Adding the following lines in composer.json:
"psr-4": {
"Google\\AdsApi\\": "vendor/googleads/googleads-php-lib/src/Google/AdsApi",
}
And in my controller I use the following way:
use Google\AdsApi\AdWords\AdWordsServices;
use Google\AdsApi\AdWords\AdWordsSession;
use ....
//Path where the credentials were saved
$path=app_path().'/services/google/adwords/adsapi_php.ini';
// Generate a refreshable OAuth2 credential for authentication.
$oAuth2Credential = (new OAuth2TokenBuilder())
->fromFile($path)
->build();
// Construct an API session configured from a properties file and the OAuth2
// credentials above.
$session = (new AdWordsSessionBuilder())
->fromFile($path)
->withOAuth2Credential($oAuth2Credential)
->build();
...