propagate Lambda span attribute cloud.resource_id to child spans (#284)

*Issue #, if available:*

AppSignals lambda dependency metrics don't show Lambda Alias correctly

*Description of changes:*
Propagate span attribute cloud.resource_id if there is.


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Author: wangzlei

aws-opentelemetry-distro/src/amazon/opentelemetry/distro/_aws_span_processing_util.py

@@ -52,7 +52,7 @@ def get_ingress_operation(__, span: ReadableSpan) -> str:
     """
     operation: str = span.name
     if _AWS_LAMBDA_FUNCTION_NAME in os.environ:
-        operation = os.environ.get(_AWS_LAMBDA_FUNCTION_NAME) + "/Handler"
+        operation = os.environ.get(_AWS_LAMBDA_FUNCTION_NAME) + "/FunctionHandler"
     elif should_use_internal_operation(span):
         operation = INTERNAL_OPERATION
     elif not _is_valid_operation(span, operation):

aws-opentelemetry-distro/src/amazon/opentelemetry/distro/attribute_propagating_span_processor.py

@@ -8,6 +8,7 @@
 from amazon.opentelemetry.distro._aws_span_processing_util import is_aws_sdk_span, is_local_root
 from opentelemetry.context import Context
 from opentelemetry.sdk.trace import ReadableSpan, Span, SpanProcessor
+from opentelemetry.semconv.trace import SpanAttributes
 from opentelemetry.trace import SpanKind
 from opentelemetry.trace.propagation import get_current_span
 
@@ -62,6 +63,12 @@ def on_start(self, span: Span, parent_context: Optional[Context] = None) -> None
             if _is_consumer_kind(span) and _is_consumer_kind(parent_span):
                 span.set_attribute(AWS_CONSUMER_PARENT_SPAN_KIND, parent_span.kind.name)
 
+            # Propagate span attribute cloud.resource_id for extracting lambda alias for dependency metrics.
+            parent_resource_id = parent_span.attributes.get(SpanAttributes.CLOUD_RESOURCE_ID)
+            current_resource_id = span.attributes.get(SpanAttributes.CLOUD_RESOURCE_ID)
+            if current_resource_id is None and parent_resource_id is not None:
+                span.set_attribute(SpanAttributes.CLOUD_RESOURCE_ID, parent_resource_id)
+
         propagation_data: str = None
         if is_local_root(span):
             if not _is_server_kind(span):

aws-opentelemetry-distro/tests/amazon/opentelemetry/distro/test_attribute_propagating_span_processor.py

@@ -195,3 +195,26 @@ def _validate_span_attributes_inheritance(
             self.assertEqual(propagation_value2, leaf_span.attributes.get(_TEST_KEY_2))
         else:
             self.assertIsNone(leaf_span.attributes.get(_TEST_KEY_2))
+
+    def test_attributes_propagation_cloud_resource_id(self):
+        cloud_resource_id = "arn:x1"
+        grand_parent_span: Span = self.tracer.start_span(
+            name="grandparent", kind=SpanKind.INTERNAL, attributes={_TEST_KEY_1: "testValue1"}
+        )
+        parent_span: Span = self.tracer.start_span(
+            name="parent",
+            kind=SpanKind.SERVER,
+            attributes={_TEST_KEY_2: "testValue2", SpanAttributes.CLOUD_RESOURCE_ID: cloud_resource_id},
+            context=set_span_in_context(grand_parent_span),
+        )
+        child_span: Span = self.tracer.start_span(
+            name="child", kind=SpanKind.INTERNAL, context=set_span_in_context(parent_span)
+        )
+        grand_child_span: Span = self.tracer.start_span(
+            name="child", kind=SpanKind.CLIENT, context=set_span_in_context(child_span)
+        )
+
+        self.assertIsNone(grand_parent_span.attributes.get(SpanAttributes.CLOUD_RESOURCE_ID))
+        self.assertIsNotNone(parent_span.attributes.get(SpanAttributes.CLOUD_RESOURCE_ID))
+        self.assertEqual(child_span.attributes.get(SpanAttributes.CLOUD_RESOURCE_ID), cloud_resource_id)
+        self.assertEqual(grand_child_span.attributes.get(SpanAttributes.CLOUD_RESOURCE_ID), cloud_resource_id)

aws-opentelemetry-distro/tests/amazon/opentelemetry/distro/test_aws_span_processing_util.py

@@ -62,7 +62,7 @@ def test_get_ingress_operation_in_lambda(self):
         self.span_data_mock.name = valid_name
         self.span_data_mock.kind = SpanKind.SERVER
         actual_operation: str = get_ingress_operation(self, self.span_data_mock)
-        self.assertEqual(actual_operation, "MyLambda/Handler")
+        self.assertEqual(actual_operation, "MyLambda/FunctionHandler")
 
     def test_get_ingress_operation_http_method_name_and_no_fallback(self):
         invalid_name: str = "GET"