TXDataWebConnection and Await

[Weetch_Russell (Russell Weetch)]

Further to my question TXDataWebConnection.SendRequest and Await - BIZ / TMS XData - TMS Support Center (tmssoftware.com).

I think I must have missed something here as I am not getting Await to work (I don't run both methods at the same time):

  Conn := TXDataWebConnection.Create(nil);
  try
    //method 1:
    Conn.SendRequest(THttpRequest.Create('config/config.json'), @OnSuccess, @OnError);

    //Method 2:
    Response := Await(IHttpResponse, Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));
    if Response.StatusCode = 200 then
       Config.Load(Response.ContentAsText);
  finally
    Conn.Free;
  end;

Method 1 works, but Method 2 results in

Uncaught (in promise) TypeError: Cannot read properties of undefined (reading 'status')

What have I missed?

[wlandgraf (Wagner Landgraf)]

You syntax is strange:

   Response := Await(IHttpResponse, Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));

It should be just:

   Response := Await(Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));

Maybe you tried to use the Web-Core specific type-safe approach as described here? In this case, it should be this way:

   Response := TAwait.Exec<IHttpResponse>(Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));

[Weetch_Russell (Russell Weetch)]

I used that syntax because I think every example in the TMSWEBCoreDevGuide.pdf uses the format

Await(<ReturnType>, Command);

I have tried the alternatives that you suggest:

Response := Await(Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));

This returned the same exception

Uncaught (in promise) TypeError: Cannot read properties of undefined (reading 'status')

The second alternative:

Response := TAwait.Exec<IHttpResponse>(Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));

When compiled showed as

Response := Await(Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));

when examining the source code in the browser:

In Delphi:

In Browser

So also resulted in the same exception:

[wlandgraf (Wagner Landgraf)]

Can you maybe please send us a small sample project reproducing the issue? It should be simple to reproduce it by requesting any public URL from the internet, isn't it?

[Weetch_Russell (Russell Weetch)]

Here is a test project. It illustrates

1. the conversion of Await.Exec to Await
2. the success on the use Conn.SendRequest(THttpRequest.Create('config/config.json'), @OnSuccess, @OnError);
3. the error in using Response := Await(Conn.SendRequestAsync(THttpRequest.Create('config/config.json')));

WebCoreDemo.zip (1006.2 KB)

[wlandgraf (Wagner Landgraf)]

Sorry, but your project is absolutely empty. There are two data modules in there with no components or code in them.

[Weetch_Russell (Russell Weetch)]

No idea what happened there. Try this one.
Demo.zip (1004.1 KB)

[wlandgraf (Wagner Landgraf)]

Thank you. I see now the issue. You can fix it directly in your code, in unit <xdata>\source\core\web\XData.Web.Connection.pas, method TXDataWebConnection.SendRequestAsync, around line 500, please add the following line:

        procedure(Response: IHttpResponse)
        begin
          Response._AddRef; // ADD THIS LINE
          resolve(Response);
        end,

The fix will be included in next release.