Prevent AttributeError from being raised when lambda event is a list (#1738)

CHANGELOG.md

@@ -16,6 +16,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Make Django request span attributes available for `start_span`. 
   ([#1730](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/1730))
 
+### Fixed
+
+- Fix `AttributeError` when AWS Lambda handler receives a list event
+  ([#1738](https://github.com/open-telemetry/opentelemetry-python-contrib/pull/1738))
+
 
 ## Version 1.17.0/0.38b0 (2023-03-22)
 

instrumentation/opentelemetry-instrumentation-aws-lambda/src/opentelemetry/instrumentation/aws_lambda/__init__.py

@@ -342,7 +342,9 @@ def _instrument(
             # If the request came from an API Gateway, extract http attributes from the event
             # https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/instrumentation/aws-lambda.md#api-gateway
             # https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/trace/semantic_conventions/http.md#http-server-semantic-conventions
-            if lambda_event and lambda_event.get("requestContext"):
+            if isinstance(lambda_event, dict) and lambda_event.get(
+                "requestContext"
+            ):
                 span.set_attribute(SpanAttributes.FAAS_TRIGGER, "http")
 
                 if lambda_event.get("version") == "2.0":

instrumentation/opentelemetry-instrumentation-aws-lambda/tests/test_aws_lambda_instrumentation_manual.py

@@ -399,6 +399,15 @@ class TestAwsLambdaInstrumentor(TestBase):
             },
         )
 
+    def test_lambda_handles_list_event(self):
+        AwsLambdaInstrumentor().instrument()
+
+        mock_execute_lambda([{"message": "test"}])
+
+        spans = self.memory_exporter.get_finished_spans()
+
+        assert spans
+
     def test_uninstrument(self):
         AwsLambdaInstrumentor().instrument()