src/Google/AccessToken/Revoke.php
public function revokeToken($token)
  {
    if (is_array($token)) {
      if (isset($token['refresh_token'])) {
        $token = $token['refresh_token'];
      } else {
        $token = $token['access_token'];
      }
    }

    $body = Psr7\stream_for(http_build_query(array('token' => $token)));
    $request = new Request(
        'POST',
        Google_Client::OAUTH2_REVOKE_URI,
        [
          'Cache-Control' => 'no-store',
          'Content-Type'  => 'application/x-www-form-urlencoded',
        ],
        $body
    );

    $httpHandler = HttpHandlerFactory::build($this->http);

    $response = $httpHandler($request);

    return $response->getStatusCode() == 200;
  }
public function revokeToken($token)
  {
    if (is_array($token)) {
      if (isset($token['refresh_token'])) {
        $token = $token['refresh_token'];
      } else {
        $token = $token['access_token'];
      }
    }

    $body = Psr7\stream_for(http_build_query(array('token' => $token)));
    $request = new Request(
        'POST',
        Google_Client::OAUTH2_REVOKE_URI,
        [
          'Cache-Control' => 'no-store',
          'Content-Type'  => 'application/x-www-form-urlencoded',
        ],
        $body
    );

    $httpHandler = HttpHandlerFactory::build($this->http);

    $response = $httpHandler($request);

    return $response->getStatusCode() == 200;
  }
Revoke an OAuth2 access token or refresh token. This method will revoke the current access
token, if a token isn't provided.

@param string|array $token The token (access token or a refresh token) that should be revoked.
@return boolean Returns True if the revocation was successful, otherwise False.