add deployment documentation for Python frontend

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

diff --git a/nominatim/server/falcon/server.py b/nominatim/server/falcon/server.py
index c11cf4a845de734f1f68319990ebb6b179ca40d1..f1030f5c82205c85b798e418f3f740343ce04951 100644 (file)
--- a/nominatim/server/falcon/server.py
+++ b/nominatim/server/falcon/server.py
@@ -9,6 +9,7 @@ Server implementation using the falcon webserver framework.
 """
 from typing import Optional, Mapping, cast, Any
 from pathlib import Path
 """
 from typing import Optional, Mapping, cast, Any
 from pathlib import Path

+import datetime as dt

 
 from falcon.asgi import App, Request, Response
 
 
 from falcon.asgi import App, Request, Response
 


@@ -36,6 +37,17 @@ async def nominatim_error_handler(req: Request, resp: Response, #pylint: disable
     resp.content_type = exception.content_type
 
 
     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.
     """
 class ParamWrapper(api_impl.ASGIAdaptor):
     """ Adaptor class for server glue to Falcon framework.
     """


@@ -59,12 +71,16 @@ class ParamWrapper(api_impl.ASGIAdaptor):
         return HTTPNominatimError(msg, status, self.content_type)
 
 
         return HTTPNominatimError(msg, status, self.content_type)
 
 

-    def create_response(self, status: int, output: str) -> None:
+    def create_response(self, status: int, output: str, num_results: int) -> None:
+        self.response.context.num_results = num_results

         self.response.status = status
         self.response.text = output
         self.response.content_type = self.content_type
 
 
         self.response.status = status
         self.response.text = output
         self.response.content_type = self.content_type
 
 

+    def base_uri(self) -> str:
+        return cast (str, self.request.forwarded_prefix)
+

     def config(self) -> Configuration:
         return self._config
 
     def config(self) -> Configuration:
         return self._config
 


@@ -73,7 +89,8 @@ class EndpointWrapper:
     """ Converter for server glue endpoint functions to Falcon request handlers.
     """
 
     """ Converter for server glue endpoint functions to Falcon request handlers.
     """
 

-    def __init__(self, func: api_impl.EndpointFunc, api: NominatimAPIAsync) -> None:
+    def __init__(self, name: str, func: api_impl.EndpointFunc, api: NominatimAPIAsync) -> None:
+        self.name = name

         self.func = func
         self.api = api
 
         self.func = func
         self.api = api
 


@@ -84,18 +101,60 @@ class EndpointWrapper:
         await self.func(self.api, ParamWrapper(req, resp, self.api.config))
 
 
         await self.func(self.api, ParamWrapper(req, resp, self.api.config))
 
 

+class FileLoggingMiddleware:
+    """ Middleware to log selected requests into a file.
+    """
+
+    def __init__(self, file_name: str):
+        self.fd = open(file_name, 'a', buffering=1, encoding='utf8') # pylint: disable=R1732
+
+
+    async def process_request(self, req: Request, _: Response) -> None:
+        """ Callback before the request starts timing.
+        """
+        req.context.start = dt.datetime.now(tz=dt.timezone.utc)
+
+
+    async def process_response(self, req: Request, resp: Response,
+                               resource: Optional[EndpointWrapper],
+                               req_succeeded: bool) -> None:
+        """ Callback after requests writes to the logfile. It only
+            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'):
+            return
+
+        finish = dt.datetime.now(tz=dt.timezone.utc)
+        duration = (finish - req.context.start).total_seconds()
+        params = req.scope['query_string'].decode('utf8')
+        start = req.context.start.replace(tzinfo=None)\
+                                 .isoformat(sep=' ', timespec='milliseconds')
+
+        self.fd.write(f"[{start}] "
+                      f"{duration:.4f} {getattr(resp.context, 'num_results', 0)} "
+                      f'{resource.name} "{params}"\n')
+
+

 def get_application(project_dir: Path,
                     environ: Optional[Mapping[str, str]] = None) -> App:
     """ Create a Nominatim Falcon ASGI application.
     """
     api = NominatimAPIAsync(project_dir, environ)
 
 def get_application(project_dir: Path,
                     environ: Optional[Mapping[str, str]] = None) -> App:
     """ Create a Nominatim Falcon ASGI application.
     """
     api = NominatimAPIAsync(project_dir, environ)
 

-    app = App(cors_enable=api.config.get_bool('CORS_NOACCESSCONTROL'))
+    middleware: Optional[object] = None
+    log_file = api.config.LOG_FILE
+    if log_file:
+        middleware = 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(HTTPNominatimError, nominatim_error_handler)

+    app.add_error_handler(TimeoutError, timeout_error_handler)

 
     legacy_urls = api.config.get_bool('SERVE_LEGACY_URLS')
     for name, func in api_impl.ROUTES:
 
     legacy_urls = api.config.get_bool('SERVE_LEGACY_URLS')
     for name, func in api_impl.ROUTES:

-        endpoint = EndpointWrapper(func, api)
+        endpoint = EndpointWrapper(name, func, api)

         app.add_route(f"/{name}", endpoint)
         if legacy_urls:
             app.add_route(f"/{name}.php", endpoint)
         app.add_route(f"/{name}", endpoint)
         if legacy_urls:
             app.add_route(f"/{name}.php", endpoint)