read sentry-trace header for sampled / non sampled TraceFlags

Author: adinauer

sentry-opentelemetry/sentry-opentelemetry-otlp/src/main/java/io/sentry/opentelemetry/otlp/OpenTelemetryOtlpPropagator.java

@@ -90,11 +90,16 @@ public <C> Context extract(
       final Baggage baggage = Baggage.fromHeader(baggageString);
       final @NotNull TraceState traceState = TraceState.getDefault();
 
+      final @NotNull TraceFlags traceFlags =
+          Boolean.FALSE.equals(sentryTraceHeader.isSampled())
+              ? TraceFlags.getDefault()
+              : TraceFlags.getSampled();
+
       SpanContext otelSpanContext =
           SpanContext.createFromRemoteParent(
               sentryTraceHeader.getTraceId().toString(),
               sentryTraceHeader.getSpanId().toString(),
-              TraceFlags.getSampled(),
+              traceFlags,
               traceState);
 
       Span wrappedSpan = Span.wrap(otelSpanContext);

sentry-opentelemetry/sentry-opentelemetry-otlp/src/test/kotlin/OtelSentryPropagatorTest.kt

@@ -12,6 +12,7 @@ import io.sentry.Sentry
 import kotlin.test.BeforeTest
 import kotlin.test.Test
 import kotlin.test.assertEquals
+import kotlin.test.assertFalse
 import kotlin.test.assertNull
 import kotlin.test.assertTrue
 
@@ -67,6 +68,32 @@ class OpenTelemetryOtlpPropagatorTest {
     )
   }
 
+  @Test
+  fun `extract sets sampled trace flag when sentry-trace has sampled=0`() {
+    val propagator = OpenTelemetryOtlpPropagator()
+    val carrier: Map<String, String> =
+      mapOf("sentry-trace" to "f9118105af4a2d42b4124532cd1065ff-424cffc8f94feeee-0")
+    val newContext = propagator.extract(Context.root(), carrier, MapGetter())
+
+    val span = Span.fromContext(newContext)
+    assertEquals("f9118105af4a2d42b4124532cd1065ff", span.spanContext.traceId)
+    assertEquals("424cffc8f94feeee", span.spanContext.spanId)
+    assertFalse(span.spanContext.isSampled)
+  }
+
+  @Test
+  fun `extract sets sampled trace flag when sentry-trace has no sampling decision`() {
+    val propagator = OpenTelemetryOtlpPropagator()
+    val carrier: Map<String, String> =
+      mapOf("sentry-trace" to "f9118105af4a2d42b4124532cd1065ff-424cffc8f94feeee")
+    val newContext = propagator.extract(Context.root(), carrier, MapGetter())
+
+    val span = Span.fromContext(newContext)
+    assertEquals("f9118105af4a2d42b4124532cd1065ff", span.spanContext.traceId)
+    assertEquals("424cffc8f94feeee", span.spanContext.spanId)
+    assertTrue(span.spanContext.isSampled)
+  }
+
   @Test
   fun `injects headers`() {
     val propagator = OpenTelemetryOtlpPropagator()