Receiving a real incoming call in Twilio's ClientQuickstart - twilio

Question

For the time being I use a test account in Twilio, but I hope that this has no relevance regarding my question.
As my firs experimental step towards Twilio, I'm testing the client-quickstart-csharp-1.4 package on Visual Studio 2017 on Windows.
Outgoing calls work fine to my verified phone, but I have problems with incoming calls. When I make a call from a real phone to my Twilio phonenumber, then my code in VoiceController.cs doesn't run (doesn't hit any breakpoint) and I hear a voice message about that I should reconfigure something my application (but I don't understand, what). In contrast of this, when I make a call from my TwiMLApp config page, pressing the red Call button (see picture),
then my code stops at the breakpoints, and says the text I wrote in the argumet of response.Say().
My questions:
Why does the call work differently from a real phone then from my
TwiMLApp config page?
How can I achieve my code run (i.e. say the text I wrote in the code) also when I make a call from a real phone?
How Can I achieve a real, live voice dialogue between the caller phone and my computer's speaker and microphone at incoming calls (similarly to
the outgoing calls)?
Remark 1.
Both outgoing an incoming calls work fine in Agile CRM using the Twilio widget for voice calls. But for the time of my experiments I've removed this widget (and also the "Agile CRM Twilio Saga" TwiML App from Twilio), to avoid the interferences between the different applications.
Remark 2.
Perhaps I should configure something with this screen (the screenshot found here), but I don't find this page on my twilio portal.
Instead of this, I have a page like this:
But I don't know what to change here to make my program work.

Answer 1

It seems that this application is designed
to manage outgoing calls (to a real phone, or to an other client of this
application) and
accept calls from the web (from an another client,
or from the TwiML App setting page, seen on the first screenshot on the o.p.), but not from a real phone.
Every (outgoing or incoming) call falls into the Index() method of the VoiceController class. This method tries to find out whether a call is incoming or outgoing.
In the case of on outgoing call, the To property of the request parameter of this method is a phonenumber, while at an incoming call from the web is a string (a username), or null (when the call comes from the TwiML App setting page). This justifies the if-else structure in the original code (extended just my remarks starting with (mma))
public ActionResult Index(VoiceRequest request)
{
var callerId = ConfigurationManager.AppSettings["TwilioCallerId"];
var response = new TwilioResponse();
if (!string.IsNullOrEmpty(request.To))
{
// wrap the phone number or client name in the appropriate TwiML verb
// by checking if the number given has only digits and format symbols
if (Regex.IsMatch(request.To, "^[\\d\\+\\-\\(\\) ]+$")) //(mma) supposed to be an outgoing call
{
response.Dial(new Number(request.To), new { callerId });
}
else //(mma) a call from one client to antorher
{
response.Dial(new Client(request.To), new { callerId });
}
}
else //(mma) incoming call from the TwiML App setting page
{
response.Say("Thanks for calling!");
}
return TwiML(response);
Question 3. can be separated into the following two parts:
If at an incoming call we want to establish a real connection with a pre-specified client (say calledUser) instead of reading out the "Thanks for calling!" message, we should replace response.Say("Thanks for calling!"); by response.Dial(cl, new { request.From }); where cl = new Client(calledUser); We can put the value of calledUser into our Local.config, so we can read it from there: var calledUser = ConfigurationManager.AppSettings["calledUser"];
If we want to accept a call from a real phone, then we should recognize this situation. This is exactly when request.To == callerId( = our Twilio phononumber) , so we must split the first condition according this. The new branch will call the pre-specified user.
Putting these together, our new code in VoiceController.cs will look like this:
public ActionResult Index(VoiceRequest request)
{
var callerId = ConfigurationManager.AppSettings["TwilioCallerId"];
var calledUser = ConfigurationManager.AppSettings["calledUser"];
var response = new TwilioResponse();
if (!string.IsNullOrEmpty(request.To))
{
// wrap the phone number or client name in the appropriate TwiML verb
// by checking if the number given has only digits and format symbols
if (Regex.IsMatch(request.To, "^[\\d\\+\\-\\(\\) ]+$"))
{
if (request.To != callerId) //(mma) supposed to be an outgoing call
{
response.Dial(new Number(request.To), new { callerId });
}
else //(mma) supposed to be an incoming call from a real phone
{
var cl = new Client(calledUser);
response.Dial(cl, new { request.From });
}
}
else //(mma) a call from one client to antorher
{
response.Dial(new Client(request.To), new { request.From });
}
}
else //(mma) incoming call from the TwiML App setting page
{
var cl = new Client(calledUser);
response.Dial(cl, new { request.From });
}
return TwiML(response);
}
Of course, if we want to accept a call, then we should start a client with the pre-defined username (calledUser). In order to do this, we can introduce a new Url parameter User, put its value into TempData["User"] by the HomeController and change the var identity = Internet.UserName().AlphanumericOnly(); line in the TokenController.cs to var identity = TempData["User"] == null ? Internet.UserName().AlphanumericOnly() : TempData["User"].ToString();
So, our new HomeController and TokenController look like this:
public class HomeController : Controller
{
public ActionResult Index(string user)
{
TempData["User"] = user;
return View();
}
}
and this:
public class TokenController : Controller
{
// GET: /token
public ActionResult Index()
{
// Load Twilio configuration from Web.config
var accountSid = ConfigurationManager.AppSettings["TwilioAccountSid"];
var authToken = ConfigurationManager.AppSettings["TwilioAuthToken"];
var appSid = ConfigurationManager.AppSettings["TwilioTwimlAppSid"];
// Create a random identity for the client
var identity = TempData["User"] == null ? Internet.UserName().AlphanumericOnly() : TempData["User"].ToString();
// Create an Access Token generator
var capability = new TwilioCapability(accountSid, authToken);
capability.AllowClientOutgoing(appSid);
capability.AllowClientIncoming(identity);
var token = capability.GenerateToken();
return Json(new
{
identity,
token
}, JsonRequestBehavior.AllowGet);
}
}
And, of course, our Local.config file should contain such a line:
<add key="calledUser" value="TheNameOfThePreDefinedUser" />