feat(appsec): skip processing spans for events that are not http requests (#627)

Author: florentinl

datadog_lambda/asm.py

@@ -44,6 +44,16 @@ def _merge_single_and_multi_value_headers(
     return _to_single_value_headers(merged_headers)
 
 
+def asm_set_context(event_source: _EventSource):
+    """Add asm specific items to the ExecutionContext.
+
+    This allows the AppSecSpanProcessor to know information about the event
+    at the moment the span is created and skip it when not relevant.
+    """
+    if event_source.event_type not in _http_event_types:
+        core.set_item("appsec_skip_next_lambda_event", True)
+
+
 def asm_start_request(
     span: Span,
     event: Dict[str, Any],

datadog_lambda/wrapper.py

@@ -9,7 +9,7 @@
 from importlib import import_module
 from time import time_ns
 
-from datadog_lambda.asm import asm_start_response, asm_start_request
+from datadog_lambda.asm import asm_set_context, asm_start_response, asm_start_request
 from datadog_lambda.dsm import set_dsm_context
 from datadog_lambda.extension import should_use_extension, flush_extension
 from datadog_lambda.cold_start import (
@@ -239,6 +239,10 @@ def _before(self, event, context):
                     )
                 if config.data_streams_enabled:
                     set_dsm_context(event, event_source)
+
+                if config.appsec_enabled:
+                    asm_set_context(event_source)
+
                 self.span = create_function_execution_span(
                     context=context,
                     function_name=config.function_name,