[python_lambda] fix issues preventing some tests

Author: florentinl

docs/scenarios/aws_lambda.md

@@ -36,14 +36,28 @@ flowchart TD
     TESTS[Tests Container] -->|Send Requests| LambdaProxy
     LambdaProxy[Lambda Proxy] -->|Send Lambda Event| Application
     subgraph APP[Application Container]
-        Extension[Extension *:8126]
+        socat[socat *:8127] --> Extension
+        Extension[Extension localhost:8126]
         Application[Application *:8080]
     end
     Application --> | Send Traces | APPPROXY
-    APPPROXY[Application Proxy] --> | Send back traces | Extension
+    APPPROXY[Application Proxy] --> | Send back traces | socat
     APPPROXY -->|mitmdump| TESTS
     Extension --> AGENTPROXY
     AGENTPROXY[Agent Proxy] -->|remote request| BACKEND
     AGENTPROXY -->|mitmdump| TESTS
     BACKEND[Datadog] -->|trace API| TESTS
 ```
+
+## Specific considerations for the weblogs
+
+On top of responding to the regular [`/healthcheck`](../weblog/README.md#get-healthcheck) endpoint.
+
+Lambda Weblogs should respond the same JSON dict response to the non HTTP event:
+```json
+{
+    "healthcheck": true
+}
+```
+
+This is because the healthcheck is sent by the Lambda Weblog container itself which has no knowledge of how to serialize it as the event type expected by the weblog.

tests/appsec/test_only_python.py

@@ -12,12 +12,12 @@
 @scenarios.default
 @scenarios.appsec_lambda_default
 @features.language_specifics
-@irrelevant(context.library != "python", reason="specific tests for python tracer")
+@irrelevant(context.library not in ("python", "python_lambda"), reason="specific tests for python tracer")
 class Test_ImportError:
     """Tests to verify that we don't have import errors due to tracer instrumentation."""
 
     @flaky(context.library == "python@3.2.1" and "flask" in context.weblog_variant, reason="APMRP-360")
     def test_circular_import(self):
         """Test to verify that we don't have a circular import in the weblog."""
-        assert context.library == "python"
+        assert context.library in ("python", "python_lambda")
         interfaces.library_stdout.assert_absence("most likely due to a circular import")

utils/_context/_scenarios/__init__.py

@@ -1083,6 +1083,7 @@ class _Scenarios:
     appsec_lambda_default = LambdaScenario(
         "APPSEC_LAMBDA_DEFAULT",
         doc="Default Lambda scenario",
+        scenario_groups=[scenario_groups.appsec],
     )
 
 

utils/_context/_scenarios/aws_lambda.py

@@ -29,7 +29,6 @@ def __init__(
         weblog_volumes: dict[str, dict[str, str]] | None = None,
     ):
         scenario_groups = [
-            all_scenario_groups.appsec,
             all_scenario_groups.tracer_release,
         ] + (scenario_groups or [])
 
@@ -53,7 +52,7 @@ def __init__(
         self.proxy_container.environment.update(
             {
                 "PROXY_TRACING_AGENT_TARGET_HOST": self.lambda_weblog.name,
-                "PROXY_TRACING_AGENT_TARGET_PORT": "8126",
+                "PROXY_TRACING_AGENT_TARGET_PORT": "8127",
             }
         )
 

utils/build/docker/lambda_proxy/main.py

@@ -23,7 +23,12 @@ def invoke_lambda_function():
     This function is used to invoke the Lambda function with the provided event.
     It constructs a v1 event from the Flask request and sends it to the RIE URL.
     """
-    converted_event = construct_v1_event(request, PORT, binary_types=["application/octet-stream"], stage_name="Prod")
+    converted_event = construct_v1_event(
+        request,
+        PORT,
+        binary_types=["application/octet-stream"],
+        stage_name="Prod",
+    )
 
     response = post(
         RIE_URL,
@@ -32,22 +37,33 @@ def invoke_lambda_function():
     )
 
     (status_code, headers, body) = LocalApigwService._parse_v1_payload_format_lambda_output(
-        response.content.decode("utf-8"), binary_types=[], flask_request=request, event_type="Api"
+        response.content.decode("utf-8"),
+        binary_types=[],
+        flask_request=request,
+        event_type="Api",
     )
 
     return app.response_class(response=body, status=status_code, headers=headers)
 
 
-@app.route("/", methods=["GET", "POST", "OPTIONS"])
-@app.route("/finger_print")
-@app.get("/headers")
-@app.get("/healthcheck")
-@app.route("/params/<path>/", methods=["GET", "POST", "OPTIONS"])
-@app.route("/tag_value/<string:tag_value>/<int:status_code>", methods=["GET", "POST", "OPTIONS"])
-@app.get("/users")
-@app.route("/waf", methods=["GET", "POST", "OPTIONS"])
-@app.route("/waf/", methods=["GET", "POST", "OPTIONS"])
-@app.route("/waf/<path:url>", methods=["GET", "POST", "OPTIONS"])
-@app.get("/.git")
-def main(**kwargs):
-    return invoke_lambda_function()
+ROUTES = [
+    ("/", ["GET", "POST", "OPTIONS"]),
+    ("/finger_print", ["GET"]),
+    ("/headers", ["GET"]),
+    ("/healthcheck", ["GET"]),
+    ("/params/<path>/", ["GET", "POST", "OPTIONS"]),
+    ("/tag_value/<tag_value>/<status_code>", ["GET", "POST", "OPTIONS"]),
+    ("/users", ["GET"]),
+    ("/waf", ["GET", "POST", "OPTIONS"]),
+    ("/waf/", ["GET", "POST", "OPTIONS"]),
+    ("/waf/<path>", ["GET", "POST", "OPTIONS"]),
+    ("/.git", ["GET"]),
+]
+
+for endpoint, methods in ROUTES:
+    app.add_url_rule(
+        endpoint,
+        endpoint,
+        lambda **kwargs: invoke_lambda_function(),
+        methods=methods,
+    )

utils/build/docker/python_lambda/apigw-rest.Dockerfile

@@ -1,6 +1,6 @@
 FROM public.ecr.aws/lambda/python:3.13
 
-RUN dnf install -y unzip findutils
+RUN dnf install -y unzip findutils socat
 
 # Add the Datadog Extension
 RUN mkdir -p /opt/extensions

utils/build/docker/python_lambda/function/app.sh

@@ -4,4 +4,6 @@ set -eu
 
 export DD_LAMBDA_HANDLER=handler.lambda_handler
 
+socat TCP-LISTEN:8127,reuseaddr,fork,bind=0.0.0.0 TCP:127.0.0.1:8126 &
+
 exec /lambda-entrypoint.sh datadog_lambda.handler.handler

utils/build/docker/python_lambda/function/handler.py

@@ -32,20 +32,6 @@ def version_info():
     }
 
 
-@app.get("/tag_value/<tag_value>/<status_code>")
-@app.route("/tag_value/<tag_value>/<status_code>", method="OPTIONS")
-def tag_value(tag_value: str, status_code: int):
-    appsec_trace_utils.track_custom_event(
-        tracer, event_name=_TRACK_CUSTOM_APPSEC_EVENT_NAME, metadata={"value": tag_value}
-    )
-    return Response(
-        status_code=status_code,
-        content_type="text/plain",
-        body="Value tagged",
-        headers=app.current_event.query_string_parameters,
-    )
-
-
 @app.get("/")
 @app.post("/")
 @app.route("/", method="OPTIONS")
@@ -83,6 +69,20 @@ def waf_params(path: str = ""):
     )
 
 
+@app.get("/tag_value/<tag_value>/<status_code>")
+@app.route("/tag_value/<tag_value>/<status_code>", method="OPTIONS")
+def tag_value(tag_value: str, status_code: int):
+    appsec_trace_utils.track_custom_event(
+        tracer, event_name=_TRACK_CUSTOM_APPSEC_EVENT_NAME, metadata={"value": tag_value}
+    )
+    return Response(
+        status_code=status_code,
+        content_type="text/plain",
+        body="Value tagged",
+        headers=app.current_event.query_string_parameters,
+    )
+
+
 @app.post("/tag_value/<tag_value>/<status_code>")
 def tag_value_post(tag_value: str, status_code: int):
     appsec_trace_utils.track_custom_event(