(Perl) Get Google Cloud SQL Access Token using Service Account JSON Private Key

Demonstrates how to get a Google Cloud SQL access token using a JSON service account private key. Obtaining an access token for a service account requires no user interaction (it does not require a browser, nor callback URI's, etc.).

When an access token expires, an application can be (and should be) designed to automatically fetch a new access token.

Chilkat Perl Downloads Perl Module for Windows, MacOS, Linux, Alpine Linux, Solaris

use chilkat();

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

# First load the JSON key into a string.
$fac = chilkat::CkFileAccess->new();
$jsonKey = $fac->readEntireTextFile("qa_data/googleApi/ChilkatCloud-13a07a2e8b3f.json","utf-8");
if ($fac->get_LastMethodSuccess() != 1) {
    print $fac->lastErrorText() . "\r\n";
    exit;
}

# A JSON private key should look something like this:

# 	{
# 	  "type": "service_account",
# 	  "project_id": "chilkattest-1350",
# 	  "private_key_id": "fa2e36ee26986eab628b59868af8bec1d1c64c38",
# 	  "private_key": "-----BEGIN PRIVATE KEY-----\nMIIEvgIjFa...28N64N2n1E4FYzBZjSdy\n-----END PRIVATE KEY-----\n",
# 	  "client_email": "598922945226-00rb0ppfg0sndajo6bhvd4v17jtj2d3a@developer.gserviceaccount.com",
# 	  "client_id": "598922945226-00rb0ppfg0snd9jo7bhvd4v17jtj2d3a.apps.googleusercontent.com",
# 	  "auth_uri": "https://accounts.google.com/o/oauth2/auth",
# 	  "token_uri": "https://accounts.google.com/o/oauth2/token",
# 	  "auth_provider_x509_cert_url": "https://www.googleapis.com/oauth2/v1/certs",
# 	  "client_x509_cert_url": "https://www.googleapis.com/robot/v1/metadata/x509/598922945226-00rb0ppfg0sndajo6bhvd4v17jtj2d3a%40developer.gserviceaccount.com"
# 	}

$gAuth = chilkat::CkAuthGoogle->new();
$gAuth->put_JsonKey($jsonKey);

# Choose a scope.
# Here's the OAuth 2.0 scope information for the Cloud SQL Admin API:
# https://www.googleapis.com/auth/sqlservice.admin 	(Read/write access to Cloud SQL.)
# https://www.googleapis.com/auth/cloud-platform 	(Instances.import and Instances.export need this additional scope.)
$gAuth->put_Scope("https://www.googleapis.com/auth/sqlservice.admin");

# Request an access token that is valid for this many seconds.
$gAuth->put_ExpireNumSeconds(3600);

# If the application is requesting delegated access:
# The email address of the user for which the application is requesting delegated access,
# then set the email address here. (Otherwise leave it empty.)
$gAuth->put_SubEmailAddress("");

# Connect to www.googleapis.com using TLS (TLS 1.2 is the default.)
# The Chilkat socket object is used so that the connection can be established
# through proxies or an SSH tunnel if desired.
$tlsSock = chilkat::CkSocket->new();
$success = $tlsSock->Connect("www.googleapis.com",443,1,5000);
if ($success != 1) {
    print $tlsSock->lastErrorText() . "\r\n";
    exit;
}

# Send the request to obtain the access token.
$success = $gAuth->ObtainAccessToken($tlsSock);
if ($success != 1) {
    print $gAuth->lastErrorText() . "\r\n";
    exit;
}

# Examine the access token:
print "Access Token: " . $gAuth->accessToken() . "\r\n";

# Access token looks like this:  ya29.c.Ko4Bwwe3nG5rUvoBmJwadi ... Br4Ogz0B6qLAjg

# We're going to save this access token to a file to be used
# by other examples.
$sbToken = chilkat::CkStringBuilder->new();
$sbToken->Append($gAuth->accessToken());
$sbToken->WriteFile("qa_data/tokens/google_cloud_sql_access_token.txt","utf-8",0);