(DataFlex) Microsoft Graph OAuth2 Client Credentials Grant Flow

Demonstrates how to get a Microsoft Graph access token using the Client Credentials Grant Flow.

You can use the OAuth 2.0 client credentials grant specified in RFC 6749, sometimes called two-legged OAuth, to access web-hosted resources by using the identity of an application. This type of grant is commonly used for server-to-server interactions that must run in the background, without immediate interaction with a user. These types of applications are often referred to as daemons or service accounts.

For more information, see https://docs.microsoft.com/en-us/azure/active-directory/develop/v2-oauth2-client-creds-grant-flow

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoHttp
    Variant vReq
    Handle hoReq
    String sUrl
    Variant vResp
    Handle hoResp
    Integer iStatusCode
    Handle hoJson
    Boolean iSuccess
    String sTemp1
    Boolean bTemp1

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

    Get Create (RefClass(cComChilkatHttp)) To hoHttp
    If (Not(IsComObjectCreated(hoHttp))) Begin
        Send CreateComObject of hoHttp
    End

    Get Create (RefClass(cComChilkatHttpRequest)) To hoReq
    If (Not(IsComObjectCreated(hoReq))) Begin
        Send CreateComObject of hoReq
    End
    Send ComAddParam To hoReq "client_secret" "CLIENT_SECRET"
    Send ComAddParam To hoReq "client_id" "CLIENT_ID"
    // Don't know if the scopes valid for the client credentials grant are different than the scopes for the 3-legged Authorization Code Grant...
    Send ComAddParam To hoReq "scope" "https://graph.microsoft.com/.default"
    Send ComAddParam To hoReq "grant_type" "client_credentials"

    // Use your own tenant ID, for example 4d8fdd66-66d1-43b0-ae5c-e31b4b7de5cd
    Move "https://login.microsoftonline.com/TENANT_ID/oauth2/v2.0/token" To sUrl
    Get pvComObject of hoReq to vReq
    Get ComPostUrlEncoded Of hoHttp sUrl vReq To vResp
    If (IsComObject(vResp)) Begin
        Get Create (RefClass(cComChilkatHttpResponse)) To hoResp
        Set pvComObject Of hoResp To vResp
    End
    Get ComLastMethodSuccess Of hoHttp To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoHttp To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComStatusCode Of hoResp To iStatusCode
    Showln "Response status code = " iStatusCode

    Get Create (RefClass(cComChilkatJsonObject)) To hoJson
    If (Not(IsComObjectCreated(hoJson))) Begin
        Send CreateComObject of hoJson
    End
    Get ComBodyStr Of hoResp To sTemp1
    Get ComLoad Of hoJson sTemp1 To iSuccess
    Send Destroy of hoResp

    Set ComEmitCompact Of hoJson To False
    Get ComEmit Of hoJson To sTemp1
    Showln sTemp1

    // Sample successful output:

    // {
    //   "token_type": "Bearer",
    //   "expires_in": 3599,
    //   "ext_expires_in": 3599,
    //   "access_token": "eyJ0eX...K0jOERg"
    // }

    If (iStatusCode = 200) Begin
        Get ComWriteFile Of hoJson "qa_data/tokens/msGraphClientCredentialsToken.json" To iSuccess
        Showln "Success."
    End
    Else Begin
        Showln "Failed."
    End



End_Procedure