Feature: Include trace flags in spans exported by the OTLPSpanExporter

.changelog/5667.fixed

@@ -0,0 +1 @@
+`opentelemetry-exporter-otlp`: Include trace flags in spans exported by the OTLPSpanExporter

exporter/opentelemetry-exporter-otlp-json-common/src/opentelemetry/exporter/otlp/json/common/_internal/trace_encoder/__init__.py

@@ -84,8 +84,12 @@ def _encode_resource_spans(
     return json_resource_spans
 
 
-def _span_flags(parent_span_context: SpanContext | None) -> int:
-    flags = JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK
+def _span_flags(
+    span_context: SpanContext | None,
+    parent_span_context: SpanContext | None,
+) -> int:
+    flags = int(span_context.trace_flags) if span_context else 0
+    flags |= JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK
     if parent_span_context and parent_span_context.is_remote:
         flags |= JSONSpanFlags.SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK
     return int(flags)
@@ -109,7 +113,7 @@ def _encode_span(sdk_span: ReadableSpan) -> JSONSpan:
         dropped_attributes_count=sdk_span.dropped_attributes,
         dropped_events_count=sdk_span.dropped_events,
         dropped_links_count=sdk_span.dropped_links,
-        flags=_span_flags(sdk_span.parent),
+        flags=_span_flags(span_context, sdk_span.parent),
     )
 
 
@@ -134,7 +138,7 @@ def _encode_links(links: Collection[Link]) -> list[JSONSpan.Link]:
             span_id=_encode_span_id(link.context.span_id),
             attributes=_encode_attributes(link.attributes),
             dropped_attributes_count=link.dropped_attributes,
-            flags=_span_flags(link.context),
+            flags=_span_flags(link.context, link.context),
         )
         for link in links
     ]

exporter/opentelemetry-exporter-otlp-json-common/tests/test_trace_encoder.py

@@ -31,7 +31,7 @@
 from opentelemetry.sdk.resources import Resource
 from opentelemetry.sdk.trace import Event, SpanContext
 from opentelemetry.sdk.util.instrumentation import InstrumentationScope
-from opentelemetry.trace import Link, SpanKind
+from opentelemetry.trace import Link, SpanKind, TraceFlags
 from opentelemetry.trace.span import TraceState
 from opentelemetry.trace.status import Status, StatusCode
 from tests import (
@@ -93,7 +93,12 @@ def test_encode_span_events(self):
         self.assertEqual(encoded.events[0].attributes[0].key, "event_key")
 
     def test_encode_span_links(self):
-        link_ctx = SpanContext(TRACE_ID, 0x2222222222222222, is_remote=False)
+        link_ctx = SpanContext(
+            TRACE_ID,
+            0x2222222222222222,
+            is_remote=False,
+            trace_flags=TraceFlags.SAMPLED,
+        )
         link = Link(context=link_ctx, attributes={"link_key": True})
         span = make_span(links=(link,))
         result = encode_spans([span])
@@ -108,7 +113,7 @@ def test_encode_span_links(self):
         self.assertEqual(encoded.links[0].attributes[0].key, "link_key")
         self.assertEqual(
             encoded.links[0].flags,
-            int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK),
+            int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK | TraceFlags.SAMPLED),
         )
 
     def test_encode_span_status(self):
@@ -141,7 +146,11 @@ def test_encode_span_parent(self):
         )
         self.assertEqual(
             encoded.flags,
-            int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK | JSONSpanFlags.SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK),
+            int(
+                JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK
+                | JSONSpanFlags.SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK
+                | TraceFlags.SAMPLED
+            ),
         )
 
     def test_encode_span_no_parent(self):
@@ -152,7 +161,7 @@ def test_encode_span_no_parent(self):
         self.assertIsNone(encoded.parent_span_id)
         self.assertEqual(
             encoded.flags,
-            int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK),
+            int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK | TraceFlags.SAMPLED),
         )
 
     def test_encode_span_grouping_by_resource(self):
@@ -248,27 +257,46 @@ def test_span_kind_map(self):
     def test_span_flags(self):
         cases = [
             (
-                "remote_parent",
+                "sampled_remote_parent",
+                SpanContext(
+                    TRACE_ID,
+                    0x1110,
+                    is_remote=False,
+                    trace_flags=TraceFlags.SAMPLED,
+                ),
                 SpanContext(TRACE_ID, 0x1111, is_remote=True),
                 int(
                     JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK
                     | JSONSpanFlags.SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK
+                    | TraceFlags.SAMPLED
                 ),
             ),
             (
-                "local_parent",
+                "unsampled_local_parent",
+                SpanContext(
+                    TRACE_ID,
+                    0x2220,
+                    is_remote=False,
+                    trace_flags=TraceFlags.DEFAULT,
+                ),
                 SpanContext(TRACE_ID, 0x2222, is_remote=False),
                 int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK),
             ),
             (
                 "no_parent",
+                SpanContext(
+                    TRACE_ID,
+                    0x3330,
+                    is_remote=False,
+                    trace_flags=TraceFlags.SAMPLED,
+                ),
                 None,
-                int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK),
+                int(JSONSpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK | TraceFlags.SAMPLED),
             ),
         ]
-        for name, context, expected_flags in cases:
+        for name, span_context, parent_context, expected_flags in cases:
             with self.subTest(name=name):
-                self.assertEqual(_span_flags(context), expected_flags)
+                self.assertEqual(_span_flags(span_context, parent_context), expected_flags)
 
     def test_encode_status_translations(self):
         cases = [

exporter/opentelemetry-exporter-otlp-proto-common/src/opentelemetry/exporter/otlp/proto/common/_internal/trace_encoder/__init__.py

@@ -90,8 +90,12 @@ def _encode_resource_spans(
     return pb2_resource_spans
 
 
-def _span_flags(parent_span_context: SpanContext | None) -> int:
-    flags = PB2SpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK
+def _span_flags(
+    span_context: SpanContext | None,
+    parent_span_context: SpanContext | None,
+) -> int:
+    flags = int(span_context.trace_flags) if span_context else 0
+    flags |= PB2SpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK
     if parent_span_context and parent_span_context.is_remote:
         flags |= PB2SpanFlags.SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK
     return flags
@@ -115,7 +119,7 @@ def _encode_span(sdk_span: ReadableSpan) -> PB2SPan:
         dropped_attributes_count=sdk_span.dropped_attributes,
         dropped_events_count=sdk_span.dropped_events,
         dropped_links_count=sdk_span.dropped_links,
-        flags=_span_flags(sdk_span.parent),
+        flags=_span_flags(span_context, sdk_span.parent),
     )
 
 
@@ -146,7 +150,7 @@ def _encode_links(links: Sequence[Link]) -> Sequence[PB2SPan.Link]:
                 span_id=_encode_span_id(link.context.span_id),
                 attributes=_encode_attributes(link.attributes),
                 dropped_attributes_count=link.dropped_attributes,
-                flags=_span_flags(link.context),
+                flags=_span_flags(link.context, link.context),
             )
             pb2_links.append(encoded_link)
     return pb2_links

exporter/opentelemetry-exporter-otlp-proto-common/tests/test_trace_encoder.py

@@ -12,6 +12,7 @@
 from opentelemetry.exporter.otlp.proto.common._internal.trace_encoder import (
     _SPAN_KIND_MAP,
     _encode_status,
+    _span_flags,
 )
 from opentelemetry.exporter.otlp.proto.common.trace_encoder import encode_spans
 from opentelemetry.proto.collector.trace.v1.trace_service_pb2 import (
@@ -30,6 +31,7 @@
 )
 from opentelemetry.proto.trace.v1.trace_pb2 import ScopeSpans as PB2ScopeSpans
 from opentelemetry.proto.trace.v1.trace_pb2 import Span as PB2SPan
+from opentelemetry.proto.trace.v1.trace_pb2 import SpanFlags as PB2SpanFlags
 from opentelemetry.proto.trace.v1.trace_pb2 import Status as PB2Status
 from opentelemetry.sdk.trace import Event as SDKEvent
 from opentelemetry.sdk.trace import Resource as SDKResource
@@ -248,7 +250,7 @@ def get_exhaustive_test_spans(
                                         code=SDKStatusCode.ERROR.value,
                                         message="Example description",
                                     ),
-                                    flags=0x300,
+                                    flags=0x301,
                                 )
                             ],
                         ),
@@ -423,3 +425,48 @@ def test_encode_status_code_translations(self):
                 code=SDKStatusCode.ERROR.value,
             ),
         )
+
+    def test_span_flags(self):
+        trace_id = 0x3E0C63257DE34C926F9EFCD03927272E
+        cases = [
+            (
+                "sampled_remote_parent",
+                SDKSpanContext(
+                    trace_id,
+                    0x1110,
+                    is_remote=False,
+                    trace_flags=SDKTraceFlags.SAMPLED,
+                ),
+                SDKSpanContext(trace_id, 0x1111, is_remote=True),
+                (
+                    PB2SpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK
+                    | PB2SpanFlags.SPAN_FLAGS_CONTEXT_IS_REMOTE_MASK
+                    | SDKTraceFlags.SAMPLED
+                ),
+            ),
+            (
+                "unsampled_local_parent",
+                SDKSpanContext(
+                    trace_id,
+                    0x2220,
+                    is_remote=False,
+                    trace_flags=SDKTraceFlags.DEFAULT,
+                ),
+                SDKSpanContext(trace_id, 0x2222, is_remote=False),
+                PB2SpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK,
+            ),
+            (
+                "no_parent",
+                SDKSpanContext(
+                    trace_id,
+                    0x3330,
+                    is_remote=False,
+                    trace_flags=SDKTraceFlags.SAMPLED,
+                ),
+                None,
+                (PB2SpanFlags.SPAN_FLAGS_CONTEXT_HAS_IS_REMOTE_MASK | SDKTraceFlags.SAMPLED),
+            ),
+        ]
+        for name, span_context, parent_context, expected_flags in cases:
+            with self.subTest(name=name):
+                self.assertEqual(_span_flags(span_context, parent_context), expected_flags)

exporter/opentelemetry-exporter-otlp-proto-grpc/tests/test_otlp_exporter_mixin.py

@@ -59,6 +59,7 @@
     OtelComponentTypeValues,
 )
 from opentelemetry.test.mock_test_classes import IterEntryPoint
+from opentelemetry.trace import TraceFlags
 
 logger = getLogger(__name__)
 
@@ -178,6 +179,7 @@ def setUp(self):
                 trace_state={"a": "b", "c": "d"},
                 span_id=10217189687419569865,
                 trace_id=67545097771067222548457157018666467027,
+                trace_flags=TraceFlags.DEFAULT,
             ),
         )
 

exporter/opentelemetry-exporter-otlp-proto-grpc/tests/test_otlp_trace_exporter.py

@@ -60,6 +60,7 @@
 from opentelemetry.test.spantestutil import (
     get_span_with_dropped_attributes_events_links,
 )
+from opentelemetry.trace import TraceFlags
 
 THIS_DIR = os.path.dirname(__file__)
 
@@ -86,6 +87,7 @@ def setUp(self):
                 trace_state={"a": "b", "c": "d"},
                 span_id=10217189687419569865,
                 trace_id=67545097771067222548457157018666467027,
+                trace_flags=TraceFlags.DEFAULT,
             ),
             resource=SDKResource({"a": 1, "b": False}),
             parent=Mock(span_id=12345),
@@ -96,6 +98,7 @@ def setUp(self):
                     **{
                         "context.trace_id": 1,
                         "context.span_id": 2,
+                        "context.trace_flags": TraceFlags.DEFAULT,
                         "attributes": BoundedAttributes(attributes={"a": 1, "b": False}),
                         "dropped_attributes": 0,
                         "kind": OTLPSpan.SpanKind.SPAN_KIND_INTERNAL,  # pylint: disable=no-member
@@ -111,6 +114,7 @@ def setUp(self):
                 trace_state={"a": "b", "c": "d"},
                 span_id=10217189687419569865,
                 trace_id=67545097771067222548457157018666467027,
+                trace_flags=TraceFlags.DEFAULT,
             ),
             resource=SDKResource({"a": 2, "b": False}),
             parent=Mock(span_id=12345),
@@ -123,6 +127,7 @@ def setUp(self):
                 trace_state={"a": "b", "c": "d"},
                 span_id=10217189687419569865,
                 trace_id=67545097771067222548457157018666467027,
+                trace_flags=TraceFlags.DEFAULT,
             ),
             resource=SDKResource({"a": 1, "b": False}),
             parent=Mock(span_id=12345),
@@ -678,6 +683,7 @@ def _create_span_with_status(status: SDKStatus):
             trace_state={"a": "b", "c": "d"},
             span_id=10217189687419569865,
             trace_id=67545097771067222548457157018666467027,
+            trace_flags=TraceFlags.DEFAULT,
         ),
         parent=Mock(span_id=12345),
         instrumentation_scope=InstrumentationScope(name="name", version="version"),