# Webhooks for external integrations.
from typing import Any, Dict, Text

from django.http import HttpRequest, HttpResponse
from django.utils.translation import ugettext as _

from zerver.decorator import api_key_only_webhook_view
from zerver.lib.actions import check_send_stream_message
from zerver.lib.request import REQ, has_request_variables
from zerver.lib.response import json_error, json_success
from zerver.models import UserProfile

CRASHLYTICS_SUBJECT_TEMPLATE = '{display_id}: {title}'
CRASHLYTICS_MESSAGE_TEMPLATE = '[Issue]({url}) impacts at least {impacted_devices_count} device(s).'

CRASHLYTICS_SETUP_SUBJECT_TEMPLATE = "Setup"
CRASHLYTICS_SETUP_MESSAGE_TEMPLATE = "Webhook has been successfully configured."

VERIFICATION_EVENT = 'verification'


@api_key_only_webhook_view('Crashlytics')
@has_request_variables
def api_crashlytics_webhook(request, user_profile, payload=REQ(argument_type='body'),
                            stream=REQ(default='crashlytics')):
    # type: (HttpRequest, UserProfile, Dict[str, Any], Text) -> HttpResponse
    event = payload['event']
    if event == VERIFICATION_EVENT:
        subject = CRASHLYTICS_SETUP_SUBJECT_TEMPLATE
        body = CRASHLYTICS_SETUP_MESSAGE_TEMPLATE
    else:
        issue_body = payload['payload']
        subject = CRASHLYTICS_SUBJECT_TEMPLATE.format(
            display_id=issue_body['display_id'],
            title=issue_body['title']
        )
        body = CRASHLYTICS_MESSAGE_TEMPLATE.format(
            impacted_devices_count=issue_body['impacted_devices_count'],
            url=issue_body['url']
        )

    check_send_stream_message(user_profile, request.client, stream,
                              subject, body)
    return json_success()

@@ -857,16 +857,29 @@
 (request
+: HttpRequest
 , user_p
@@ -888,17 +888,74 @@
 file
-, payload
+: UserProfile,%0A                            payload: Dict%5Bstr, Any%5D
 =REQ
@@ -1012,16 +1012,22 @@
   stream
+: Text
 =REQ(def
@@ -1050,70 +1050,8 @@
 s'))
-:%0A    # type: (HttpRequest, UserProfile, Dict%5Bstr, Any%5D, Text)
  -%3E 
@@ -1062,16 +1062,17 @@
 Response
+:
 %0A    eve

Use Python 3 type syntax in crashlytics/view.py