Visual FoxPro

Get OAuth2 Access Token for Azure Registered App

See more OAuth2 Examples

Demonstrates how to get OAuth2 access token for an Azure Registered App from a desktop application or script. This example demonstrates the OAuth2 authorization flow.

This example requires Chilkat v10.1.2 or greater.

Visual FoxPro

LOCAL lnSuccess
LOCAL loOauth2
LOCAL lcUrl
LOCAL lnNumMsWaited
LOCAL loJson
LOCAL loDtExpire
LOCAL loFac

lnSuccess = 0

* To further clarify, see OAuth 2.0 Authorization Flow

loOauth2 = CreateObject('Chilkat.OAuth2')

* This should be the port in the localhost callback URL for your app.  
* The callback URL would look like "http://localhost:3017/" if the port number is 3017.
loOauth2.ListenPort = 3017

* ----------------------------------------------------------------------------------------------------------
* The screenshot at the bottom of this page shows how we created the Azure App Registration for this example.
* ----------------------------------------------------------------------------------------------------------

* Note: The endpoint depends on the Azure App Registration.
* See How to Choose the Correct Endpoints for your Azure App Registration
loOauth2.AuthorizationEndpoint = "https://login.microsoftonline.com/common/oauth2/v2.0/authorize"
loOauth2.TokenEndpoint = "https://login.microsoftonline.com/common/oauth2/v2.0/token"

* Replace these with actual values.
loOauth2.ClientId = "CLIENT_ID"

* This is for Require Proof Key for Code Exchange (PKCE)
* See OAuth2 PKCE Explained
loOauth2.CodeChallenge = 1
loOauth2.CodeChallengeMethod = "S256"

* Provide a SPACE separated list of scopes.
* See https://developer.microsoft.com/en-us/graph/docs/authorization/permission_scopes 

* Important: To get a refresh token in the final response, ask for "offline_access" scope
loOauth2.Scope = "openid profile offline_access user.readwrite mail.readwrite mail.send files.readwrite"

* Begin the OAuth2 three-legged flow.  This returns a URL that should be loaded in a browser.
lcUrl = loOauth2.StartAuth()
IF (loOauth2.LastMethodSuccess <> 1) THEN
    ? loOauth2.LastErrorText
    RELEASE loOauth2
    CANCEL
ENDIF

* Launch the default browser on the system and navigate to the url.
* The LaunchBrowser method was added in Chilkat v10.1.2.
lnSuccess = loOauth2.LaunchBrowser(lcUrl)
IF (lnSuccess = 0) THEN
    ? loOauth2.LastErrorText
    RELEASE loOauth2
    CANCEL
ENDIF

* Wait for the user to approve or deny authorization in the browser.
lnNumMsWaited = 0
DO WHILE (lnNumMsWaited < 90000) AND (loOauth2.AuthFlowState < 3)
    loOauth2.SleepMs(100)
    lnNumMsWaited = lnNumMsWaited + 100
ENDDO

* If the browser does not respond within the specified time, AuthFlowState will be:
* 
* 1: Waiting for Redirect – The OAuth2 background thread is waiting for the browser's redirect request.
* 2: Waiting for Final Response – The thread is awaiting the final access token response.
* In either case, cancel the background task initiated by StartAuth.

IF (loOauth2.AuthFlowState < 3) THEN
    loOauth2.Cancel()
    ? "No response from the browser!"
    RELEASE loOauth2
    CANCEL
ENDIF

* Check AuthFlowState to determine if authorization was granted, denied, or failed:
* 
* 3: Success – OAuth2 flow completed, the background thread exited, and the successful response is in AccessTokenResponse.
* 4: Access Denied – OAuth2 flow completed, the background thread exited, and the error response is in AccessTokenResponse.
* 5: Failure – OAuth2 flow failed before completion, the background thread exited, and error details are in FailureInfo.

IF (loOauth2.AuthFlowState = 5) THEN
    ? "OAuth2 failed to complete."
    ? loOauth2.FailureInfo
    RELEASE loOauth2
    CANCEL
ENDIF

IF (loOauth2.AuthFlowState = 4) THEN
    ? "OAuth2 authorization was denied."
    ? loOauth2.AccessTokenResponse
    RELEASE loOauth2
    CANCEL
ENDIF

IF (loOauth2.AuthFlowState <> 3) THEN
    ? "Unexpected AuthFlowState:" + STR(loOauth2.AuthFlowState)
    RELEASE loOauth2
    CANCEL
ENDIF

? "OAuth2 authorization granted!"
? "Access Token = " + loOauth2.AccessToken

* When the token is near expiration, your app can refresh as shown here:
* Refresh Expiring OAuth2 Access Token for Azure Registered App

* Get the full JSON response:
loJson = CreateObject('Chilkat.JsonObject')
loJson.Load(loOauth2.AccessTokenResponse)
loJson.EmitCompact = 0

* The JSON response looks like this:

* {
*   "token_type": "Bearer",
*   "scope": "User.Read Mail.ReadWrite Mail.Send",
*   "expires_in": 3600,
*   "ext_expires_in": 0,
*   "access_token": "EwBAA8l6B...",
*   "refresh_token": "MCRMdbe...",
*   "id_token": "eyJ0eXA..."
* }

* 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 (loJson.HasMember("expires_on") <> 1) THEN
    loDtExpire = CreateObject('Chilkat.CkDateTime')
    loDtExpire.SetFromCurrentSystemTime()
    loDtExpire.AddSeconds(loJson.IntOf("expires_in"))
    loJson.AppendString("expires_on",loDtExpire.GetAsUnixTimeStr(0))
ENDIF

? loJson.Emit()

* Save the JSON to a file for future requests.
loFac = CreateObject('Chilkat.FileAccess')
loFac.WriteEntireTextFile("qa_data/tokens/_myAzureApp.json",loJson.Emit(),"utf-8",0)

* This is a screenshot of how we created the Azure App for this example:
* 

RELEASE loOauth2
RELEASE loJson
RELEASE loDtExpire
RELEASE loFac