feat: add handler wrapper function (#30)

src/routing.py

@@ -2,14 +2,15 @@
 import logging
 from datetime import datetime, timezone
 from http import HTTPStatus
-from typing import Any, Callable, Dict
+from typing import Any, Awaitable, Callable, Dict
 from uuid import uuid4
 
 from fastapi import Request, Response, routing
 
 logger = logging.getLogger(__name__)
 
 Handler = Callable[[Dict[str, Any], Any], Dict[str, Any]]
+Endpoint = Callable[[Request], Awaitable[Response]]
 
 
 class ApiGatewayResponse(Response):
@@ -51,6 +52,17 @@ async def event_builder(request: Request) -> Dict[str, Any]:
  return event
 
 
+def handler(func: Handler) -> Endpoint:
+ async def wrapper(request: Request) -> Response:
+ event = await event_builder(request)
+ result = func(event, None)
+ response = ApiGatewayResponse(result)
+
+ return response
+
+ return wrapper
+
+
 def default_endpoint(request: Request) -> Response:
  logger.error(f"Executing default endpoint: {request.scope}")
 

tests/test_routing.py

@@ -7,6 +7,29 @@
 import routing
 
 
+def build_request():
+ async def receive():
+ return {"type": "http.request", "body": b'{"message": "test"}'}
+
+ scope = {
+ "type": "http",
+ "http_version": "1.1",
+ "root_path": "",
+ "path": "/test",
+ "method": "GET",
+ "query_string": [],
+ "path_params": {},
+ "client": ("127.0.0.1", 80),
+ "app": FastAPI(),
+ "headers": [
+ (b"content-type", b"application/json"),
+ (b"user-agent", b"python/unittest"),
+ ],
+ }
+
+ return Request(scope, receive)
+
+
 class TestAPIRoute(unittest.TestCase):
  def test_default_endpoint(self):
  with self.assertLogs(logger=routing.__name__, level="ERROR") as logs:
@@ -76,25 +99,7 @@ def test_response_creation_fails_when_missing_required_attribute(self):
 
 class TestEventBuilder(unittest.IsolatedAsyncioTestCase):
  async def test_event_builder(self):
- async def receive():
- return {"type": "http.request", "body": b'{"message": "test"}'}
-
- scope = {
- "type": "http",
- "http_version": "1.1",
- "root_path": "",
- "path": "/test",
- "method": "GET",
- "query_string": [],
- "path_params": {},
- "client": ("127.0.0.1", 80),
- "app": FastAPI(),
- "headers": [
- (b"content-type", b"application/json"),
- (b"user-agent", b"python/unittest"),
- ],
- }
- request = Request(scope, receive)
+ request = build_request()
  expected_keys = {
  "body",
  "path",
@@ -110,3 +115,23 @@ async def receive():
 
  self.assertIsInstance(event, dict)
  self.assertEqual(set(event.keys()), expected_keys)
+
+
+class TestHandler(unittest.IsolatedAsyncioTestCase):
+ async def test_handler(self):
+ request = build_request()
+
+ def echo(event, _):
+ return {
+ "statusCode": HTTPStatus.OK.value,
+ "body": event["body"],
+ "headers": event["headers"],
+ }
+
+ endpoint = routing.handler(echo)
+ response = await endpoint(request)
+
+ self.assertIsInstance(response, Response)
+ self.assertEqual(response.status_code, HTTPStatus.OK.value)
+ self.assertEqual(response.body.decode(), '{"message": "test"}')
+ self.assertEqual(response.headers["content-type"], "application/json")