perf: Make async the Event Grid events

main.py

@@ -8,7 +8,16 @@
 
 
 # General imports
-from typing import Any, Callable, Coroutine, Generator, List, Optional, Tuple, Type
+from typing import (
+    Any,
+    Callable,
+    Coroutine,
+    Generator,
+    List,
+    Optional,
+    Tuple,
+    Type,
+)
 from azure.communication.callautomation import (
     CallAutomationClient,
     CallConnectionClient,
@@ -27,7 +36,7 @@
 from azure.eventgrid import EventGridEvent, SystemEventNames
 from azure.identity import DefaultAzureCredential
 from enum import Enum
-from fastapi import FastAPI, status, Request, HTTPException, BackgroundTasks
+from fastapi import FastAPI, status, Request, HTTPException, BackgroundTasks, Response
 from fastapi.responses import JSONResponse, HTMLResponse
 from helpers.config_models.database import ModeEnum as DatabaseMode
 from helpers.logging import build_logger
@@ -220,46 +229,55 @@ async def call_initiate_get(phone_number: str) -> None:
     description="Handle incoming call from a Azure Event Grid event originating from Azure Communication Services.",
 )
 async def call_inbound_post(request: Request):
-    for event_dict in await request.json():
-        event = EventGridEvent.from_dict(event_dict)
-        event_type = event.event_type
-
-        _logger.debug(f"Call inbound event {event_type} with data {event.data}")
-
-        if event_type == SystemEventNames.EventGridSubscriptionValidationEventName:
-            validation_code = event.data["validationCode"]
-            _logger.info(f"Validating Event Grid subscription ({validation_code})")
-            return JSONResponse(
-                content={"validationResponse": event.data["validationCode"]},
-                status_code=status.HTTP_200_OK,
-            )
+    responses = await asyncio.gather(
+        *[call_inbound_worker(event_dict) for event_dict in await request.json()]
+    )
+    for response in responses:
+        if response:
+            return response
+    return Response(status_code=status.HTTP_204_NO_CONTENT)
 
-        elif event_type == SystemEventNames.AcsIncomingCallEventName:
-            if event.data["from"]["kind"] == "phoneNumber":
-                phone_number = event.data["from"]["phoneNumber"]["value"]
-            else:
-                phone_number = event.data["from"]["rawId"]
 
-            _logger.debug(f"Incoming call handler caller ID: {phone_number}")
-            call_context = event.data["incomingCallContext"]
+async def call_inbound_worker(event_dict: dict[str, Any]) -> Optional[JSONResponse]:
+    event = EventGridEvent.from_dict(event_dict)
+    event_type = event.event_type
 
-            try:
-                answer_call_result = call_automation_client.answer_call(
-                    callback_url=await callback_url(phone_number),
-                    cognitive_services_endpoint=CONFIG.cognitive_service.endpoint,
-                    incoming_call_context=call_context,
-                )
-                _logger.info(
-                    f"Answered call with {phone_number} ({answer_call_result.call_connection_id})"
-                )
-            except HttpResponseError as e:
-                if (
-                    "lifetime validation of the signed http request failed"
-                    in e.message.lower()
-                ):
-                    _logger.debug("Old call event received, ignoring")
-                else:
-                    raise e
+    _logger.debug(f"Call inbound event {event_type} with data {event.data}")
+
+    if event_type == SystemEventNames.EventGridSubscriptionValidationEventName:
+        validation_code = event.data["validationCode"]
+        _logger.info(f"Validating Event Grid subscription ({validation_code})")
+        return JSONResponse(
+            content={"validationResponse": event.data["validationCode"]},
+            status_code=status.HTTP_200_OK,
+        )
+
+    elif event_type == SystemEventNames.AcsIncomingCallEventName:
+        if event.data["from"]["kind"] == "phoneNumber":
+            phone_number = event.data["from"]["phoneNumber"]["value"]
+        else:
+            phone_number = event.data["from"]["rawId"]
+
+        _logger.debug(f"Incoming call handler caller ID: {phone_number}")
+        call_context = event.data["incomingCallContext"]
+
+        try:
+            answer_call_result = call_automation_client.answer_call(
+                callback_url=await callback_url(phone_number),
+                cognitive_services_endpoint=CONFIG.cognitive_service.endpoint,
+                incoming_call_context=call_context,
+            )
+            _logger.info(
+                f"Answered call with {phone_number} ({answer_call_result.call_connection_id})"
+            )
+        except HttpResponseError as e:
+            if (
+                "lifetime validation of the signed http request failed"
+                in e.message.lower()
+            ):
+                _logger.debug("Old call event received, ignoring")
+            else:
+                raise e
 
 
 @api.post(