How can I avoid an authentication dialog in Flex when using HTTPService or URLRequest?

Question

This is related to this question. I'm writing a Flex app (a WindowedApplication) that uses REST. Everything's fine when I post with valid authentication, but if I happen to pass an invalid username or password to the REST API (a Twitter REST API, to be specific), an authentication dialog pops up.

That's not a desirable user experience, and it happens both when I use HTTPService and URLRequest. There doesn't seem to be an event I can catch to cancel the dialog.

Here's what my code looks like:

    var request:URLRequest = new URLRequest('http://twitter.com/statuses/update.json');
    request.method = URLRequestMethod.POST;
    var encoder : Base64Encoder = new Base64Encoder();
    encoder.encode(this.user + ':' + this.password);
    request.requestHeaders.push(new URLRequestHeader("Authorization", "Basic " + encoder.toString()));
    var params:Object = new Object();
    params.status = msg;                
    request.data = params;

    var loader:URLLoader = new URLLoader();
    loader.addEventListener(Event.COMPLETE, HandleRequestComplete);
    loader.load(request);

Am I missing something? Is there a better way to approach this?

Answer 1

From the Twitter API Doc here:

suppress_response_codes: If this parameter is present, all responses will be returned with a 200 OK status code - even errors. This parameter exists to accommodate Flash and JavaScript applications running in browsers that intercept all non-200 responses. If used, it's then the job of the client to determine error states by parsing the response body. Use with caution, as those error messages may change.

Answer 2

That is becouse your URLRequest is handling authentication. To avoid that do the next:

request.authenticate = false;

Regards!

Alain.

Answer 3

I don't know if this works in a normal Flex app, but in AIR applications you can set a list of allowed response codes to be considered valid.