add header parameters to FastAPIInstrumentor().instrument_app

Author: samuelcolvin

instrumentation/opentelemetry-instrumentation-fastapi/src/opentelemetry/instrumentation/fastapi/__init__.py

@@ -76,7 +76,7 @@ def client_response_hook(span: Span, message: dict):
         if span and span.is_recording():
             span.set_attribute("custom_user_attribute_from_response_hook", "some-value")
 
-   FastAPIInstrumentor().instrument(server_request_hook=server_request_hook, client_request_hook=client_request_hook, client_response_hook=client_response_hook)
+   FastAPIInstrumentor().instrument_app(server_request_hook=server_request_hook, client_request_hook=client_request_hook, client_response_hook=client_response_hook)
 
 Capture HTTP request and response headers
 *****************************************
@@ -86,9 +86,10 @@ def client_response_hook(span: Span, message: dict):
 Request headers
 ***************
 To capture HTTP request headers as span attributes, set the environment variable
-``OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST`` to a comma delimited list of HTTP header names.
+``OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST`` to a comma delimited list of HTTP header names,
+or pass the ``http_capture_headers_server_request`` keyword argument to the ``instrument_app`` method.
 
-For example,
+For example using the environment variable,
 ::
 
     export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_REQUEST="content-type,custom_request_header"
@@ -120,9 +121,10 @@ def client_response_hook(span: Span, message: dict):
 Response headers
 ****************
 To capture HTTP response headers as span attributes, set the environment variable
-``OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_RESPONSE`` to a comma delimited list of HTTP header names.
+``OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_RESPONSE`` to a comma delimited list of HTTP header names,
+or pass the ``http_capture_headers_server_response`` keyword argument to the ``instrument_app`` method.
 
-For example,
+For example using the environment variable,
 ::
 
     export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SERVER_RESPONSE="content-type,custom_response_header"
@@ -155,10 +157,12 @@ def client_response_hook(span: Span, message: dict):
 ******************
 In order to prevent storing sensitive data such as personally identifiable information (PII), session keys, passwords,
 etc, set the environment variable ``OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SANITIZE_FIELDS``
-to a comma delimited list of HTTP header names to be sanitized.  Regexes may be used, and all header names will be
-matched in a case-insensitive manner.
+to a comma delimited list of HTTP header names to be sanitized, or pass the ``http_capture_headers_sanitize_fields``
+keyword argument to the ``instrument_app`` method.
 
-For example,
+Regexes may be used, and all header names will be matched in a case-insensitive manner.
+
+For example using the environment variable,
 ::
 
     export OTEL_INSTRUMENTATION_HTTP_CAPTURE_HEADERS_SANITIZE_FIELDS=".*session.*,set-cookie"
@@ -212,6 +216,9 @@ def instrument_app(
         tracer_provider=None,
         meter_provider=None,
         excluded_urls=None,
+        http_capture_headers_server_request: list[str] | None = None,
+        http_capture_headers_server_response: list[str] | None = None,
+        http_capture_headers_sanitize_fields: list[str] | None = None,
     ):
         """Instrument an uninstrumented FastAPI application."""
         if not hasattr(app, "_is_instrumented_by_opentelemetry"):
@@ -238,6 +245,9 @@ def instrument_app(
                 client_response_hook=client_response_hook,
                 tracer_provider=tracer_provider,
                 meter=meter,
+                http_capture_headers_server_request=http_capture_headers_server_request,
+                http_capture_headers_server_response=http_capture_headers_server_response,
+                http_capture_headers_sanitize_fields=http_capture_headers_sanitize_fields,
             )
             app._is_instrumented_by_opentelemetry = True
             if app not in _InstrumentedFastAPI._instrumented_fastapi_apps:

instrumentation/opentelemetry-instrumentation-fastapi/tests/test_fastapi_instrumentation.py

@@ -279,7 +279,7 @@ def test_basic_post_request_metric_success(self):
                 if isinstance(point, NumberDataPoint):
                     self.assertEqual(point.value, 0)
 
-    def test_metric_uninstruemnt_app(self):
+    def test_metric_uninstrument_app(self):
         self._client.get("/foobar")
         self._instrumentor.uninstrument_app(self._app)
         self._client.get("/foobar")
@@ -693,6 +693,82 @@ def test_http_custom_response_headers_not_in_span_attributes(self):
             self.assertNotIn(key, server_span.attributes)
 
 
+class TestHTTPAppWithCustomHeadersParameters(TestBase):
+    """Minimal tests here since the behavior of this logic is tested above and in the ASGI tests."""
+    def setUp(self):
+        super().setUp()
+        self.app = self._create_app()
+        otel_fastapi.FastAPIInstrumentor().instrument_app(
+            self.app,
+            http_capture_headers_server_request=["a.*", "b.*"],
+            http_capture_headers_server_response=["c.*", "d.*"],
+            http_capture_headers_sanitize_fields=[".*secret.*"]
+        )
+        self.client = TestClient(self.app)
+
+    def tearDown(self) -> None:
+        super().tearDown()
+        with self.disable_logging():
+            otel_fastapi.FastAPIInstrumentor().uninstrument_app(self.app)
+
+    @staticmethod
+    def _create_app():
+        app = fastapi.FastAPI()
+
+        @app.get("/foobar")
+        async def _():
+            headers = {
+                "carrot": "bar",
+                "date-secret": "yellow",
+                "egg": "ham",
+            }
+            content = {"message": "hello world"}
+            return JSONResponse(content=content, headers=headers)
+
+        return app
+
+    def test_http_custom_request_headers_in_span_attributes(self):
+        resp = self.client.get("/foobar", headers={
+            "apple": "red", "banana-secret": "yellow", "fig": "green"
+        })
+        self.assertEqual(200, resp.status_code)
+        span_list = self.memory_exporter.get_finished_spans()
+        self.assertEqual(len(span_list), 3)
+
+        server_span = [
+            span for span in span_list if span.kind == trace.SpanKind.SERVER
+        ][0]
+
+        from pprint import pprint
+        pprint(server_span)
+        expected = {
+            # apple should be included because it starts with a
+            "http.request.header.apple": ("red",),
+            # same with banana because it starts with b,
+            # redacted because it contains "secret"
+            "http.request.header.banana_secret": ("[REDACTED]",),
+        }
+        self.assertSpanHasAttributes(server_span, expected)
+        self.assertNotIn("http.request.header.fig", server_span.attributes)
+
+    def test_http_custom_response_headers_in_span_attributes(self):
+        resp = self.client.get("/foobar")
+        self.assertEqual(200, resp.status_code)
+        span_list = self.memory_exporter.get_finished_spans()
+        self.assertEqual(len(span_list), 3)
+
+        server_span = [
+            span for span in span_list if span.kind == trace.SpanKind.SERVER
+        ][0]
+
+        expected = {
+            "http.response.header.carrot": ("bar",),
+            "http.response.header.date_secret": ("[REDACTED]",),
+        }
+        self.assertSpanHasAttributes(server_span, expected)
+        self.assertNotIn("http.response.header.egg", server_span.attributes)
+
+
 @patch.dict(
     "os.environ",
     {