Merge 03ca1f0 into dbf81d1

starlette_opentracing/middleware.py

@@ -4,13 +4,29 @@
 from opentracing import InvalidCarrierException, SpanContextCorruptedException
 from opentracing.ext import tags
 from starlette.middleware.base import BaseHTTPMiddleware
+from starlette.requests import Request
 
 
 class StarletteTracingMiddleWare(BaseHTTPMiddleware):
-    def __init__(self, app, tracer):
+    def __init__(self, app, tracer, use_template: bool = False):
         # Todo: add choice between global tracer and tracer that is already configured
         super().__init__(app)
         self._tracer = tracer
+        self.use_template = use_template
+
+    def get_template(self, request: Request) -> str:
+        """Get the template for the route endpoint."""
+        method = request.method
+        urls = [
+            route
+            for route in request.scope["router"].routes
+            if hasattr(route, "endpoint") and
+            "endpoint" in request.scope and
+            route.endpoint == request.scope["endpoint"]
+        ]
+        template = urls[0].path if len(urls) > 0 else "UNKNOWN"
+        method_path = method + " " + template
+        return method_path
 
     async def dispatch(self, request, call_next):
         span_ctx = None
@@ -38,4 +54,8 @@ async def dispatch(self, request, call_next):
             span.set_tag(tags.HTTP_URL, url)
 
             response = await call_next(request)
+
+            if self.use_template:
+                operation_name = self.get_template(request)
+                span.set_operation_name(operation_name)
         return response

tests/test_tracer.py

@@ -55,3 +55,21 @@ def foo(request):
     # Todo: more asserts; still not sure if we should have 3 finished spans in the external tracer
     spans = external_tracer.finished_spans()
     assert len(spans) == 1
+
+
+def test_tracer_uses_path_templates_for_operation_names():
+    app = Starlette()
+    mocked_tracer = MockTracer(scope_manager=ContextVarsScopeManager())
+    app.add_middleware(
+        StarletteTracingMiddleWare, tracer=mocked_tracer, use_template=True
+    )
+
+    @app.route("/foo/{foo_id}")
+    def foo(foo_id: str):
+        return PlainTextResponse(f"Foo: {foo_id}")
+
+    client = TestClient(app)
+    client.get("/foo/MyFoo")
+    spans = mocked_tracer.finished_spans()
+    assert len(spans) == 1
+    assert spans[0].operation_name == "GET /foo/{foo_id}"