AutoIt

Google Calendar -- Refresh an Expired Access Token

See more Google Calendar Examples

Demonstrates how to refresh an expired access token. If a Google Calendar REST API call results in a 401 "unauthorized" response, then it is likely the access token expired. An application should be able to automatically refresh the access token with no user interaction and then re-try the request with the newly obtained access token. AutoIt

Local $bSuccess = False

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

;  It is assumed we previously obtained an OAuth2 access token.
;  This example loads the JSON access token file 
;  saved by this example: Get Google Calendar OAuth2 Access Token

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

;  The access token JSON looks like this:

;  	{ 
;  	 "access_token": "abac.Ci-ZabcdF37-NUrmSzxbHxTsMbtlN-uPfabcdAQN_2ekzj0s5ofCzRabcdTDMGaa2Q",
;  	 "token_type": "Bearer",
;  	 "expires_in": 3600,
;  	 "refresh_token": "1/lEe5abcdNJ77eOSDBabcdkQGVmDalkwabcdR2Hatbo"
;  	}
;  

$oOauth2 = ObjCreate("Chilkat.OAuth2")

$oOauth2.TokenEndpoint = "https://www.googleapis.com/oauth2/v4/token"

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

;  The response contains a new access token, but we must keep
;  our existing refresh token for when we need to refresh again in the future.
$oJsonToken.UpdateString("access_token",$oOauth2.AccessToken)

;  Save the new JSON access token response to a file.
$oSbJson = ObjCreate("Chilkat.StringBuilder")
$oJsonToken.EmitCompact = False
$oJsonToken.EmitSb($oSbJson)
$oSbJson.WriteFile("qa_data/tokens/googleCalendar.json","utf-8",False)

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