Twilio test SMS does not result StatusCallback

Question

I noticed that when I send a test SMS with the Twilio API, everything works as described in the documentation but the StatusCallback is not invoked by the system. The same setting works fine with the real credentials, I get the callback. Is this the expected behavior?

This is how I send the SMS:

/* Test credentials */ 
var account_sid = "<<test acc>>";        
var auth_token = "<<test auth>>";
var fromNumber = "+15005550006"; // test number

var fromNumberEnc = encodeURIComponent(fromNumber); 
var toNumberEnc = encodeURIComponent(toNumber);
var textEnc = encodeURIComponent(text);
var body = "From=" + fromNumberEnc + "&To=" + toNumberEnc + "&Body=" + textEnc + "&StatusCallback=" + "https%3A%2F%2Fexample.com%2Ftwiliocallback";
    httpRequest.post({
        url: "https://" + account_sid + ":" + auth_token +
             "@api.twilio.com/2010-04-01/Accounts/" + account_sid + "/SMS/Messages.json",
        headers: { 'content-type': 'application/x-www-form-urlencoded' },
        body: body
    }, function (err, resp, body) {
        console.log(body);
    });

Answer 1

Rob from Twilio here.

Great question here on using Twilio's test credentials when building against the SMS API. You are correct - StatusCallbacks do not fire for the Messages resource when invoked with test credentials. The documentation section on StatusCallback you reference indicates that the API response will return the value you set for the StatusCallback parameter when testing a phone number purchase, not creating a message or phone call.

I test for StatusCallbacks by mocking the StatusCallback request inside my test using the parameters from the documentation here. The relevant parameter you want to test against on the new Messages resource is MessageStatus.