Migrate context extraction calls to context-first APIs

components/context/src/main/java/datadog/context/propagation/CompositePropagator.java

@@ -14,8 +14,8 @@ class CompositePropagator implements Propagator {
 
   @Override
   public <C> void inject(Context context, C carrier, CarrierSetter<C> setter) {
-    for (Propagator propagator : this.propagators) {
-      propagator.inject(context, carrier, setter);
+    for (int i = this.propagators.length - 1; i >= 0; i--) {
+      this.propagators[i].inject(context, carrier, setter);
     }
   }
 

components/context/src/main/java/datadog/context/propagation/Propagators.java

@@ -78,7 +78,8 @@ public static Propagator noop() {
    * Creates a composite propagator.
    *
    * @param propagators the elements that composes the returned propagator.
-   * @return the composite propagator that will apply the propagators in their given order.
+   * @return the composite propagator that will apply the propagators in their given order for
+   *     context extraction, and reverse given order for context injection.
    */
   public static Propagator composite(Propagator... propagators) {
     if (propagators.length == 0) {

dd-trace-core/src/main/java/datadog/trace/core/CoreTracer.java

@@ -32,7 +32,6 @@
 import datadog.trace.api.InstrumenterConfig;
 import datadog.trace.api.StatsDClient;
 import datadog.trace.api.TraceConfig;
-import datadog.trace.api.TracePropagationStyle;
 import datadog.trace.api.config.GeneralConfig;
 import datadog.trace.api.experimental.DataStreamsCheckpointer;
 import datadog.trace.api.flare.TracerFlare;
@@ -79,7 +78,6 @@
 import datadog.trace.common.writer.WriterFactory;
 import datadog.trace.common.writer.ddintake.DDIntakeTraceInterceptor;
 import datadog.trace.context.TraceScope;
-import datadog.trace.core.datastreams.DataStreamContextInjector;
 import datadog.trace.core.datastreams.DataStreamsMonitoring;
 import datadog.trace.core.datastreams.DefaultDataStreamsMonitoring;
 import datadog.trace.core.flare.TracerFlarePoller;
@@ -719,13 +717,8 @@ private CoreTracer(
     HttpCodec.Extractor builtExtractor =
         extractor == null ? HttpCodec.createExtractor(config, this::captureTraceConfig) : extractor;
     builtExtractor = this.dataStreamsMonitoring.extractor(builtExtractor);
-    // Create all HTTP injectors plus the DSM one
-    Map<TracePropagationStyle, HttpCodec.Injector> injectors =
-        HttpCodec.allInjectorsFor(config, invertMap(baggageMapping));
-    DataStreamContextInjector dataStreamContextInjector = this.dataStreamsMonitoring.injector();
     // Store all propagators to propagation
-    this.propagation =
-        new CorePropagation(builtExtractor, injector, injectors, dataStreamContextInjector);
+    this.propagation = new CorePropagation(builtExtractor, this.dataStreamsMonitoring.injector());
 
     // Check if standalone AppSec is enabled:
     // If enabled, use the standalone AppSec propagator by default that will limit tracing concern

dd-trace-core/src/main/java/datadog/trace/core/propagation/CorePropagation.java

@@ -1,81 +1,27 @@
 package datadog.trace.core.propagation;
 
-import datadog.trace.api.Config;
-import datadog.trace.api.TracePropagationStyle;
 import datadog.trace.bootstrap.instrumentation.api.AgentPropagation;
 import datadog.trace.bootstrap.instrumentation.api.AgentSpan;
-import datadog.trace.bootstrap.instrumentation.api.AgentSpanContext;
-import datadog.trace.core.DDSpanContext;
 import datadog.trace.core.datastreams.DataStreamContextInjector;
 import java.util.LinkedHashMap;
-import java.util.Map;
 
 public class CorePropagation implements AgentPropagation {
-  private final HttpCodec.Injector injector;
-  private final Map<TracePropagationStyle, HttpCodec.Injector> injectors;
   private final DataStreamContextInjector dataStreamContextInjector;
   private final HttpCodec.Extractor extractor;
 
   /**
    * Constructor
    *
    * @param extractor The context extractor.
-   * @param defaultInjector The default injector when no {@link TracePropagationStyle} given.
-   * @param injectors All the other injectors available for context injection.
    * @param dataStreamContextInjector The DSM context injector, as a specific object until generic
    *     context injection is available.
    */
   public CorePropagation(
-      HttpCodec.Extractor extractor,
-      HttpCodec.Injector defaultInjector,
-      Map<TracePropagationStyle, HttpCodec.Injector> injectors,
-      DataStreamContextInjector dataStreamContextInjector) {
+      HttpCodec.Extractor extractor, DataStreamContextInjector dataStreamContextInjector) {
     this.extractor = extractor;
-    this.injector = defaultInjector;
-    this.injectors = injectors;
     this.dataStreamContextInjector = dataStreamContextInjector;
   }
 
-  @Override
-  public <C> void inject(final AgentSpan span, final C carrier, final Setter<C> setter) {
-    inject(span.context(), carrier, setter, null);
-  }
-
-  @Override
-  public <C> void inject(AgentSpanContext context, C carrier, Setter<C> setter) {
-    inject(context, carrier, setter, null);
-  }
-
-  @Override
-  public <C> void inject(AgentSpan span, C carrier, Setter<C> setter, TracePropagationStyle style) {
-    inject(span.context(), carrier, setter, style);
-  }
-
-  private <C> void inject(
-      AgentSpanContext context, C carrier, Setter<C> setter, TracePropagationStyle style) {
-    if (!(context instanceof DDSpanContext)) {
-      return;
-    }
-
-    final DDSpanContext ddSpanContext = (DDSpanContext) context;
-    ddSpanContext.getTraceCollector().setSamplingPriorityIfNecessary();
-
-    /**
-     * If the experimental appsec standalone feature is enabled and appsec propagation is disabled
-     * (no ASM events), stop propagation
-     */
-    if (Config.get().isAppSecStandaloneEnabled()
-        && !ddSpanContext.getPropagationTags().isAppsecPropagationEnabled()) {
-      return;
-    }
-
-    if (null == style) {
-      injector.inject(ddSpanContext, carrier, setter);
-    } else {
-      injectors.get(style).inject(ddSpanContext, carrier, setter);
-    }
-  }
-
   @Override
   public <C> void injectPathwayContext(
       AgentSpan span, C carrier, Setter<C> setter, LinkedHashMap<String, String> sortedTags) {
@@ -100,9 +46,4 @@ public <C> void injectPathwayContextWithoutSendingStats(
     this.dataStreamContextInjector.injectPathwayContextWithoutSendingStats(
         span, carrier, setter, sortedTags);
   }
-
-  @Override
-  public <C> AgentSpanContext.Extracted extract(final C carrier, final ContextVisitor<C> getter) {
-    return extractor.extract(carrier, getter);
-  }
 }

dd-trace-core/src/test/groovy/datadog/trace/core/CoreTracerTest.groovy

@@ -19,8 +19,6 @@ import datadog.trace.common.sampling.Sampler
 import datadog.trace.common.writer.DDAgentWriter
 import datadog.trace.common.writer.ListWriter
 import datadog.trace.common.writer.LoggingWriter
-import datadog.trace.core.datastreams.DataStreamContextExtractor
-import datadog.trace.core.propagation.HttpCodec
 import datadog.trace.core.tagprocessor.TagsPostProcessorFactory
 import datadog.trace.core.test.DDCoreSpecification
 import okhttp3.HttpUrl
@@ -55,9 +53,6 @@ class CoreTracerTest extends DDCoreSpecification {
     tracer.writer instanceof DDAgentWriter
     tracer.statsDClient != null && tracer.statsDClient != StatsDClient.NO_OP
 
-    tracer.propagate().injector instanceof HttpCodec.CompoundInjector
-    tracer.propagate().extractor instanceof DataStreamContextExtractor
-
     cleanup:
     tracer.close()
   }