(AutoIt) Get Firebase Access Token from JSON Service Account Private Key

Demonstrates how to get a Firebase access token using a JSON service account private key. Your Firebase service account can be used to authenticate multiple Firebase features, such as Database, Storage and Auth, programmatically.

A Firebase JSON service account private key can be created in the Firebase settings/admin portion of the console.firebase.google.com site as shown here:

Scroll down to see the example code...

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 Firebase JSON private key into a string.
$oFac = ObjCreate("Chilkat.FileAccess")
Local $sJsonKey = $oFac.ReadEntireTextFile("qa_data/firebase/firebase-chilkat-firebase-adminsdk-n28n4-1b664ee163.json","utf-8")
If ($oFac.LastMethodSuccess <> True) Then
    ConsoleWrite($oFac.LastErrorText & @CRLF)
    Exit
EndIf

; A Firebase JSON private key should look something like this:

; { 
;   "type": "service_account",
;   "project_id": "firebase-chilkat",
;   "private_key_id": "1c664ee164907413c91ddefcf5b765ecba8779e2",
;   "private_key": "-----BEGIN PRIVATE KEY-----\nMIIEvQIBA ... Ya2UZii/lXn73/ZOK8=\n-----END PRIVATE KEY-----\n",
;   "client_email": "firebase-adminsdk-n28n4@firebase-chilkat.iam.gserviceaccount.com",
;   "client_id": "134846322329335418431",
;   "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/firebase-adminsdk-n28n4%40firebase-chilkat.iam.gserviceaccount.com"
; } 
; 

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

; Choose a scope.
; The scope could be "https://www.googleapis.com/auth/firebase.database"
; or a space-delimited list of scopes:
; "https://www.googleapis.com/auth/firebase.database https://www.googleapis.com/auth/userinfo.email"

$oGAuth.Scope = "https://www.googleapis.com/auth/firebase.database https://www.googleapis.com/auth/userinfo.email"

; 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("Firebase Access Token: " & $oGAuth.AccessToken & @CRLF)

; Save the token to a file (or wherever desired).  This token is valid for 1 hour.
$oFac.WriteEntireTextFile("qa_data/tokens/firebaseToken.txt",$oGAuth.AccessToken,"utf-8",False)