Ensure that invalid spans/traces to not trigger snapshot registration.

Author: tduncan

profiler/src/main/java/com/splunk/opentelemetry/profiler/snapshot/SnapshotProfilingSignalPropagator.java

@@ -50,8 +50,12 @@ public <C> void inject(Context context, C carrier, TextMapSetter<C> setter) {
   @Override
   public <C> Context extract(Context context, C carrier, TextMapGetter<C> getter) {
     Volume volume = Volume.fromString(getter.get(carrier, PROFILING_SIGNAL));
+    if (volume == Volume.OFF) {
+      return context;
+    }
+
     SpanContext spanContext = Span.fromContext(context).getSpanContext();
-    if (volume == Volume.HIGHEST) {
+    if (spanContext.isValid()) {
       registry.register(spanContext);
     }
     return context;

profiler/src/test/java/com/splunk/opentelemetry/profiler/snapshot/DistributedProfilingSignalTest.java

@@ -23,11 +23,7 @@
 import com.splunk.opentelemetry.profiler.snapshot.simulation.ExitCall;
 import com.splunk.opentelemetry.profiler.snapshot.simulation.Message;
 import com.splunk.opentelemetry.profiler.snapshot.simulation.Server;
-import io.opentelemetry.api.trace.SpanContext;
 import java.time.Duration;
-import java.util.Collections;
-import java.util.HashSet;
-import java.util.Set;
 import java.util.function.UnaryOperator;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.extension.RegisterExtension;
@@ -88,28 +84,4 @@ private UnaryOperator<Message> delayOf(Duration duration) {
       }
     };
   }
-
-  private static class RecordingTraceRegistry extends TraceRegistry {
-    private final Set<String> registeredTraceIds = new HashSet<>();
-
-    @Override
-    public void register(SpanContext spanContext) {
-      registeredTraceIds.add(spanContext.getTraceId());
-      super.register(spanContext);
-    }
-
-    @Override
-    public boolean isRegistered(SpanContext spanContext) {
-      return super.isRegistered(spanContext);
-    }
-
-    @Override
-    public void unregister(SpanContext spanContext) {
-      super.unregister(spanContext);
-    }
-
-    Set<String> registeredTraceIds() {
-      return Collections.unmodifiableSet(registeredTraceIds);
-    }
-  }
 }

profiler/src/test/java/com/splunk/opentelemetry/profiler/snapshot/RecordingTraceRegistry.java

@@ -0,0 +1,35 @@
+package com.splunk.opentelemetry.profiler.snapshot;
+
+import io.opentelemetry.api.trace.SpanContext;
+
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.Set;
+
+/**
+ * Test only version of {@link TraceRegistry} that keeps a record of every trace ID registered over
+ * the lifetime of the instance.
+ */
+class RecordingTraceRegistry extends TraceRegistry {
+  private final Set<String> registeredTraceIds = new HashSet<>();
+
+  @Override
+  public void register(SpanContext spanContext) {
+    registeredTraceIds.add(spanContext.getTraceId());
+    super.register(spanContext);
+  }
+
+  @Override
+  public boolean isRegistered(SpanContext spanContext) {
+    return super.isRegistered(spanContext);
+  }
+
+  @Override
+  public void unregister(SpanContext spanContext) {
+    super.unregister(spanContext);
+  }
+
+  Set<String> registeredTraceIds() {
+    return Collections.unmodifiableSet(registeredTraceIds);
+  }
+}

profiler/src/test/java/com/splunk/opentelemetry/profiler/snapshot/SnapshotProfilingSignalPropagatorTest.java

@@ -32,7 +32,7 @@ class SnapshotProfilingSignalPropagatorTest {
 
   @RegisterExtension public final ObservableCarrier carrier = new ObservableCarrier();
 
-  private final TraceRegistry registry = new TraceRegistry();
+  private final RecordingTraceRegistry registry = new RecordingTraceRegistry();
   private final SnapshotProfilingSignalPropagator propagator =
       new SnapshotProfilingSignalPropagator(registry);
 
@@ -105,6 +105,16 @@ void doNotRegisterTraceForProfilingWhenTraceSnapshotVolumeIsMissing(Tracer trace
     assertThat(registry.isRegistered(span.getSpanContext())).isFalse();
   }
 
+  @Test
+  void doNotRegisterTraceForProfilingWhenSpanIsNotFoundInContext() {
+    carrier.set("splunk.trace.snapshot.volume", Volume.HIGHEST.toString());
+    var context = Context.current();
+
+    propagator.extract(context, carrier, carrier);
+
+    assertEquals(Collections.emptySet(), registry.registeredTraceIds());
+  }
+
   @Test
   void extractReturnsProvidedContextWhenNotRegisteringTraceForProfiling(Tracer tracer) {
     var span = tracer.spanBuilder("span").startSpan();