Implement OpenTracing Shim specifying custom propagators

opentracing-shim/src/main/java/io/opentelemetry/opentracingshim/BaseShimObject.java

@@ -6,7 +6,6 @@
 package io.opentelemetry.opentracingshim;
 
 import io.opentelemetry.api.trace.Tracer;
-import io.opentelemetry.context.propagation.ContextPropagators;
 
 abstract class BaseShimObject {
 
@@ -28,7 +27,7 @@ SpanContextShimTable spanContextTable() {
  return telemetryInfo.spanContextTable();
  }
 
- ContextPropagators propagators() {
+ OpenTracingPropagators propagators() {
  return telemetryInfo.propagators();
  }
 }

opentracing-shim/src/main/java/io/opentelemetry/opentracingshim/OpenTracingPropagators.java

@@ -0,0 +1,52 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.opentracingshim;
+
+import io.opentelemetry.context.propagation.TextMapPropagator;
+
+/**
+ * Container for {@link io.opentracing.propagation.Format.Builtin#TEXT_MAP} and {@link
+ * io.opentracing.propagation.Format.Builtin#HTTP_HEADERS} format propagators.
+ */
+public class OpenTracingPropagators {
+ private final TextMapPropagator textMapPropagator;
+ private final TextMapPropagator httpHeadersPropagator;
+
+ OpenTracingPropagators(
+ TextMapPropagator textMapPropagator, TextMapPropagator httpHeadersPropagator) {
+ this.textMapPropagator = textMapPropagator;
+ this.httpHeadersPropagator = httpHeadersPropagator;
+ }
+
+ /**
+ * Returns a new builder instance for {@link OpenTracingPropagators}.
+ *
+ * @return a new builder instance for {@link OpenTracingPropagators}.
+ */
+ public static OpenTracingPropagatorsBuilder builder() {
+ return new OpenTracingPropagatorsBuilder();
+ }
+
+ /**
+ * Returns the propagator for {@link io.opentracing.propagation.Format.Builtin#TEXT_MAP} format.
+ *
+ * @return the propagator for {@link io.opentracing.propagation.Format.Builtin#TEXT_MAP} format.
+ */
+ public TextMapPropagator textMapPropagator() {
+ return textMapPropagator;
+ }
+
+ /**
+ * Returns the propagator for {@link io.opentracing.propagation.Format.Builtin#HTTP_HEADERS}
+ * format.
+ *
+ * @return the propagator for {@link io.opentracing.propagation.Format.Builtin#HTTP_HEADERS}
+ * format.
+ */
+ public TextMapPropagator httpHeadersPropagator() {
+ return httpHeadersPropagator;
+ }
+}

opentracing-shim/src/main/java/io/opentelemetry/opentracingshim/OpenTracingPropagatorsBuilder.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.opentracingshim;
+
+import io.opentelemetry.api.GlobalOpenTelemetry;
+import io.opentelemetry.context.propagation.TextMapPropagator;
+import java.util.Objects;
+
+/** Builder for {@link OpenTracingPropagators}. */
+public class OpenTracingPropagatorsBuilder {
+
+ private TextMapPropagator textMapPropagator =
+ GlobalOpenTelemetry.getPropagators().getTextMapPropagator();
+ private TextMapPropagator httpHeadersPropagator =
+ GlobalOpenTelemetry.getPropagators().getTextMapPropagator();
+
+ /** Set propagator for {@link io.opentracing.propagation.Format.Builtin#TEXT_MAP} format. */
+ public OpenTracingPropagatorsBuilder setTextMap(TextMapPropagator textMapPropagator) {
+ Objects.requireNonNull(textMapPropagator, "textMapPropagator");
+ this.textMapPropagator = textMapPropagator;
+ return this;
+ }
+
+ /** Set propagator for {@link io.opentracing.propagation.Format.Builtin#HTTP_HEADERS} format. */
+ public OpenTracingPropagatorsBuilder setHttpHeaders(TextMapPropagator httpHeadersPropagator) {
+ Objects.requireNonNull(httpHeadersPropagator, "httpHeadersPropagator");
+ this.httpHeadersPropagator = httpHeadersPropagator;
+ return this;
+ }
+
+ /**
+ * Constructs a new instance of the {@link OpenTracingPropagators} based on the builder's values.
+ * If propagators are not set then {@code GlobalOpenTelemetry.getPropagators()} is used.
+ *
+ * @return a new Propagators instance.
+ */
+ public OpenTracingPropagators build() {
+ return new OpenTracingPropagators(textMapPropagator, httpHeadersPropagator);
+ }
+}

opentracing-shim/src/main/java/io/opentelemetry/opentracingshim/OpenTracingShim.java

@@ -18,16 +18,34 @@ public final class OpenTracingShim {
  private OpenTracingShim() {}
 
  /**
- * Creates a {@code io.opentracing.Tracer} shim out of {@code OpenTelemetry.getTracerProvider()}
- * and {@code OpenTelemetry.getPropagators()}.
+ * Creates a {@code io.opentracing.Tracer} shim out of {@code
+ * GlobalOpenTelemetry.getTracerProvider()} and {@code GlobalOpenTelemetry.getPropagators()}.
  *
  * @return a {@code io.opentracing.Tracer}.
  */
  public static io.opentracing.Tracer createTracerShim() {
- return new TracerShim(
- new TelemetryInfo(
- getTracer(GlobalOpenTelemetry.getTracerProvider()),
- GlobalOpenTelemetry.getPropagators()));
+ return createTracerShim(getTracer(GlobalOpenTelemetry.getTracerProvider()));
+ }
+
+ /**
+ * Creates a {@code io.opentracing.Tracer} shim using provided Tracer instance and {@code
+ * GlobalOpenTelemetry.getPropagators()}.
+ *
+ * @return a {@code io.opentracing.Tracer}.
+ */
+ public static io.opentracing.Tracer createTracerShim(Tracer tracer) {
+ return createTracerShim(tracer, OpenTracingPropagators.builder().build());
+ }
+
+ /**
+ * Creates a {@code io.opentracing.Tracer} shim using provided Tracer instance and {@code
+ * OpenTracingPropagators} instance.
+ *
+ * @return a {@code io.opentracing.Tracer}.
+ */
+ public static io.opentracing.Tracer createTracerShim(
+ Tracer tracer, OpenTracingPropagators propagators) {
+ return new TracerShim(new TelemetryInfo(tracer, propagators));
  }
 
  /**
@@ -37,9 +55,12 @@ public static io.opentracing.Tracer createTracerShim() {
  * @return a {@code io.opentracing.Tracer}.
  */
  public static io.opentracing.Tracer createTracerShim(OpenTelemetry openTelemetry) {
- return new TracerShim(
- new TelemetryInfo(
- getTracer(openTelemetry.getTracerProvider()), openTelemetry.getPropagators()));
+ return createTracerShim(
+ getTracer(openTelemetry.getTracerProvider()),
+ OpenTracingPropagators.builder()
+ .setTextMap(openTelemetry.getPropagators().getTextMapPropagator())
+ .setHttpHeaders(openTelemetry.getPropagators().getTextMapPropagator())
+ .build());
  }
 
  private static Tracer getTracer(TracerProvider tracerProvider) {

opentracing-shim/src/main/java/io/opentelemetry/opentracingshim/Propagation.java

@@ -8,6 +8,8 @@
 import io.opentelemetry.api.baggage.Baggage;
 import io.opentelemetry.api.trace.Span;
 import io.opentelemetry.context.Context;
+import io.opentelemetry.context.propagation.TextMapPropagator;
+import io.opentracing.propagation.Format;
 import io.opentracing.propagation.TextMapExtract;
 import io.opentracing.propagation.TextMapInject;
 import java.util.HashMap;
@@ -22,24 +24,21 @@ final class Propagation extends BaseShimObject {
  super(telemetryInfo);
  }
 
- void injectTextMap(SpanContextShim contextShim, TextMapInject carrier) {
+ <C> void injectTextMap(SpanContextShim contextShim, Format<C> format, TextMapInject carrier) {
  Context context = Context.current().with(Span.wrap(contextShim.getSpanContext()));
  context = context.with(contextShim.getBaggage());
 
- propagators().getTextMapPropagator().inject(context, carrier, SETTER_INSTANCE);
+ getPropagator(format).inject(context, carrier, SETTER_INSTANCE);
  }
 
  @Nullable
- SpanContextShim extractTextMap(TextMapExtract carrier) {
+ <C> SpanContextShim extractTextMap(Format<C> format, TextMapExtract carrier) {
  Map<String, String> carrierMap = new HashMap<>();
  for (Map.Entry<String, String> entry : carrier) {
  carrierMap.put(entry.getKey(), entry.getValue());
  }
 
- Context context =
- propagators()
- .getTextMapPropagator()
- .extract(Context.current(), carrierMap, GETTER_INSTANCE);
+ Context context = getPropagator(format).extract(Context.current(), carrierMap, GETTER_INSTANCE);
 
  Span span = Span.fromContext(context);
  if (!span.getSpanContext().isValid()) {
@@ -49,6 +48,13 @@ SpanContextShim extractTextMap(TextMapExtract carrier) {
  return new SpanContextShim(telemetryInfo, span.getSpanContext(), Baggage.fromContext(context));
  }
 
+ private <C> TextMapPropagator getPropagator(Format<C> format) {
+ if (format == Format.Builtin.HTTP_HEADERS) {
+ return propagators().httpHeadersPropagator();
+ }
+ return propagators().textMapPropagator();
+ }
+
  static final class TextMapSetter
  implements io.opentelemetry.context.propagation.TextMapSetter<TextMapInject> {
  private TextMapSetter() {}

opentracing-shim/src/main/java/io/opentelemetry/opentracingshim/TelemetryInfo.java

@@ -7,7 +7,6 @@
 
 import io.opentelemetry.api.baggage.Baggage;
 import io.opentelemetry.api.trace.Tracer;
-import io.opentelemetry.context.propagation.ContextPropagators;
 
 /**
  * Utility class that holds a Tracer, a BaggageManager, and related objects that are core part of
@@ -17,12 +16,12 @@ final class TelemetryInfo {
 
  private final Tracer tracer;
  private final Baggage emptyBaggage;
- private final ContextPropagators propagators;
+ private final OpenTracingPropagators openTracingPropagators;
  private final SpanContextShimTable spanContextTable;
 
- TelemetryInfo(Tracer tracer, ContextPropagators propagators) {
+ TelemetryInfo(Tracer tracer, OpenTracingPropagators openTracingPropagators) {
  this.tracer = tracer;
- this.propagators = propagators;
+ this.openTracingPropagators = openTracingPropagators;
  this.emptyBaggage = Baggage.empty();
  this.spanContextTable = new SpanContextShimTable();
  }
@@ -39,7 +38,7 @@ Baggage emptyBaggage() {
  return emptyBaggage;
  }
 
- ContextPropagators propagators() {
- return propagators;
+ OpenTracingPropagators propagators() {
+ return openTracingPropagators;
  }
 }

opentracing-shim/src/main/java/io/opentelemetry/opentracingshim/TracerShim.java

@@ -65,7 +65,7 @@ public <C> void inject(SpanContext context, Format<C> format, C carrier) {
  if (format == Format.Builtin.TEXT_MAP
  || format == Format.Builtin.TEXT_MAP_INJECT
  || format == Format.Builtin.HTTP_HEADERS) {
- propagation.injectTextMap(contextShim, (TextMapInject) carrier);
+ propagation.injectTextMap(contextShim, format, (TextMapInject) carrier);
  }
  }
 
@@ -76,7 +76,7 @@ public <C> SpanContext extract(Format<C> format, C carrier) {
  if (format == Format.Builtin.TEXT_MAP
  || format == Format.Builtin.TEXT_MAP_EXTRACT
  || format == Format.Builtin.HTTP_HEADERS) {
- return propagation.extractTextMap((TextMapExtract) carrier);
+ return propagation.extractTextMap(format, (TextMapExtract) carrier);
  }
  } catch (RuntimeException e) {
  logger.log(

opentracing-shim/src/test/java/io/opentelemetry/opentracingshim/CustomTextMapPropagator.java

@@ -0,0 +1,43 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.opentracingshim;
+
+import io.opentelemetry.context.Context;
+import io.opentelemetry.context.propagation.TextMapGetter;
+import io.opentelemetry.context.propagation.TextMapPropagator;
+import io.opentelemetry.context.propagation.TextMapSetter;
+import java.util.Collection;
+import java.util.Collections;
+import javax.annotation.Nullable;
+
+class CustomTextMapPropagator implements TextMapPropagator {
+ private boolean extracted;
+ private boolean injected;
+
+ @Override
+ public Collection<String> fields() {
+ return Collections.emptyList();
+ }
+
+ @Override
+ public <C> void inject(Context context, @Nullable C carrier, TextMapSetter<C> setter) {
+ injected = true;
+ }
+
+ @Override
+ public <C> Context extract(Context context, @Nullable C carrier, TextMapGetter<C> getter) {
+ extracted = true;
+ return context;
+ }
+
+ public boolean isExtracted() {
+ return extracted;
+ }
+
+ public boolean isInjected() {
+ return injected;
+ }
+}

opentracing-shim/src/test/java/io/opentelemetry/opentracingshim/OpenTracingShimTest.java

@@ -11,7 +11,9 @@
 
 import io.opentelemetry.api.GlobalOpenTelemetry;
 import io.opentelemetry.api.OpenTelemetry;
+import io.opentelemetry.api.trace.Tracer;
 import io.opentelemetry.context.propagation.ContextPropagators;
+import io.opentelemetry.context.propagation.TextMapPropagator;
 import io.opentelemetry.sdk.trace.SdkTracerProvider;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
@@ -34,9 +36,31 @@ void createTracerShim_fromOpenTelemetryInstance() {
  OpenTelemetry openTelemetry = mock(OpenTelemetry.class);
  SdkTracerProvider sdk = SdkTracerProvider.builder().build();
  when(openTelemetry.getTracerProvider()).thenReturn(sdk);
- when(openTelemetry.getPropagators()).thenReturn(mock(ContextPropagators.class));
+ ContextPropagators contextPropagators = mock(ContextPropagators.class);
+ when(contextPropagators.getTextMapPropagator()).thenReturn(mock(TextMapPropagator.class));
+ when(openTelemetry.getPropagators()).thenReturn(contextPropagators);
 
  TracerShim tracerShim = (TracerShim) OpenTracingShim.createTracerShim(openTelemetry);
  assertThat(tracerShim.tracer()).isEqualTo(sdk.get("opentracingshim"));
  }
+
+ @Test
+ void createTracerShim_withPropagators() {
+ Tracer tracer = mock(Tracer.class);
+
+ TextMapPropagator textMapPropagator = new CustomTextMapPropagator();
+ TextMapPropagator httpHeadersPropagator = new CustomTextMapPropagator();
+
+ TracerShim tracerShim =
+ (TracerShim)
+ OpenTracingShim.createTracerShim(
+ tracer,
+ OpenTracingPropagators.builder()
+ .setTextMap(textMapPropagator)
+ .setHttpHeaders(httpHeadersPropagator)
+ .build());
+
+ assertThat(tracerShim.propagators().textMapPropagator()).isSameAs(textMapPropagator);
+ assertThat(tracerShim.propagators().httpHeadersPropagator()).isSameAs(httpHeadersPropagator);
+ }
 }