+class FileLoggingMiddleware(BaseHTTPMiddleware):
+ """ Middleware to log selected requests into a file.
+ """
+
+ def __init__(self, app: Starlette, file_name: str = ''):
+ super().__init__(app)
+ self.fd = open(file_name, 'a', buffering=1, encoding='utf8') # pylint: disable=R1732
+
+ async def dispatch(self, request: Request,
+ call_next: RequestResponseEndpoint) -> Response:
+ start = dt.datetime.now(tz=dt.timezone.utc)
+ response = await call_next(request)
+
+ if response.status_code != 200:
+ return response
+
+ finish = dt.datetime.now(tz=dt.timezone.utc)
+
+ for endpoint in ('reverse', 'search', 'lookup', 'details'):
+ if request.url.path.startswith('/' + endpoint):
+ qtype = endpoint
+ break
+ else:
+ return response
+
+ duration = (finish - start).total_seconds()
+ params = request.scope['query_string'].decode('utf8')
+
+ self.fd.write(f"[{start.replace(tzinfo=None).isoformat(sep=' ', timespec='milliseconds')}] "
+ f"{duration:.4f} {getattr(request.state, 'num_results', 0)} "
+ f'{qtype} "{params}"\n')
+
+ return response
+
+
+async def timeout_error(request: Request, #pylint: disable=unused-argument
+ _: Exception) -> Response:
+ """ Error handler for query timeouts.
+ """
+ return PlainTextResponse("Query took too long to process.", status_code=503)
+
+