Align tracing with .NET SDK schema and conventions

- Tracer name: 'Microsoft.DurableTask' (matching .NET ActivitySource)
- Span kinds: Server for worker execution (matching .NET)
- Span naming: 'orchestration:<name>' and 'activity:<name>' (not instanceId)
- Add 'durabletask.type' attribute on all spans (matching .NET Schema.cs)
- Use shared constants for attribute keys and type values
- Extract orchestration name from ExecutionStartedEvent for span names

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: torosent

client/src/main/java/com/microsoft/durabletask/DurableTaskGrpcWorker.java

@@ -176,21 +176,27 @@ public void startAndBlock() {
                         // TODO: Run this on a worker pool thread: https://www.baeldung.com/thread-pool-java-and-guava
                         // TODO: Error handling
                         if (!versioningFailed) {
-                            // Extract trace context from ExecutionStartedEvent in the history
-                            TraceContext orchTraceCtx = Stream.concat(
+                            // Extract ExecutionStartedEvent for trace context and orchestration name
+                            ExecutionStartedEvent startedEvent = Stream.concat(
                                     orchestratorRequest.getPastEventsList().stream(),
                                     orchestratorRequest.getNewEventsList().stream())
                                 .filter(event -> event.getEventTypeCase() == HistoryEvent.EventTypeCase.EXECUTIONSTARTED)
-                                .filter(event -> event.getExecutionStarted().hasParentTraceContext())
-                                .map(event -> event.getExecutionStarted().getParentTraceContext())
+                                .map(HistoryEvent::getExecutionStarted)
                                 .findFirst()
                                 .orElse(null);
+
+                            TraceContext orchTraceCtx = (startedEvent != null && startedEvent.hasParentTraceContext())
+                                    ? startedEvent.getParentTraceContext() : null;
+                            String orchName = startedEvent != null ? startedEvent.getName() : "";
+
                             Map<String, String> orchSpanAttrs = new HashMap<>();
-                            orchSpanAttrs.put("durabletask.task.instance_id", orchestratorRequest.getInstanceId());
+                            orchSpanAttrs.put(TracingHelper.ATTR_TYPE, TracingHelper.TYPE_ORCHESTRATION);
+                            orchSpanAttrs.put(TracingHelper.ATTR_TASK_NAME, orchName);
+                            orchSpanAttrs.put(TracingHelper.ATTR_INSTANCE_ID, orchestratorRequest.getInstanceId());
                             Span orchestrationSpan = TracingHelper.startSpan(
-                                    "orchestration:" + orchestratorRequest.getInstanceId(),
+                                    TracingHelper.TYPE_ORCHESTRATION + ":" + orchName,
                                     orchTraceCtx,
-                                    SpanKind.INTERNAL,
+                                    SpanKind.SERVER,
                                     orchSpanAttrs);
                             Scope orchestrationScope = orchestrationSpan.makeCurrent();
 
@@ -254,13 +260,14 @@ public void startAndBlock() {
                         TraceContext activityTraceCtx = activityRequest.hasParentTraceContext()
                                 ? activityRequest.getParentTraceContext() : null;
                         Map<String, String> spanAttributes = new HashMap<>();
-                        spanAttributes.put("durabletask.task.instance_id", activityInstanceId);
-                        spanAttributes.put("durabletask.task.name", activityRequest.getName());
-                        spanAttributes.put("durabletask.task.task_id", String.valueOf(activityRequest.getTaskId()));
+                        spanAttributes.put(TracingHelper.ATTR_TYPE, TracingHelper.TYPE_ACTIVITY);
+                        spanAttributes.put(TracingHelper.ATTR_TASK_NAME, activityRequest.getName());
+                        spanAttributes.put(TracingHelper.ATTR_INSTANCE_ID, activityInstanceId);
+                        spanAttributes.put(TracingHelper.ATTR_TASK_ID, String.valueOf(activityRequest.getTaskId()));
                         Span activitySpan = TracingHelper.startSpan(
-                                "activity:" + activityRequest.getName(),
+                                TracingHelper.TYPE_ACTIVITY + ":" + activityRequest.getName(),
                                 activityTraceCtx,
-                                SpanKind.INTERNAL,
+                                SpanKind.SERVER,
                                 spanAttributes);
                         Scope activityScope = activitySpan.makeCurrent();
 

client/src/main/java/com/microsoft/durabletask/OrchestrationRunner.java

@@ -151,21 +151,27 @@ public TaskOrchestration create() {
                 logger,
                 versioningOptions);
 
-        // Extract trace context from ExecutionStartedEvent in the history
-        OrchestratorService.TraceContext orchTraceCtx = java.util.stream.Stream.concat(
+        // Extract ExecutionStartedEvent for trace context and orchestration name
+        OrchestratorService.ExecutionStartedEvent startedEvent = java.util.stream.Stream.concat(
                 orchestratorRequest.getPastEventsList().stream(),
                 orchestratorRequest.getNewEventsList().stream())
             .filter(event -> event.getEventTypeCase() == OrchestratorService.HistoryEvent.EventTypeCase.EXECUTIONSTARTED)
-            .filter(event -> event.getExecutionStarted().hasParentTraceContext())
-            .map(event -> event.getExecutionStarted().getParentTraceContext())
+            .map(OrchestratorService.HistoryEvent::getExecutionStarted)
             .findFirst()
             .orElse(null);
+
+        OrchestratorService.TraceContext orchTraceCtx = (startedEvent != null && startedEvent.hasParentTraceContext())
+                ? startedEvent.getParentTraceContext() : null;
+        String orchName = startedEvent != null ? startedEvent.getName() : "";
+
         Map<String, String> orchSpanAttrs = new HashMap<>();
-        orchSpanAttrs.put("durabletask.task.instance_id", orchestratorRequest.getInstanceId());
+        orchSpanAttrs.put(TracingHelper.ATTR_TYPE, TracingHelper.TYPE_ORCHESTRATION);
+        orchSpanAttrs.put(TracingHelper.ATTR_TASK_NAME, orchName);
+        orchSpanAttrs.put(TracingHelper.ATTR_INSTANCE_ID, orchestratorRequest.getInstanceId());
         Span orchestrationSpan = TracingHelper.startSpan(
-                "orchestration:" + orchestratorRequest.getInstanceId(),
+                TracingHelper.TYPE_ORCHESTRATION + ":" + orchName,
                 orchTraceCtx,
-                SpanKind.INTERNAL,
+                SpanKind.SERVER,
                 orchSpanAttrs);
         Scope orchestrationScope = orchestrationSpan.makeCurrent();
 

client/src/main/java/com/microsoft/durabletask/TracingHelper.java

@@ -32,7 +32,18 @@
  */
 final class TracingHelper {
 
-    private static final String TRACER_NAME = "durabletask";
+    private static final String TRACER_NAME = "Microsoft.DurableTask";
+
+    // Span type constants matching .NET SDK schema
+    static final String TYPE_ORCHESTRATION = "orchestration";
+    static final String TYPE_ACTIVITY = "activity";
+    static final String TYPE_CREATE_ORCHESTRATION = "create_orchestration";
+
+    // Attribute keys matching .NET SDK schema
+    static final String ATTR_TYPE = "durabletask.type";
+    static final String ATTR_TASK_NAME = "durabletask.task.name";
+    static final String ATTR_INSTANCE_ID = "durabletask.task.instance_id";
+    static final String ATTR_TASK_ID = "durabletask.task.task_id";
 
     private TracingHelper() {
         // Static utility class

client/src/test/java/com/microsoft/durabletask/TracingHelperTest.java

@@ -126,21 +126,25 @@ void extractTraceContext_withTraceState_preservesState() {
     @Test
     void startSpan_createsSpanWithAttributes() {
         Map<String, String> attrs = new HashMap<>();
-        attrs.put("durabletask.task.name", "test-activity");
-        attrs.put("durabletask.task.instance_id", "abc123");
+        attrs.put(TracingHelper.ATTR_TYPE, TracingHelper.TYPE_ACTIVITY);
+        attrs.put(TracingHelper.ATTR_TASK_NAME, "test-activity");
+        attrs.put(TracingHelper.ATTR_INSTANCE_ID, "abc123");
 
-        Span span = TracingHelper.startSpan("activity:test-activity", null, SpanKind.INTERNAL, attrs);
+        Span span = TracingHelper.startSpan("activity:test-activity", null, SpanKind.SERVER, attrs);
         assertNotNull(span);
         span.end();
 
         List<SpanData> spans = spanExporter.getFinishedSpanItems();
         assertEquals(1, spans.size());
         SpanData spanData = spans.get(0);
         assertEquals("activity:test-activity", spanData.getName());
+        assertEquals(io.opentelemetry.api.trace.SpanKind.SERVER, spanData.getKind());
         assertEquals("test-activity", spanData.getAttributes().get(
                 io.opentelemetry.api.common.AttributeKey.stringKey("durabletask.task.name")));
         assertEquals("abc123", spanData.getAttributes().get(
                 io.opentelemetry.api.common.AttributeKey.stringKey("durabletask.task.instance_id")));
+        assertEquals("activity", spanData.getAttributes().get(
+                io.opentelemetry.api.common.AttributeKey.stringKey("durabletask.type")));
     }
 
     @Test