(DataFlex) GeoOp OAuth2 Authorisation Code Grant (Public App)

Demonstrates how to get an access token for a GeoOp Third-Party Public Application using the Authorisation Code Grant flow.

Note: This example requires Chilkat v9.5.0.63 or greater.

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

Use ChilkatAx-win32.pkg

Procedure Test
    Handle hoOauth2
    Boolean iSuccess
    String sUrl
    Integer iNumMsWaited
    Handle hoFac
    String sTemp1
    Integer iTemp1
    Boolean bTemp1

    // Note: This example requires Chilkat v9.5.0.63 or greater.

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

    Get Create (RefClass(cComChilkatOAuth2)) To hoOauth2
    If (Not(IsComObjectCreated(hoOauth2))) Begin
        Send CreateComObject of hoOauth2
    End

    // This should match the Site URL configured for your GeoOp Application, such as "http://localhost:3017/"
    Set ComListenPort Of hoOauth2 To 3017

    Set ComAuthorizationEndpoint Of hoOauth2 To "https://login.geoop.com/oauth2/code"
    Set ComTokenEndpoint Of hoOauth2 To "https://login.geoop.com/oauth2/token"

    // Replace the client ID with an actual value.
    Set ComClientId Of hoOauth2 To "GEOOP-CLIENT-ID"
    // The ClientSecret should remain empty for a GeoOp public application
    Set ComClientSecret Of hoOauth2 To ""

    // We need a few special settings for GeoOp
    Set ComScope Of hoOauth2 To "default"
    Set ComCodeChallenge Of hoOauth2 To False
    // Setting LocalHost equal to "none" prevents the "redirect_uri" query param from being sent in the initial HTTP request.
    // Note: The GeoOp Application should still have a redirect URL specified as "http://localhost:3017/", where the port
    // number matches the ListenPort above.
    Set ComLocalHost Of hoOauth2 To "none"

    // Begin the OAuth2 three-legged flow.  This returns a URL that should be loaded in a browser.
    Get ComStartAuth Of hoOauth2 To sUrl
    Get ComLastMethodSuccess Of hoOauth2 To bTemp1
    If (bTemp1 <> True) Begin
        Get ComLastErrorText Of hoOauth2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    // 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 GeoOp account owner would interactively accept or deny the authorization request.
    // System.Diagnostics.Process.Start(url);

    // 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 30 seconds.
    Move 0 To iNumMsWaited
    While ((iNumMsWaited < 30000) And ((ComAuthFlowState(hoOauth2)) < 3))
        Send ComSleepMs To hoOauth2 100
        Move (iNumMsWaited + 100) To iNumMsWaited
    Loop

    // 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.
    Get ComAuthFlowState Of hoOauth2 To iTemp1
    If (iTemp1 < 3) Begin
        Get ComCancel Of hoOauth2 To iSuccess
        Showln "No response from the browser!"
        Procedure_Return
    End

    // 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.
    Get ComAuthFlowState Of hoOauth2 To iTemp1
    If (iTemp1 = 5) Begin
        Showln "OAuth2 failed to complete."
        Get ComFailureInfo Of hoOauth2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComAuthFlowState Of hoOauth2 To iTemp1
    If (iTemp1 = 4) Begin
        Showln "OAuth2 authorization was denied."
        Get ComAccessTokenResponse Of hoOauth2 To sTemp1
        Showln sTemp1
        Procedure_Return
    End

    Get ComAuthFlowState Of hoOauth2 To iTemp1
    If (iTemp1 <> 3) Begin
        Get ComAuthFlowState Of hoOauth2 To iTemp1
        Showln "Unexpected AuthFlowState:" iTemp1
        Procedure_Return
    End

    Showln "OAuth2 authorization granted!"
    Get ComAccessToken Of hoOauth2 To sTemp1
    Showln "Access Token = " sTemp1

    // Save the entire JSON response, which includes the access token, for future calls.
    // The JSON AccessTokenResponse looks like this:
    // {"access_token":"e6dqdG....mzjpT04w==","token_type":"Bearer","expires_in":2592000,"owner_id":984236}

    Get Create (RefClass(cComCkFileAccess)) To hoFac
    If (Not(IsComObjectCreated(hoFac))) Begin
        Send CreateComObject of hoFac
    End
    Get ComAccessTokenResponse Of hoOauth2 To sTemp1
    Get ComWriteEntireTextFile Of hoFac "qa_data/tokens/geoop.json" sTemp1 "utf-8" False To iSuccess

    Showln "Success."


End_Procedure