Migrate twilio webhooks to the webhook component (#17715)

* Migrate twilio webhooks to the webhook component

* Fix typos in twilio

* Mock out twilio in the tests

* Lint

* Fix regression in twilio response

tests/components/twilio/test_init.py

@@ -0,0 +1,41 @@
+"""Test the init file of Twilio."""
+from unittest.mock import patch
+
+from homeassistant import data_entry_flow
+from homeassistant.components import twilio
+from homeassistant.core import callback
+from tests.common import MockDependency
+
+
+@MockDependency('twilio', 'rest')
+@MockDependency('twilio', 'twiml')
+async def test_config_flow_registers_webhook(hass, aiohttp_client):
+    """Test setting up Twilio and sending webhook."""
+    with patch('homeassistant.util.get_local_ip', return_value='example.com'):
+        result = await hass.config_entries.flow.async_init('twilio', context={
+            'source': 'user'
+        })
+    assert result['type'] == data_entry_flow.RESULT_TYPE_FORM, result
+
+    result = await hass.config_entries.flow.async_configure(
+        result['flow_id'], {})
+    assert result['type'] == data_entry_flow.RESULT_TYPE_CREATE_ENTRY
+    webhook_id = result['result'].data['webhook_id']
+
+    twilio_events = []
+
+    @callback
+    def handle_event(event):
+        """Handle Twilio event."""
+        twilio_events.append(event)
+
+    hass.bus.async_listen(twilio.RECEIVED_DATA, handle_event)
+
+    client = await aiohttp_client(hass.http.app)
+    await client.post('/api/webhook/{}'.format(webhook_id), data={
+        'hello': 'twilio'
+    })
+
+    assert len(twilio_events) == 1
+    assert twilio_events[0].data['webhook_id'] == webhook_id
+    assert twilio_events[0].data['hello'] == 'twilio'