(AutoIt) HMRC OAuth2 Access Token

Demonstrates how to get an HMRC OAuth2 access token from a desktop (installed) application or script. This example gets an HMRC MTD VAT read/write 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.

$oOauth2 = ObjCreate("Chilkat.OAuth2")
Local $bSuccess

; This should be the port in the localhost callback URL for your app.
; Important: Make sure the callback URI in your HMRC developer app 
; is exactly "http://localhost:3017/".  Don't forget the ending "/" char.
; The callback URL would look like "http://localhost:3017/" if the port number is 3017.

; IMPORTANT: Don't forget to setup your HMRC application to use the Redirect URI "http://localhost:3017/" as shown
; here: Configure Redirect URI for HMRC application
$oOauth2.ListenPort = 3017

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

; The scopes are documented in the HMRC reference documentation for each API.
; This example gets a read/write access token for the HMRC MTD VAT API.
$oOauth2.Scope = "read:vat write:vat"

; Begin the OAuth2 three-legged flow.  This returns a URL that should be loaded in a browser.
Local $sUrl = $oOauth2.StartAuth()
If ($oOauth2.LastMethodSuccess <> True) Then
    ConsoleWrite($oOauth2.LastErrorText & @CRLF)
    Exit
EndIf

$oHttp = ObjCreate("Chilkat.Http")

; At this point, your application should load the URL in a browser.
; For example, 
; in C#: System.Diagnostics.Process.Start(url);
; in Java: Desktop.getDesktop().browse(new URI(url));
; in VBScript: Set wsh=WScript.CreateObject("WScript.Shell")
;              wsh.Run url
; in Xojo: ShowURL(url)  (see http://docs.xojo.com/index.php/ShowURL)
; in Dataflex: Runprogram Background "c:\Program Files\Internet Explorer\iexplore.exe" sUrl        
; The GitHub account owner would interactively accept or deny the authorization request.

; Add the code to load the url in a web browser here...
; Add the code to load the url in a web browser here...
; Add the code to load the url in a web browser here...

; Now wait for the authorization.
; We'll wait for a max of 120 seconds.
Local $iNumMsWaited = 0
While ($iNumMsWaited < 120000) And ($oOauth2.AuthFlowState < 3)
    $oOauth2.SleepMs 100
    $iNumMsWaited = $iNumMsWaited + 100
Wend

; If there was no response from the browser within 30 seconds, then 
; the AuthFlowState will be equal to 1 or 2.
; 1: Waiting for Redirect. The OAuth2 background thread is waiting to receive the redirect HTTP request from the browser.
; 2: Waiting for Final Response. The OAuth2 background thread is waiting for the final access token response.
; In that case, cancel the background task started in the call to StartAuth.
If ($oOauth2.AuthFlowState < 3) Then
    $oOauth2.Cancel()
    ConsoleWrite("No response from the browser!" & @CRLF)
    Exit
EndIf

; Check the AuthFlowState to see if authorization was granted, denied, or if some error occurred
; The possible AuthFlowState values are:
; 3: Completed with Success. The OAuth2 flow has completed, the background thread exited, and the successful JSON response is available in AccessTokenResponse property.
; 4: Completed with Access Denied. The OAuth2 flow has completed, the background thread exited, and the error JSON is available in AccessTokenResponse property.
; 5: Failed Prior to Completion. The OAuth2 flow failed to complete, the background thread exited, and the error information is available in the FailureInfo property.
If ($oOauth2.AuthFlowState = 5) Then
    ConsoleWrite("OAuth2 failed to complete." & @CRLF)
    ConsoleWrite($oOauth2.FailureInfo & @CRLF)
    Exit
EndIf

If ($oOauth2.AuthFlowState = 4) Then
    ConsoleWrite("OAuth2 authorization was denied." & @CRLF)
    ConsoleWrite($oOauth2.AccessTokenResponse & @CRLF)
    Exit
EndIf

If ($oOauth2.AuthFlowState <> 3) Then
    ConsoleWrite("Unexpected AuthFlowState:" & $oOauth2.AuthFlowState & @CRLF)
    Exit
EndIf

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

; Get the full JSON response:
$oJson = ObjCreate("Chilkat.JsonObject")
$oJson.Load($oOauth2.AccessTokenResponse)
$oJson.EmitCompact = False
ConsoleWrite($oJson.Emit() & @CRLF)

; The JSON response looks 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": "..."
; }

; 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 ($oJson.HasMember("expires_on") <> True) Then
    $oDtExpire = ObjCreate("Chilkat.CkDateTime")
    $oDtExpire.SetFromCurrentSystemTime()
    $oDtExpire.AddSeconds($oJson.IntOf("expires_in"))
    $oJson.AppendString("expires_on",$oDtExpire.GetAsUnixTimeStr(False))
EndIf

ConsoleWrite($oJson.Emit() & @CRLF)

; Save the JSON to a file for future requests.
$oFac = ObjCreate("Chilkat.FileAccess")
$oFac.WriteEntireTextFile("qa_data/tokens/hmrc.json",$oJson.Emit(),"utf-8",False)