feat(appsec): add metric for unsupported lambda event types

Author: florentinl

ddtrace/appsec/_constants.py

@@ -121,6 +121,7 @@ class APPSEC(metaclass=Constant_Class):
     RASP_ERROR: Literal["_dd.appsec.rasp.error"] = "_dd.appsec.rasp.error"
     ERROR_TYPE: Literal["_dd.appsec.error.type"] = "_dd.appsec.error.type"
     ERROR_MESSAGE: Literal["_dd.appsec.error.message"] = "_dd.appsec.error.message"
+    UNSUPPORTED_EVENT_TYPE: Literal["_dd.appsec.unsupported_event_type"] = "_dd.appsec.unsupported_event_type"
 
 
 TELEMETRY_OFF_NAME = "OFF"

ddtrace/appsec/_processor.py

@@ -14,6 +14,9 @@
 from typing import Tuple
 from typing import Union
 
+from ddtrace.ext import SpanTypes
+from ddtrace.internal import core
+
 
 if TYPE_CHECKING:
     import ddtrace.appsec._ddwaf as ddwaf
@@ -181,6 +184,16 @@ def on_span_start(self, span: Span) -> None:
         if span.span_type not in asm_config._asm_processed_span_types:
             return
 
+        if span.span_type == SpanTypes.SERVERLESS:
+            skip_event = core.get_item("asm_skip_next_lambda_event")
+            if skip_event:
+                core.discard_item("asm_skip_next_lambda_event")
+                log.debug(
+                    "appsec: ignoring unsupported lamdba event",
+                )
+                span.set_metric(APPSEC.UNSUPPORTED_EVENT_TYPE, 1.0)
+                return
+
         ctx = self._ddwaf._at_request_start()
         _asm_request_context.start_context(span, ctx.rc_products if ctx is not None else "")
         peer_ip = _asm_request_context.get_ip()