Deprecate JaegerPropagator in OpenTelemetry.Extensions.Propagators

src/OpenTelemetry.Extensions.Propagators/JaegerPropagator.cs

@@ -10,6 +10,7 @@ namespace OpenTelemetry.Extensions.Propagators;
 /// <summary>
 /// A text map propagator for Jaeger trace context. See https://www.jaegertracing.io/docs/next-release/client-libraries/#propagation-format.
 /// </summary>
+[Obsolete(ObsoleteMessage)]
 public class JaegerPropagator : TextMapPropagator
 {
     internal const string JaegerHeader = "uber-trace-id";
@@ -19,14 +20,21 @@ public class JaegerPropagator : TextMapPropagator
 
     internal static readonly string[] JaegerDelimiters = [JaegerDelimiter, JaegerDelimiterEncoded];
 
+    private const string ObsoleteMessage = "The Jaeger propagator is obsolete and will be removed in a future version. The Jaeger propagation format has been deprecated in favor of W3C Trace Context. Use TraceContextPropagator instead. See https://www.jaegertracing.io/sdk-migration/#propagation-format and https://github.com/open-telemetry/opentelemetry-specification/issues/4827 for more information.";
+
     private static readonly int TraceId128BitLength = "0af7651916cd43dd8448eb211c80319c".Length;
     private static readonly int SpanIdLength = "00f067aa0ba902b7".Length;
 
     /// <inheritdoc/>
+#pragma warning disable CS0809 // Obsolete member overrides non-obsolete member
     public override ISet<string> Fields => new HashSet<string> { JaegerHeader };
+#pragma warning restore CS0809 // Obsolete member overrides non-obsolete member
 
     /// <inheritdoc/>
+    [Obsolete(ObsoleteMessage)]
+#pragma warning disable CS0809 // Obsolete member overrides non-obsolete member
     public override PropagationContext Extract<T>(PropagationContext context, T carrier, Func<T, string, IEnumerable<string>?> getter)
+#pragma warning restore CS0809 // Obsolete member overrides non-obsolete member
     {
         if (context.ActivityContext.IsValid())
         {
@@ -81,7 +89,10 @@ public override PropagationContext Extract<T>(PropagationContext context, T carr
     }
 
     /// <inheritdoc/>
+    [Obsolete(ObsoleteMessage)]
+#pragma warning disable CS0809 // Obsolete member overrides non-obsolete member
     public override void Inject<T>(PropagationContext context, T carrier, Action<T, string, string> setter)
+#pragma warning restore CS0809 // Obsolete member overrides non-obsolete member
     {
         // from https://www.jaegertracing.io/docs/next-release/client-libraries/#propagation-format
         // parent id is optional and deprecated, will not attempt to set it.

src/OpenTelemetry.Extensions.Propagators/README.md

@@ -8,6 +8,14 @@ propagators by following the [OpenTelemetry specification](https://opentelemetry
 (currently supporting [B3](https://github.com/openzipkin/b3-propagation) format)
 for tracing.
 
+> [!NOTE]
+> `JaegerPropagator` is deprecated and will be removed in a future version.
+> The Jaeger propagation format has been deprecated in favor of W3C Trace Context.
+> Use `TraceContextPropagator` from the `OpenTelemetry` package instead.
+> See [Jaeger's migration guide](https://www.jaegertracing.io/sdk-migration/#propagation-format)
+> and [OpenTelemetry specification issue #4827](https://github.com/open-telemetry/opentelemetry-specification/issues/4827)
+> for more information.
+
 ## Installation
 
 Add a reference to the

test/OpenTelemetry.Extensions.Propagators.Tests/JaegerPropagatorTests.cs

@@ -44,7 +44,9 @@ public void ExtractReturnsOriginalContextIfContextIsAlreadyValid()
         var headers = new Dictionary<string, string[]>();
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         var result = new JaegerPropagator().Extract(propagationContext, headers, Getter);
+#pragma warning restore CS0618
 
         // assert
         Assert.Equal(propagationContext, result);
@@ -57,7 +59,9 @@ public void ExtractReturnsOriginalContextIfCarrierIsNull()
         var propagationContext = default(PropagationContext);
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         var result = new JaegerPropagator().Extract(propagationContext, null, Getter!);
+#pragma warning restore CS0618
 
         // assert
         Assert.Equal(propagationContext, result);
@@ -72,7 +76,9 @@ public void ExtractReturnsOriginalContextIfGetterIsNull()
         var headers = new Dictionary<string, string[]>();
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         var result = new JaegerPropagator().Extract(propagationContext, headers, null!);
+#pragma warning restore CS0618
 
         // assert
         Assert.Equal(propagationContext, result);
@@ -102,7 +108,9 @@ public void ExtractReturnsOriginalContextIfHeaderIsNotValid(string traceId, stri
         var headers = new Dictionary<string, string[]> { { JaegerHeader, [formattedHeader] } };
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         var result = new JaegerPropagator().Extract(propagationContext, headers, Getter);
+#pragma warning restore CS0618
 
         // assert
         Assert.Equal(propagationContext, result);
@@ -141,7 +149,9 @@ public void ExtractReturnsNewContextIfHeaderIsValid(string traceId, string spanI
         var headers = new Dictionary<string, string[]> { { JaegerHeader, [formattedHeader] } };
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         var result = new JaegerPropagator().Extract(propagationContext, headers, Getter);
+#pragma warning restore CS0618
 
         // assert
         Assert.Equal(traceId.PadLeft(TraceId.Length, '0'), result.ActivityContext.TraceId.ToString());
@@ -158,7 +168,9 @@ public void InjectDoesNoopIfContextIsInvalid()
         var headers = new Dictionary<string, string>();
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         new JaegerPropagator().Inject(propagationContext, headers, Setter);
+#pragma warning restore CS0618
 
         // assert
         Assert.Empty(headers);
@@ -175,7 +187,9 @@ public void InjectDoesNoopIfCarrierIsNull()
             default);
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         new JaegerPropagator().Inject(propagationContext, null, Setter!);
+#pragma warning restore CS0618
 
         // assert
     }
@@ -193,7 +207,9 @@ public void InjectDoesNoopIfSetterIsNull()
         var headers = new Dictionary<string, string>();
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         new JaegerPropagator().Inject(propagationContext, headers, null!);
+#pragma warning restore CS0618
 
         // assert
         Assert.Empty(headers);
@@ -221,7 +237,9 @@ public void InjectWillAddJaegerFormattedTraceToCarrier(string sampledFlag)
         var headers = new Dictionary<string, string>();
 
         // act
+#pragma warning disable CS0618 // Type or member is obsolete
         new JaegerPropagator().Inject(propagationContext, headers, Setter);
+#pragma warning restore CS0618
 
         // assert
         Assert.Single(headers);