Google Cloud API - Application Default Credentials - php

Question

I have the following code, modified from Google's documentation:
$GOOGLE_APPLICATION_CREDENTIALS = "./[path].json";
$_ENV["GOOGLE_APPLICATION_CREDENTIALS"] = "./[path].json";
$_SERVER["GOOGLE_APPLICATION_CREDENTIALS"] = "./[path].json";
$projectId = "[my project's ID']";
$client = new Google_Client();
$client->useApplicationDefaultCredentials();
$client->setScopes(['https://www.googleapis.com/auth/books']);
$service = new Google_Service_Books($client);
$results = $service->volumes->listVolumes('Henry David Thoreau');
Yet when I run it it returns the error:
PHP Fatal error: Uncaught exception 'DomainException' with message 'Could not load the default credentials. Browse to https://developers.google.com/accounts/docs/application-default-credentials for more information'
I have tried various configurations, for example changing the path of the file. As you see, I've also done the three different forms of variables that I could immediately think of (two environment, one not).
I'm not quite sure where to look next. Should I look into different ways of setting the environment variable or should I define the path in a different way? What are the correct ways of doing this? Is there any other reason for the error?

Answer 1

You need to use putenv() (http://php.net/manual/en/function.putenv.php) instead of trying to use any of the methods you have used ($_ENV or $_SERVER).
Taken from https://github.com/google/google-api-php-client/blob/master/UPGRADING.md#google_auth_assertioncredentials-has-been-removed
// OR use environment variables (recommended)
putenv('GOOGLE_APPLICATION_CREDENTIALS=/path/to/service-account.json');
$client->useApplicationDefaultCredentials();

Answer 2

I agree with the above answer, but only want to describe if user getting error in php using nlp google:
<?php
error_reporting(E_ALL);
ini_set('display_errors', 1);
# Includes the autoloader for libraries installed with composer
require __DIR__ . '/vendor/autoload.php';
# Imports the Google Cloud client library
use Google\Cloud\Language\LanguageClient;
putenv('GOOGLE_APPLICATION_CREDENTIALS=/home/sgupta/www/practise/nlp/google/cred.json'); //your path to file of cred
//$client->useApplicationDefaultCredentials();
# Your Google Cloud Platform project ID
$projectId = 'nlp-project-nname'; //your project name
# Instantiates a client
$language = new LanguageClient([
'projectId' => $projectId
]);
# The text to analyze
$text = 'Sachin Tendulkar';
# Detects the sentiment of the text
$annotation = $language->analyzeSentiment($text);
$sentiment = $annotation->sentiment();
echo "<pre>";
print_r($annotation); die;
echo 'Text: ' . $text . '
Sentiment: ' . $sentiment['score'] . ', ' . $sentiment['magnitude'];
?>

Answer 3

Use this one it's working for me
# Includes the autoloader for libraries installed with composer
require __DIR__ . '/vendor/autoload.php';
putenv('GOOGLE_APPLICATION_CREDENTIALS=../service-account.json');
$client = new Google_Client();
$client->useApplicationDefaultCredentials();
$client->setScopes(['https://www.googleapis.com/auth/analytics.readonly']);
$client->refreshTokenWithAssertion();
$token = $client->getAccessToken();
$accessToken = $token['access_token'];

Answer 4

Alternatively you can define a path to your json file like this
$client = new Google_Client();
$client->setAuthConfig('/path/to/credentials.json');

Answer 5

Attempt to use the ImageAnnotator like below
When running the code, observe that you get an error:
Could not construct ApplicationDefaultCredentials
solution
putenv("GOOGLE_APPLICATION_CREDENTIALS=/home/netwons/Downloads/AIz.json");
but not work.
OS: Ubuntu
PHP version: 7.2.4
Package name and version: google/cloud-vision 0.19.1
this is code
$imageAnnotator = new ImageAnnotatorClient();
// $client->setAuthConfig('key.json');
# the name of the image file to annotate
$fileName = '2.png';
# prepare the image to be annotated
$image = file_get_contents($fileName);
# performs label detection on the image file
$response = $imageAnnotator->labelDetection($image);
$labels = $response->getLabelAnnotations();
if ($labels) {
echo("Labels:" . PHP_EOL);
foreach ($labels as $label) {
echo($label->getDescription() . PHP_EOL);
}
} else {
echo('No label found' . PHP_EOL);
}

Answer 6

You can pass the following array to your client
[
'credentials' => json_decode(file_get_contents('path_to_your_file_.json')), true)
]
In my case its text to speech client, so it can be following
$textToSpeechClient = new TextToSpeechClient([
'credentials' => json_decode(file_get_contents('path_to_your_file.json')), true)
]);