Delphi XE Indy connects to local server api but not public server api

Question

I am having issues connecting to a public domain api with Indy Client using Delphi XE.

I can connect successfully to my localhost web server api (apache) successfully but a similar attempt to a remote server (public domain) on shared hosting gives me a forbidden 403 error.

I can access the same public domain api using cURL successfully. Therefore I ruled out anything any issues with rights/firewall on the shared hosting server.

    function CallService(ServiceID: string;payload:string): string;
    var
      JsonToSend: TStringStream;
      ServerResponse,EndPointURL: string;
      LastJSONArray: TStringList;
      MyIndy : TIdHTTP;
    begin

     //Local connection WORKS :)
     EndPointURL := 'http://localhost/api/index.php';

     //Remote/Public Domain connection FAILS :(
     EndPointURL := 'http://example.com/api/index.php';

     LastJSONArray := TStringList.Create();

     LastJSONArray.Values['service_id'] := ServiceID;
     LastJSONArray.Values['payload'] := payload;

     JsonToSend := TStringStream.Create(LastJSONArray.Text, TEncoding.UTF8);

      MyIndy := TIdHTTP.Create;

      try

        try

          MyIndy.Request.Accept := 'application/json';
          MyIndy.Request.ContentType := 'application/json';
          MyIndy.Request.ContentEncoding := 'utf-8';        

          ServerResponse := MyIndy.Post(EndPointURL, JsonToSend);

          Result := ServerResponse;

         except
          on E: EIdHTTPProtocolException do
           //status := http.ResponseText;
           //code := E.ErrorCode;
           if E.ErrorCode = 401 then ShowMessage('You are not authorised!')
           else ShowMessage('Poor Connection '+E.Message);

          on E: Exception do begin
            //do something else
            ShowMessage('Poor Connection - B');
          end;

        end;

      finally
        MyIndy.Free();
        JsonToSend.Free();
        LastJSONArray.Free();
      end;

    end;

Is there property/setting with the TIdHTTP Indy component that i need to set/adjust before calling the public api?

Answer 1

After quite some research I found a solution to my problem on the Indy Knowledge Base.

http://www.indyproject.org/KB/iamgettinga403forbiddene.htm

I changed the UserAgent property of my indy component from the default

Mozilla/3.0 (compatible; Indy Library)

and it works!.