Access to data using Google AdSense Management API - PHP - php

Question

I'm trying to retrieve data from an AdSense account through the AdSense Management API.
I have successfully retrieved data using Google APIs Explorer when connected with my AdSense account.
I am now trying to get this data from a PHP script which will be run in a crontab.
My understanding is that I need a Service account which I created and I generated a json file.
The following code fails if I try to use the json file with two different errors :
if I use the setSubject with the owner of the AdSense account :
"error": "unauthorized_client",
"error_description": "Client is unauthorized to retrieve access tokens using this method."
If I comment the setSubject :
"reason": "noAdSenseAccount",
"message": "User does not have an AdSense account."
Code:
<?php
require_once '../../vendor/autoload.php';
putenv('GOOGLE_APPLICATION_CREDENTIALS=../conf/Mercury-testlpstats.json');
$client = new Google_Client();
$client->useApplicationDefaultCredentials();
$client->addScope('https://www.googleapis.com/auth/adsense.readonly');
//$client->setSubject('AdTech#Lagardere-Pub.com');
$service = new Google_Service_AdSense($client);
$startDate = '2017-05-01';
$endDate = '2017-05-01';
$optParams = array(
'metric' => array('INDIVIDUAL_AD_IMPRESSIONS', 'EARNINGS'),
'dimension' => 'DATE',
'filter' => array('AD_UNIT_ID==ca-pub-XXXX:YYYY'),
'useTimezoneReporting' => true
);
$report = $service->accounts_reports->generate('pub-ZZZZZ', $startDate, $endDate, $optParams);
2nd attempt with OAuth
I've created a OAuth account in https://console.cloud.google.com/apis/credentials/oauthclient/. When I check the AdSense API, my account appears in the list of authorized users in https://console.cloud.google.com/apis/api/adsense.googleapis.com/overview.
I've downloaded the corresponding JSON and changed my code but it still says:
"insufficientPermissions" if I set $client->useApplicationDefaultCredentials();
"Login Required" otherwise
require_once '../../vendor/autoload.php';
$client = new Google_Client();
$client->setAccessType('online');
$client->setAuthConfigFile('/home/al1/lpstats/conf/client_secret_725834039890-klbuc13f8089rjh7eis439b93n7sqqfv.apps.googleusercontent.com.json');
$client->addScope('https://www.googleapis.com/auth/adsense.readonly');
$service = new Google_Service_AdSense($client);
$startDate = '2017-05-01';
$endDate = '2017-05-01';
$optParams = array(
'metric' => array('INDIVIDUAL_AD_IMPRESSIONS', 'EARNINGS'),
'dimension' => 'DATE',
'filter' => array('AD_UNIT_ID==ca-pub-5035025648894332:3442683203'),
'useTimezoneReporting' => true
);
$report = $service->accounts_reports->generate('pub-5035025648894332', $startDate, $endDate, $optParams);

Answer 1

unauthorized_client
Means that the user you are authencating with does not have access to the Adsence Account you are trying to access.
Service account support
There are a number of Google APIs which don't support service accounts. Most noticeably would be YouTube API which does not even have a way of sharing your account with another user.
There are others which will allow you to share your data with another user but require that the user in question respond to an email notification. Blogger is one and Adsence is apparently another.
Solution
You will need to authenticate using Oauth2 using a user who has access to the adsence account in question. Authenticate your code once save the refresh token and use the refresh token to request a new access token within your cron job.