(PHP Extension) Refresh Access Token on 401 Unauthorized and Retry (Service Account)

See more Google Cloud Storage Examples

Chilkat PHP Downloads PHP Extension for Windows, Linux, MacOS, Alpine Linux

<?php

include("chilkat.php");
// Use "chilkat_9_5_0.php" for versions of Chilkat < 10.0.0

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

// This example uses a previously obtained access token having permission for the 
// scope "https://www.googleapis.com/auth/cloud-platform"

// In this example, Get Google Cloud Storage OAuth2 Access Token, 
// the service account access token was saved to a text file.  This example fetches the access token from the file..
$sbToken = new CkStringBuilder();
$success = $sbToken->LoadFile('qa_data/tokens/googleCloudStorageAccessToken.txt','utf-8');
if ($success == false) {
    print 'Failed to load access token.' . "\n";
    exit;
}

$http = new CkHttp();

$http->put_AuthToken($sbToken->getAsString());

// Construct a URL to download an object named "starfish.jpg" from the "chilkat-ocean" bucket.
$http->SetUrlVar('bucket_name','chilkat-ocean');
$http->SetUrlVar('object_name','starfish.jpg');
$url = 'https://www.googleapis.com/storage/v1/b/{$bucket_name}/o/{$object_name}?alt=media';

// If there is an error response, then we didn't actually download the file data,
// but instead we downloaded an error response..
$fileData = new CkBinData();
$success = $http->DownloadBd($url,$fileData);
$responseCode = $http->get_LastStatus();
if (($success == false) and ($responseCode != 401)) {
    print $http->lastErrorText() . "\n";
    exit;
}

if ($responseCode == 401) {
    print 'Received 401 Unauthorized response. Attempting to refresh the access token...' . "\n";

    // May be that the access token expired.
    // Load our JSON key and request a new access token, then retry the original request.
    $fac = new CkFileAccess();
    $jsonKey = $fac->readEntireTextFile('qa_data/googleApi/ChilkatCloud-13a07a2e8b3f.json','utf-8');
    if ($fac->get_LastMethodSuccess() != true) {
        print $fac->lastErrorText() . "\n";
        exit;
    }

    $gAuth = new CkAuthGoogle();
    $gAuth->put_JsonKey($jsonKey);
    $gAuth->put_Scope('https://www.googleapis.com/auth/cloud-platform');
    $gAuth->put_ExpireNumSeconds(3600);
    $gAuth->put_SubEmailAddress('');

    $tlsSock = new CkSocket();
    $success = $tlsSock->Connect('www.googleapis.com',443,true,5000);
    if ($success != true) {
        print $tlsSock->lastErrorText() . "\n";
        exit;
    }

    $success = $gAuth->ObtainAccessToken($tlsSock);
    if ($success != true) {
        print $gAuth->lastErrorText() . "\n";
        exit;
    }

    $fac->WriteEntireTextFile('qa_data/tokens/googleCloudStorageAccessToken.txt',$gAuth->accessToken(),'utf-8',false);

    // Retry the original request.
    $http->put_AuthToken($gAuth->accessToken());
    $success = $http->DownloadBd($url,$fileData);
    if ($success == false) {
        print $http->lastErrorText() . "\n";
        exit;
    }

}

if ($responseCode != 200) {
    // Get the error response
    $sbErrorResponse = new CkStringBuilder();
    $sbErrorResponse->AppendBd($fileData,'utf-8',0,0);
    print 'Error response code = ' . $responseCode . "\n";
    print 'Error:' . "\n";
    print $sbErrorResponse->getAsString() . "\n";
    exit;
}

print 'Success.' . "\n";

// Save the downloaded data to a file.
$success = $fileData->WriteFile('qa_output/starfish.jpg');

?>