Span is not created for non json metadata

Author: w1am

db-client-java/src/main/java/com/eventstore/dbclient/ClientTelemetry.java

@@ -77,14 +77,18 @@ private static SpanContext tryExtractTracingContext(byte[] userMetadataBytes) {
             if (!TraceId.isValid(traceId) || !SpanId.isValid(spanId))
                 return null;
 
-            return SpanContext.createFromRemoteParent(traceId, spanId, TraceFlags.getSampled(), TraceState.getDefault());
+            return SpanContext.createFromRemoteParent(traceId, spanId, TraceFlags.getSampled(),
+                    TraceState.getDefault());
         } catch (Throwable t) {
             return null;
         }
     }
 
-    static CompletableFuture<WriteResult> traceAppend(BiFunction<ManagedChannel, List<EventData>, CompletableFuture<WriteResult>> appendOperation, ManagedChannel channel,
-                                                      List<EventData> events, String streamId, EventStoreDBClientSettings settings, UserCredentials optionalCallCredentials) {
+    static CompletableFuture<WriteResult> traceAppend(
+            BiFunction<ManagedChannel, List<EventData>, CompletableFuture<WriteResult>> appendOperation,
+            ManagedChannel channel,
+            List<EventData> events, String streamId, EventStoreDBClientSettings settings,
+            UserCredentials optionalCallCredentials) {
         Span span = createSpan(
                 ClientTelemetryConstants.Operations.APPEND,
                 SpanKind.CLIENT,
@@ -115,9 +119,13 @@ static CompletableFuture<WriteResult> traceAppend(BiFunction<ManagedChannel, Lis
         }
     }
 
-    static void traceSubscribe(Runnable tracedOperation, String subscriptionId, ManagedChannel channel, EventStoreDBClientSettings settings,
+    static void traceSubscribe(Runnable tracedOperation, String subscriptionId, ManagedChannel channel,
+                               EventStoreDBClientSettings settings,
                                UserCredentials optionalCallCredentials, RecordedEvent event) {
         SpanContext remoteParentContext = tryExtractTracingContext(event.getUserMetadata());
+
+        if (remoteParentContext == null) return;
+
         Span span = createSpan(
                 ClientTelemetryConstants.Operations.SUBSCRIBE,
                 SpanKind.CONSUMER,
@@ -145,7 +153,8 @@ static void traceSubscribe(Runnable tracedOperation, String subscriptionId, Mana
         }
     }
 
-    static Span createSpan(String operationName, SpanKind spanKind, SpanContext parentContext, ClientTelemetryTags customAttributes) {
+    static Span createSpan(String operationName, SpanKind spanKind, SpanContext parentContext,
+                           ClientTelemetryTags customAttributes) {
         SpanBuilder spanBuilder = getTracer().spanBuilder(operationName).setSpanKind(spanKind);
 
         if (parentContext != null)

db-client-java/src/test/java/com/eventstore/dbclient/telemetry/StreamsTracingInstrumentationTests.java

@@ -64,7 +64,8 @@ default void testTracingContextIsInjectedAsExpectedWhenUserMetadataIsJsonObject(
     }
 
     @Test
-    default void testTracingContextInjectionIsIgnoredAsExpectedWhenUserMetadataIsNonNullAndNotAJsonObject() throws Throwable {
+    default void testTracingContextInjectionIsIgnoredAsExpectedWhenUserMetadataIsNonNullAndNotAJsonObject()
+            throws Throwable {
         EventStoreDBClient client = getDefaultClient();
         String streamName = generateName();
         byte[] userMetadata = mapper.writeValueAsBytes("clearlynotvalidjson");
@@ -85,6 +86,19 @@ default void testTracingContextInjectionIsIgnoredAsExpectedWhenUserMetadataIsNon
 
         // Assert unchanged
         Assertions.assertArrayEquals(userMetadata, resolvedEvent.getEvent().getUserMetadata());
+
+        List<ReadableSpan> appendSpans = this.getSpansForOperation(ClientTelemetryConstants.Operations.APPEND);
+        Assertions.assertEquals(1, appendSpans.size());
+
+        client.subscribeToStream(streamName, new SubscriptionListener() {
+            @Override
+            public void onEvent(Subscription subscription, ResolvedEvent event) {
+                // do nothing
+            }
+        }).get();
+
+        List<ReadableSpan> subscribeSpans = this.getSpansForOperation(ClientTelemetryConstants.Operations.SUBSCRIBE);
+        Assertions.assertEquals(0, subscribeSpans.size());
     }
 
     @Test