(AutoIt) Refresh HMRC OAuth2 Access Token

Demonstrates how to refresh an HMRC 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.

; See Get HMRC Access Token 
; for sample code showing how to obtain a HMRC access token for desktop apps.

; It is assumed we previously obtained an OAuth2 access token for HMRC.

$oJsonToken = ObjCreate("Chilkat.JsonObject")
Local $bSuccess = $oJsonToken.LoadFile("qa_data/tokens/hmrc.json")
If ($bSuccess <> True) Then
    ConsoleWrite("Failed to load hmrc.json" & @CRLF)
    Exit
EndIf

; The access token JSON looks something like this:

; {
;   "token_type": "Bearer",
;   "scope": "user_impersonation",
;   "expires_in": "3599",
;   "ext_expires_in": "0",
;   "expires_on": "1524783438",
;   "not_before": "1524779538",
;   "resource": "https://mydomain.api.crm.dynamics.com",
;   "access_token": "...",
;   "refresh_token": "...",
;   "id_token": "..."
; }

$oOauth2 = ObjCreate("Chilkat.OAuth2")

$oOauth2.TokenEndpoint = "https://test-api.service.hmrc.gov.uk/oauth/token"

; Replace these with actual values.
$oOauth2.ClientId = "HMRC-CLIENT-ID"
$oOauth2.ClientSecret = "HMRC-CLIENT-SECRET"

; Get the "refresh_token"
$oOauth2.RefreshToken = $oJsonToken.StringOf("refresh_token")

; Send the HTTP POST to refresh the access token..
$bSuccess = $oOauth2.RefreshAccessToken()
If ($bSuccess <> True) Then
    ConsoleWrite($oOauth2.LastErrorText & @CRLF)
    Exit
EndIf

; Load the access token response into the json object 
$oJsonToken.Load($oOauth2.AccessTokenResponse)

; If an "expires_on" member does not exist, then add the JSON member by
; getting the current system date/time and adding the "expires_in" seconds.
; This way we'll know when the token expires.
If ($oJsonToken.HasMember("expires_on") = False) Then
    $oDtExpire = ObjCreate("Chilkat.CkDateTime")
    $oDtExpire.SetFromCurrentSystemTime()
    $oDtExpire.AddSeconds($oJsonToken.IntOf("expires_in"))
    $oJsonToken.AppendString("expires_on",$oDtExpire.GetAsUnixTimeStr(False))
EndIf

; Save the new JSON access token response to a file.
; The access + refresh tokens contained in this JSON will be needed for the next refresh.
$oSbJson = ObjCreate("Chilkat.StringBuilder")
$oJsonToken.EmitCompact = False
$oJsonToken.EmitSb($oSbJson)
$oSbJson.WriteFile("qa_data/tokens/hmrc.json","utf-8",False)

ConsoleWrite("OAuth2 authorization granted!" & @CRLF)
ConsoleWrite("New Access Token = " & $oOauth2.AccessToken & @CRLF)