(AutoIt) Get Google Cloud Storage Access Token using Service Account JSON Private Key

Demonstrates how to get a Google Cloud Storage 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 ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

; 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.
$oFac = ObjCreate("Chilkat.FileAccess")
Local $sJsonKey = $oFac.ReadEntireTextFile("qa_data/googleApi/ChilkatCloud-13a07a2e8b3f.json","utf-8")
If ($oFac.LastMethodSuccess <> True) Then
    ConsoleWrite($oFac.LastErrorText & @CRLF)
    Exit
EndIf

; 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"
; 	}

$oGAuth = ObjCreate("Chilkat.AuthGoogle")
$oGAuth.JsonKey = $sJsonKey

; Choose a scope.
$oGAuth.Scope = "https://www.googleapis.com/auth/cloud-platform"

; Request an access token that is valid for this many seconds.
$oGAuth.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.)
$oGAuth.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.
$oTlsSock = ObjCreate("Chilkat.Socket")
Local $bSuccess = $oTlsSock.Connect("www.googleapis.com",443,True,5000)
If ($bSuccess <> True) Then
    ConsoleWrite($oTlsSock.LastErrorText & @CRLF)
    Exit
EndIf

; Send the request to obtain the access token.
$bSuccess = $oGAuth.ObtainAccessToken($oTlsSock)
If ($bSuccess <> True) Then
    ConsoleWrite($oGAuth.LastErrorText & @CRLF)
    Exit
EndIf

; Examine the access token:
ConsoleWrite("Access Token: " & $oGAuth.AccessToken & @CRLF)

; We're going to save this access token to a file to be used
; by other examples.
$oSbToken = ObjCreate("Chilkat.StringBuilder")
$oSbToken.Append($oGAuth.AccessToken)
$oSbToken.WriteFile("qa_data/tokens/googleCloudStorageAccessToken.txt","utf-8",False)