catch special async timeout error in servers

[nominatim.git] / nominatim / server / falcon / server.py

diff --git a/nominatim/server/falcon/server.py b/nominatim/server/falcon/server.py
index e551e54256f531ddc1e101caa2ada639b09b05e4..00036795ae67b80f5c89726559bdd9860abb0dcb 100644 (file)
--- a/nominatim/server/falcon/server.py
+++ b/nominatim/server/falcon/server.py
@@ -7,9 +7,10 @@
 """
 Server implementation using the falcon webserver framework.
 """
-from typing import Optional, Mapping, cast, Any
+from typing import Optional, Mapping, cast, Any, List
 from pathlib import Path
 import datetime as dt
+import asyncio
 
 from falcon.asgi import App, Request, Response
 
@@ -37,6 +38,17 @@ async def nominatim_error_handler(req: Request, resp: Response, #pylint: disable
     resp.content_type = exception.content_type
 
 
+async def timeout_error_handler(req: Request, resp: Response, #pylint: disable=unused-argument
+                                exception: TimeoutError, #pylint: disable=unused-argument
+                                _: Any) -> None:
+    """ Special error handler that passes message and content type as
+        per exception info.
+    """
+    resp.status = 503
+    resp.text = "Query took too long to process."
+    resp.content_type = 'text/plain; charset=utf-8'
+
+
 class ParamWrapper(api_impl.ASGIAdaptor):
     """ Adaptor class for server glue to Falcon framework.
     """
@@ -111,7 +123,7 @@ class FileLoggingMiddleware:
             writes logs for sucessful requests for search, reverse and lookup.
         """
         if not req_succeeded or resource is None or resp.status != 200\
-            or resource.name not in ('reverse', 'search', 'lookup'):
+            or resource.name not in ('reverse', 'search', 'lookup', 'details'):
             return
 
         finish = dt.datetime.now(tz=dt.timezone.utc)
@@ -125,20 +137,36 @@ class FileLoggingMiddleware:
                       f'{resource.name} "{params}"\n')
 
 
+class APIShutdown:
+    """ Middleware that closes any open database connections.
+    """
+
+    def __init__(self, api: NominatimAPIAsync) -> None:
+        self.api = api
+
+    async def process_shutdown(self, *_: Any) -> None:
+        """Process the ASGI lifespan shutdown event.
+        """
+        await self.api.close()
+
+
 def get_application(project_dir: Path,
                     environ: Optional[Mapping[str, str]] = None) -> App:
     """ Create a Nominatim Falcon ASGI application.
     """
     api = NominatimAPIAsync(project_dir, environ)
 
-    middleware: Optional[object] = None
+    middleware: List[object] = [APIShutdown(api)]
     log_file = api.config.LOG_FILE
     if log_file:
-        middleware = FileLoggingMiddleware(log_file)
+        middleware.append(FileLoggingMiddleware(log_file))
 
     app = App(cors_enable=api.config.get_bool('CORS_NOACCESSCONTROL'),
               middleware=middleware)
     app.add_error_handler(HTTPNominatimError, nominatim_error_handler)
+    app.add_error_handler(TimeoutError, timeout_error_handler)
+    # different from TimeoutError in Python <= 3.10
+    app.add_error_handler(asyncio.TimeoutError, timeout_error_handler)
 
     legacy_urls = api.config.get_bool('SERVE_LEGACY_URLS')
     for name, func in api_impl.ROUTES: