TwilioEmulator

A Windows C# GUI Twilio Emulator - Designed to make local development of Twilio Applications easier.

The goal is to emulate most of Twilio's functions - including Call control API and basic TWIML Responses , so that you can focus on your call application on your desktop and not have to worry about the cost , and how to get Twilio traffic back to your desktop

Latest Changes

June 8/2014

• Requests are now signed using the AuthToken value in the config file

Note: The RequestValidator that Twilio provides has a .IsLocal opt out - in order to sumulate the request you will need to work around that code

January 10/2014

• You can script call responses form te scripting tab
• Twiml displayed in the Call log
• Double clik on a call log node for more details.

Previous Changes

Connecting from your application

The standard Twilio client does not allow for connections other than the real twilio service. It also forces you to provide the credentials every time you create the client. I have created a companion project called [TwilioDotConfig] (https://github.com/mbadler/TwilioDotConfig) that provides for web/app.config settings to auto configure and redirect the standard twilio client.

Current Status:

• Functionality is currently fully implemeted for Outbound calls.
• SMS implemented.
• Basic Incoming Call Support
• Basic Scripting Ability

Planning

• Planning for Full Phone number purchasing API

Down the road:

• Call list API
• Multiple Phones
• Script phone clients (that respond with scripted digits) (in early beta)
• Headless mode configurable via API call for unit testing external Twilio based applications
• Playing voice files
• Using Windows TTS to play the actual SAY sentences so that you can approximate what the call will sound like
• NEW- Provided complied binaries

How it works:

TwilioEmulator is a windows application that implements a http webserver (WebAPI) to emulate the Twilio Voice Services. When a web application sends a connect call to the API the emulated phone keypad allows the tester to interact with the emulator. The emulator requests Twiml Documents from the server and exeutes them to the emulated phone. it listens to responses from the touch tone pad and relays those back to the server. The server can control the call the executing by calling the redirect or hangup apis. The server receives a call back when the phone call ends or the phone call could not connect The phone can be set to Machine mode and the IfMachine parameter is honored

Incoming phone calls:

Incoming phone calls are being work. Currently any call from the touchpad will go to the default Incoming Phone Number and the default Voice URL. You specify the defualt number and url in the configuration file or by calling the AddIncomingPhoneNumber API call

Outbound SMS Support

When a application calls one of the SMS API's (SMS or ShortCode) or returns the SMS verb in Twiml a message is displayed on the phonelog If a callback was included then the callback is called , The twiml verb can also include a action parameter that will request new TWiml and execute that.

SMS request will alwys return SmsStatus=sent

Twiml Verbs Support:

The following Twiml are planned for support :

Verb	Current Status	Description	Remarks
Say	Implemented	Read text to the caller	via output to the log file or perhaps TTS - loop ignored for now
Play	Implemented	Play an audio file for the caller	via a message on the log stating that the file would be palyed , maybe in the future we will actually download the file and play it over the speaker - loop ignored for now
Gather	Implemented	Collect digits the caller types on their keypad	action url's must be absolute
Sms	Implemented	Send an SMS message during a phone call	A message displayed in the log will indicate it was sent
Hangup	Implemented	Hang up the call
Redirect	Implemented	Redirect call flow to a different TwiML document.
Pause	Implemented	Wait before executing more instructions
Reject	In Progress	Decline an incoming call without being billed.

API Call Support

The following API Calls are currently supported or are planned:

.Net Call	Rest	Status
InitiateOutboundCall	POST /2010-04-01/Accounts/{AccountSid}/Calls	Implemented
GetCall	GET /2010-04-01/Accounts/{AccountSid}/Calls/{CallSid}	Implemeted
HangupCall	POST /2010-04-01/Accounts/{AccountSid}/Calls/{CallSid} "Status"	Impleneted (only Status=completed)
RedirectCall	POST /2010-04-01/Accounts/{AccountSid}/Calls/{CallSid} "URL"	Implemented
SendSmsMessage	POST /2010-04-01/Accounts/{AccountSid}/SMS/Messages	Implemented
AddIncomingPhoneNumber	POST 2010-04-01/Accounts/{AccountSid}/IncomingPhoneNumbers	Planning

Scripting (very early beta)

You can do basic script reponses to (outbound only for now) phone calls. On the script tag fill in the script - the script will be saved to script.txt as you type

Currenly supported script commands

Script Command	Description	Example
WaitFor	Waits for the specified text to be sent from the server (only with a twiml SAY not a PLAY. If the text is sourounded by braces {} it will be matched using regex	WaitFor:Press 1 to continue
Wait	Waits the sepcified number of seconds before moving on to the next instruction	Wait:2
Digits	Sends the sepcified digets back to the server as if it were enterd on the key pad	Digits:1212#

Concurrent Phone Calls:

The emulator is built to support many concurrent calls to many differnt numbers at the same time, however for the time bing there is only one phone active - the touch tone looking thing on the main form , so you can only have one call going at a time. If you make a new call request while a previous one is active you will receive a "BUSY" respone

Manual Phone Statuses:

You can manually set the status you want call requests to return from the toolbar

Current Known And/or Planned Limitations

• Callbacks are POST only
• No security checking at all
• Not all Twiml verbs are supported - see above

Log

Logging is currently to a treeview on the main form of the emulator Each request is marked with a text symbol to show the direction of the call

    () = www , [] = TwilioEmulator } = phone
  

so:

    () --> []  =  Incoming rest API call
    () <-- []  =  Outgoing Twiml request
    [] --> }   =  Request to the phone (dial ,say ) etc...
    [] <-- }   =  phone notifing server (digit keypress, hangup, etc...)
  

For developers using the .Net helper:

The twilio rest client has the address to the twilio servers hard coded. To acess the emulator on local host you can use the TwilioTestClient.cs class which uses reflection to change the underlying address

##change log## August 13

• Inbound calls from the dial pad now work - click on the dial button on the pad and the call will start, specify the voiceurl in the settings

August 12:

• New Http Log Tab , Shows requests received to the API at a Http Level and the results.
• SMS supported , SMS Api calls and SMS verb in Twiml.
• Ground work for inbound calls and Emulator control API.