Change failed trace from using 504 to instead use 422

app/routers/contacts.py

@@ -462,7 +462,7 @@ async def request_trace(public_key: str) -> TraceResponse:
         )
 
     if event is None:
-        raise HTTPException(status_code=504, detail="No trace response heard")
+        raise HTTPException(status_code=422, detail="No trace response heard")
 
     trace = event.payload
     path = trace.get("path", [])

app/routers/radio.py

@@ -561,7 +561,7 @@ async def trace_path(request: RadioTraceRequest) -> RadioTraceResponse:
             try:
                 event = await asyncio.wait_for(response_task, timeout=timeout_seconds)
             except TimeoutError as exc:
-                raise HTTPException(status_code=504, detail="No trace response heard") from exc
+                raise HTTPException(status_code=422, detail="No trace response heard") from exc
         finally:
             if not response_task.done():
                 response_task.cancel()
@@ -569,7 +569,7 @@ async def trace_path(request: RadioTraceRequest) -> RadioTraceResponse:
                 await response_task
 
     if event is None:
-        raise HTTPException(status_code=504, detail="No trace response heard")
+        raise HTTPException(status_code=422, detail="No trace response heard")
 
     payload = event.payload if isinstance(event.payload, dict) else {}
     path_len = payload.get("path_len")

tests/test_radio_router.py

@@ -699,7 +699,7 @@ class TestTracePath:
         assert "not a repeater" in exc.value.detail
 
     @pytest.mark.asyncio
-    async def test_returns_504_when_no_trace_response_is_heard(self):
+    async def test_returns_422_when_no_trace_response_is_heard(self):
         mc = _mock_meshcore_with_info()
         repeater = Contact(
             public_key="44" * 32,
@@ -741,7 +741,7 @@ class TestTracePath:
                     )
                 )
 
-        assert exc.value.status_code == 504
+        assert exc.value.status_code == 422
         assert "No trace response heard" in exc.value.detail
 
     @pytest.mark.asyncio

tests/test_repeater_routes.py

@@ -510,7 +510,7 @@ class TestTraceRoute:
         )
 
     @pytest.mark.asyncio
-    async def test_wait_timeout_returns_504(self, test_db):
+    async def test_wait_timeout_returns_422(self, test_db):
         mc = _mock_mc()
         await _insert_contact(KEY_A, name="Client", contact_type=1)
         mc.commands.send_trace = AsyncMock(return_value=_radio_result(EventType.OK))
@@ -524,7 +524,7 @@ class TestTraceRoute:
             with pytest.raises(HTTPException) as exc:
                 await request_trace(KEY_A)
 
-        assert exc.value.status_code == 504
+        assert exc.value.status_code == 422
         mc.commands.send_trace.assert_awaited_once_with(
             path=KEY_A[:8],
             tag=1234,