[feat] add fastapi adapter

adapter/http/fastapi/middleware.py

@@ -0,0 +1,69 @@
+from time import perf_counter
+
+from adapter.http.fastapi.dependencies import get_container
+from fastapi import FastAPI, Request, Response
+
+REQUEST_COUNT = 'http.server.request.count'
+REQUEST_DURATION = 'http.server.request.duration'
+
+
+def register_middleware(app: FastAPI) -> None:
+    @app.middleware('http')
+    async def request_logging_middleware(
+        request: Request,
+        call_next,
+    ) -> Response:
+        start = perf_counter()
+        status_code = 500
+
+        try:
+            response = await call_next(request)
+            status_code = response.status_code
+            return response
+        finally:
+            duration_ms = (perf_counter() - start) * 1000
+            container = get_container(request)
+            container.observability.logger.info(
+                'http_request',
+                attrs={
+                    'http.method': request.method,
+                    'http.path': request.url.path,
+                    'http.status_code': status_code,
+                    'http.duration_ms': duration_ms,
+                },
+            )
+
+    @app.middleware('http')
+    async def metrics_middleware(
+        request: Request,
+        call_next,
+    ) -> Response:
+        start = perf_counter()
+        status_code = 500
+
+        try:
+            response = await call_next(request)
+            status_code = response.status_code
+            return response
+        finally:
+            duration_ms = (perf_counter() - start) * 1000
+            container = get_container(request)
+            attrs: dict[str, str | int] = {
+                'http.method': request.method,
+                'http.path': _metric_path(request),
+                'http.status_code': status_code,
+            }
+            container.observability.metrics.increment(REQUEST_COUNT, attrs=attrs)
+            container.observability.metrics.record(
+                REQUEST_DURATION,
+                duration_ms,
+                attrs=attrs,
+            )
+
+
+def _metric_path(request: Request) -> str:
+    route = request.scope.get('route')
+    path = getattr(route, 'path', None)
+    if isinstance(path, str) and path:
+        return path
+    return 'unmatched'