it will prompt google approval dialogue box forcefully to user to grant offline access