Voice - Set up a call with number masking

from typing import Optional
from json import dumps

from bottle import run, request, post

# This is a an example response to an incoming_call Event
# {
#     "method": "dial",
#     "params": {
#         "caller_id_number": "18888888888", # this is your masking ID
#         "to": "19999999999",  # this is the destination number
#         "external_id": "4142b474-d65d-4265-a5fa-a581b1fe6101" # optional parameter
#     }
# }

class TelesignEvent:
    """
    Events that Telesign Voice sends.
    """
    INCOMING = "incoming_call"
    CALL_COMPLETED = "call_completed"
    ANSWERED = "dial_completed"
    PLAY_COMPLETED = "play_completed"
    SPEAK_COMPLETED = "speak_completed"

class DialCommand:
    def __init__(self, to: str, caller_id_number: str, external_id: str= None): # external_id is optional parameter
        self.method: str = 'dial'
        self.to: str = to
        self.caller_id_number: str = caller_id_number
        self.external_id: str = external_id

    def generate_response(self):
        params = {
            'caller_id_number': self.caller_id_number,
            'to': self.to
        }
        if self.external_id is not None:
        params['external_id'] = self.external_id
        
        return Response(method=self.method,
                        params=params).to_json()

class SpeakCommand:
    def __init__(self, tts_message: str, language=Optional[str], collect_digits: bool=False, digits_to_collect: int=1, timeout: int=10000, inter_digit_timeout: int=3000):
        self.method: str = 'speak'
        self.tts_message: str = tts_message
        self.language: str = language
        self.collect_digits = None
        if collect_digits:
            self.collect_digits = {
                'collect_digits': {
                    'max': digits_to_collect,
                    'timeout': timeout,
                    'inter_digit_timeout': inter_digit_timeout
                }
            }

    def generate_response(self):
        params = {
            "tts": {
                "message": self.tts_message,
                "language": self.language
          }
        }
        if self.collect_digits:
            params.update(**self.collect_digits)

        return Response(method=self.method,
                        params=params).to_json()
class HangupCommand:
    def __init__(self):
        self.method = 'hangup'

    def generate_response(self):
        return Response(method=self.method,
                        params={}).to_json()
class Response:

    def __init__(self, method, params=None):
        if params is None:
            params = {}

        self.method = method
        self.params = params

    def to_json(self):
        return dumps(self.__dict__)

@post('/')
def telesign_event():
    # Throughout a call session Telesign sends Event notifications.
    # Each Event can be responded to with a supported Action.
    #
    # In this example, the server responds to the incoming call Event.

    # First extract the Event from the JSON body in the request.
    event = request.json.get('event')

    if event == TelesignEvent.INCOMING:
        # Respond to this event with a dial command.
        caller_id_number = '18888888888' # This is the masking number
        destination_number = '19999999999'
        external_id = '4142b474-d65d-4265-a5fa-a581b1fe6101' # Optional parameter

        # Generate the Action to send to Telesign. Refer to the Voice reference documentation for details.
        return DialCommand(to=destination_number,
            caller_id_number=caller_id_number, external_id = external_id).generate_response()

    elif event == TelesignEvent.ANSWERED:
        return SpeakCommand(tts_message='Thanks for using Telesign',
                            language="en-US",
                            collect_digits=True).generate_response()
    else:
        # You do not know the number.
        return HangupCommand().generate_response()

run(host='localhost', port=8080, debug=True)