Allow to configure task handler (#28)

Previously, every task was sent as AWS event, which caused error for
local environment setup.

Now, there is possibility to set different handler, e.g. one that prints
every task to stdout and nothing more.

services/backend/common/__init__.py

@@ -1,2 +1 @@
 from .emails import SendEmail, EmailParams  # noqa
-from .tasks import Task  # noqa

services/backend/common/emails.py

@@ -1,6 +1,10 @@
+import importlib
 from dataclasses import dataclass, asdict
 
-from .tasks import Task
+from django.conf import settings
+
+module_name, package = settings.TASKS_BASE_HANDLER.rsplit(".", maxsplit=1)
+Task = getattr(importlib.import_module(module_name), package)
 
 
 @dataclass

services/backend/common/tasks.py

@@ -11,16 +11,23 @@ def __init__(self, name: str, source: str, event_bus_name=settings.WORKERS_EVENT
         self.source = source
         self.event_bus_name = event_bus_name
 
+    def get_entries(self, data: dict):
+        return [
+            {
+                'Time': datetime.now(),
+                'Source': self.source,
+                'DetailType': self.name,
+                'Detail': json.dumps({"type": self.name, **data}),
+                'EventBusName': self.event_bus_name,
+            },
+        ]
+
     def apply(self, data: dict):
         client = boto3.client('events', endpoint_url=settings.AWS_EVENTS_URL)
-        client.put_events(
-            Entries=[
-                {
-                    'Time': datetime.now(),
-                    'Source': self.source,
-                    'DetailType': self.name,
-                    'Detail': json.dumps({"type": self.name, **data}),
-                    'EventBusName': self.event_bus_name,
-                },
-            ]
-        )
+        client.put_events(Entries=self.get_entries(data))
+
+
+class TaskPrinter(Task):
+    def apply(self, data: dict):
+        entries = self.get_entries(data)
+        print(f"Put events: {entries=}")

services/backend/restauth/settings.py

@@ -154,3 +154,5 @@
 WORKERS_EVENT_BUS_NAME = env("WORKERS_EVENT_BUS_NAME", default=None)
 
 AWS_EVENTS_URL = env("AWS_EVENTS_URL", default=None)
+
+TASKS_BASE_HANDLER = env("TASKS_BASE_HANDLER", default="common.tasks.Task")