Add opt-in support for emitting exceptions as log signals

instrumentation-api-incubator/build.gradle.kts

@@ -102,7 +102,21 @@ tasks {
     inputs.dir(jflexOutputDir)
   }
 
+  val testExceptionSignalLogs by registering(Test::class) {
+    testClassesDirs = sourceSets.test.get().output.classesDirs
+    classpath = sourceSets.test.get().runtimeClasspath
+    jvmArgs("-Dotel.semconv.exception.signal.opt-in=logs")
+    inputs.dir(jflexOutputDir)
+  }
+
+  val testExceptionSignalLogsDup by registering(Test::class) {
+    testClassesDirs = sourceSets.test.get().output.classesDirs
+    classpath = sourceSets.test.get().runtimeClasspath
+    jvmArgs("-Dotel.semconv.exception.signal.opt-in=logs/dup")
+    inputs.dir(jflexOutputDir)
+  }
+
   check {
-    dependsOn(testStableSemconv, testBothSemconv)
+    dependsOn(testStableSemconv, testBothSemconv, testExceptionSignalLogs, testExceptionSignalLogsDup)
   }
 }

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/builder/internal/DefaultHttpClientInstrumenterBuilder.java

@@ -14,6 +14,7 @@
 import io.opentelemetry.instrumentation.api.incubator.config.internal.CommonConfig;
 import io.opentelemetry.instrumentation.api.incubator.semconv.http.HttpClientExperimentalMetrics;
 import io.opentelemetry.instrumentation.api.incubator.semconv.http.HttpClientServicePeerAttributesExtractor;
+import io.opentelemetry.instrumentation.api.incubator.semconv.http.HttpExceptionEventExtractors;
 import io.opentelemetry.instrumentation.api.incubator.semconv.http.HttpExperimentalAttributesExtractor;
 import io.opentelemetry.instrumentation.api.incubator.semconv.http.internal.HttpClientUrlTemplateUtil;
 import io.opentelemetry.instrumentation.api.instrumenter.AttributesExtractor;
@@ -223,6 +224,7 @@ public Instrumenter<REQUEST, RESPONSE> build() {
             .addAttributesExtractors(additionalExtractors)
             .addOperationMetrics(HttpClientMetrics.get())
             .setSchemaUrl(SchemaUrls.V1_37_0);
+    Experimental.setExceptionEventExtractor(builder, HttpExceptionEventExtractors.client());
     if (emitExperimentalHttpClientTelemetry) {
       builder
           .addAttributesExtractor(HttpExperimentalAttributesExtractor.create(attributesGetter))

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/builder/internal/DefaultHttpServerInstrumenterBuilder.java

@@ -11,6 +11,7 @@
 import io.opentelemetry.api.OpenTelemetry;
 import io.opentelemetry.context.propagation.TextMapGetter;
 import io.opentelemetry.instrumentation.api.incubator.config.internal.CommonConfig;
+import io.opentelemetry.instrumentation.api.incubator.semconv.http.HttpExceptionEventExtractors;
 import io.opentelemetry.instrumentation.api.incubator.semconv.http.HttpExperimentalAttributesExtractor;
 import io.opentelemetry.instrumentation.api.incubator.semconv.http.HttpServerExperimentalMetrics;
 import io.opentelemetry.instrumentation.api.instrumenter.AttributesExtractor;
@@ -19,6 +20,7 @@
 import io.opentelemetry.instrumentation.api.instrumenter.SpanKindExtractor;
 import io.opentelemetry.instrumentation.api.instrumenter.SpanNameExtractor;
 import io.opentelemetry.instrumentation.api.instrumenter.SpanStatusExtractor;
+import io.opentelemetry.instrumentation.api.internal.Experimental;
 import io.opentelemetry.instrumentation.api.semconv.http.HttpServerAttributesExtractor;
 import io.opentelemetry.instrumentation.api.semconv.http.HttpServerAttributesExtractorBuilder;
 import io.opentelemetry.instrumentation.api.semconv.http.HttpServerAttributesGetter;
@@ -215,6 +217,7 @@ public InstrumenterBuilder<REQUEST, RESPONSE> instrumenterBuilder() {
             .addContextCustomizer(httpServerRouteBuilder.build())
             .addOperationMetrics(HttpServerMetrics.get())
             .setSchemaUrl(SchemaUrls.V1_37_0);
+    Experimental.setExceptionEventExtractor(builder, HttpExceptionEventExtractors.server());
     if (emitExperimentalHttpServerTelemetry) {
       builder
           .addAttributesExtractor(HttpExperimentalAttributesExtractor.create(attributesGetter))

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/instrumenter/ExceptionEventExtractor.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.incubator.instrumenter;
+
+import io.opentelemetry.api.logs.LogRecordBuilder;
+import io.opentelemetry.api.logs.Severity;
+import io.opentelemetry.context.Context;
+import io.opentelemetry.instrumentation.api.internal.InternalExceptionEventExtractor;
+
+/**
+ * Extractor that populates the exception event {@link LogRecordBuilder} for a request. This allows
+ * instrumentations to set the event name, severity, and any additional attributes on the exception
+ * log event.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+@FunctionalInterface
+public interface ExceptionEventExtractor<REQUEST> extends InternalExceptionEventExtractor<REQUEST> {
+
+  /**
+   * Returns an {@link ExceptionEventExtractor} that always sets the given event name and severity.
+   */
+  static <REQUEST> ExceptionEventExtractor<REQUEST> create(String eventName, Severity severity) {
+    return (logRecordBuilder, context, request) -> {
+      logRecordBuilder.setEventName(eventName);
+      logRecordBuilder.setSeverity(severity);
+    };
+  }
+
+  /**
+   * Populates the exception event {@link LogRecordBuilder} with the event name, severity, and any
+   * additional attributes for the given context and request.
+   */
+  @Override
+  void extract(LogRecordBuilder logRecordBuilder, Context context, REQUEST request);
+}

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/semconv/db/DbExceptionEventExtractors.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.incubator.semconv.db;
+
+import io.opentelemetry.api.logs.Severity;
+import io.opentelemetry.instrumentation.api.incubator.instrumenter.ExceptionEventExtractor;
+
+/**
+ * {@link ExceptionEventExtractor} constants for DB client instrumentations.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+public final class DbExceptionEventExtractors {
+
+  /** Exception event extractor for DB client spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> client() {
+    return ExceptionEventExtractor.create("db.client.operation.exception", Severity.WARN);
+  }
+
+  private DbExceptionEventExtractors() {}
+}

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/semconv/genai/GenAiExceptionEventExtractors.java

@@ -0,0 +1,25 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.incubator.semconv.genai;
+
+import io.opentelemetry.api.logs.Severity;
+import io.opentelemetry.instrumentation.api.incubator.instrumenter.ExceptionEventExtractor;
+
+/**
+ * {@link ExceptionEventExtractor} constants for GenAI client instrumentations.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+public final class GenAiExceptionEventExtractors {
+
+  /** Exception event extractor for GenAI client spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> client() {
+    return ExceptionEventExtractor.create("gen_ai.client.operation.exception", Severity.WARN);
+  }
+
+  private GenAiExceptionEventExtractors() {}
+}

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/semconv/http/HttpExceptionEventExtractors.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.incubator.semconv.http;
+
+import io.opentelemetry.api.logs.Severity;
+import io.opentelemetry.instrumentation.api.incubator.instrumenter.ExceptionEventExtractor;
+
+/**
+ * {@link ExceptionEventExtractor} constants for HTTP client and server instrumentations.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+public final class HttpExceptionEventExtractors {
+
+  /** Exception event extractor for HTTP client spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> client() {
+    return ExceptionEventExtractor.create("http.client.request.exception", Severity.WARN);
+  }
+
+  /** Exception event extractor for HTTP server spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> server() {
+    return ExceptionEventExtractor.create("http.server.request.exception", Severity.ERROR);
+  }
+
+  private HttpExceptionEventExtractors() {}
+}

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/semconv/messaging/MessagingExceptionEventExtractors.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.incubator.semconv.messaging;
+
+import io.opentelemetry.api.logs.Severity;
+import io.opentelemetry.instrumentation.api.incubator.instrumenter.ExceptionEventExtractor;
+
+/**
+ * {@link ExceptionEventExtractor} constants for messaging instrumentations.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+public final class MessagingExceptionEventExtractors {
+
+  /** Exception event extractor for messaging client operation spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> client() {
+    return ExceptionEventExtractor.create("messaging.client.operation.exception", Severity.WARN);
+  }
+
+  /** Exception event extractor for messaging process spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> process() {
+    return ExceptionEventExtractor.create("messaging.process.exception", Severity.ERROR);
+  }
+
+  private MessagingExceptionEventExtractors() {}
+}

instrumentation-api-incubator/src/main/java/io/opentelemetry/instrumentation/api/incubator/semconv/rpc/RpcExceptionEventExtractors.java

@@ -0,0 +1,30 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.instrumentation.api.incubator.semconv.rpc;
+
+import io.opentelemetry.api.logs.Severity;
+import io.opentelemetry.instrumentation.api.incubator.instrumenter.ExceptionEventExtractor;
+
+/**
+ * {@link ExceptionEventExtractor} constants for RPC client and server instrumentations.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+public final class RpcExceptionEventExtractors {
+
+  /** Exception event extractor for RPC client spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> client() {
+    return ExceptionEventExtractor.create("rpc.client.call.exception", Severity.WARN);
+  }
+
+  /** Exception event extractor for RPC server spans. */
+  public static <REQUEST> ExceptionEventExtractor<REQUEST> server() {
+    return ExceptionEventExtractor.create("rpc.server.call.exception", Severity.ERROR);
+  }
+
+  private RpcExceptionEventExtractors() {}
+}

instrumentation-api/build.gradle.kts

@@ -44,4 +44,20 @@ tasks {
     jvmArgs("--add-opens=java.base/java.util=ALL-UNNAMED")
     jvmArgs("-XX:+IgnoreUnrecognizedVMOptions")
   }
+
+  val testExceptionSignalLogs by registering(Test::class) {
+    testClassesDirs = sourceSets.test.get().output.classesDirs
+    classpath = sourceSets.test.get().runtimeClasspath
+    jvmArgs("-Dotel.semconv.exception.signal.opt-in=logs")
+  }
+
+  val testExceptionSignalLogsDup by registering(Test::class) {
+    testClassesDirs = sourceSets.test.get().output.classesDirs
+    classpath = sourceSets.test.get().runtimeClasspath
+    jvmArgs("-Dotel.semconv.exception.signal.opt-in=logs/dup")
+  }
+
+  check {
+    dependsOn(testExceptionSignalLogs, testExceptionSignalLogsDup)
+  }
 }

instrumentation-api/src/main/java/io/opentelemetry/instrumentation/api/instrumenter/Instrumenter.java

@@ -5,9 +5,17 @@
 
 package io.opentelemetry.instrumentation.api.instrumenter;
 
+import static io.opentelemetry.instrumentation.api.internal.SemconvExceptionSignal.emitExceptionAsLogs;
+import static io.opentelemetry.instrumentation.api.internal.SemconvExceptionSignal.emitExceptionAsSpanEvents;
+import static io.opentelemetry.semconv.ExceptionAttributes.EXCEPTION_MESSAGE;
+import static io.opentelemetry.semconv.ExceptionAttributes.EXCEPTION_STACKTRACE;
+import static io.opentelemetry.semconv.ExceptionAttributes.EXCEPTION_TYPE;
 import static java.util.concurrent.TimeUnit.SECONDS;
 
 import io.opentelemetry.api.OpenTelemetry;
+import io.opentelemetry.api.incubator.logs.ExtendedLogRecordBuilder;
+import io.opentelemetry.api.logs.LogRecordBuilder;
+import io.opentelemetry.api.logs.Logger;
 import io.opentelemetry.api.trace.Span;
 import io.opentelemetry.api.trace.SpanBuilder;
 import io.opentelemetry.api.trace.SpanKind;
@@ -18,7 +26,10 @@
 import io.opentelemetry.instrumentation.api.internal.InstrumenterAccess;
 import io.opentelemetry.instrumentation.api.internal.InstrumenterContext;
 import io.opentelemetry.instrumentation.api.internal.InstrumenterUtil;
+import io.opentelemetry.instrumentation.api.internal.InternalExceptionEventExtractor;
 import io.opentelemetry.instrumentation.api.internal.SupportabilityMetrics;
+import java.io.PrintWriter;
+import java.io.StringWriter;
 import java.time.Instant;
 import javax.annotation.Nullable;
 
@@ -72,6 +83,7 @@ public static <REQUEST, RESPONSE> InstrumenterBuilder<REQUEST, RESPONSE> builder
 
   private final String instrumentationName;
   private final Tracer tracer;
+  @Nullable private final Logger logger;
   private final SpanNameExtractor<? super REQUEST> spanNameExtractor;
   private final SpanKindExtractor<? super REQUEST> spanKindExtractor;
   private final SpanStatusExtractor<? super REQUEST, ? super RESPONSE> spanStatusExtractor;
@@ -82,6 +94,7 @@ public static <REQUEST, RESPONSE> InstrumenterBuilder<REQUEST, RESPONSE> builder
   private final AttributesExtractor<? super REQUEST, ? super RESPONSE>[]
       operationListenerAttributesExtractors;
   private final ErrorCauseExtractor errorCauseExtractor;
+  @Nullable private final InternalExceptionEventExtractor<? super REQUEST> exceptionEventExtractor;
   private final boolean propagateOperationListenersToOnEnd;
   private final boolean enabled;
   private final SpanSuppressor spanSuppressor;
@@ -91,6 +104,10 @@ public static <REQUEST, RESPONSE> InstrumenterBuilder<REQUEST, RESPONSE> builder
   Instrumenter(InstrumenterBuilder<REQUEST, RESPONSE> builder) {
     this.instrumentationName = builder.instrumentationName;
     this.tracer = builder.buildTracer();
+    this.logger =
+        emitExceptionAsLogs() && builder.exceptionEventExtractor != null
+            ? builder.buildLogger()
+            : null;
     this.spanNameExtractor = builder.spanNameExtractor;
     this.spanKindExtractor = builder.spanKindExtractor;
     this.spanStatusExtractor = builder.spanStatusExtractor;
@@ -101,6 +118,7 @@ public static <REQUEST, RESPONSE> InstrumenterBuilder<REQUEST, RESPONSE> builder
     this.operationListenerAttributesExtractors =
         builder.operationListenerAttributesExtractors.toArray(new AttributesExtractor[0]);
     this.errorCauseExtractor = builder.errorCauseExtractor;
+    this.exceptionEventExtractor = builder.exceptionEventExtractor;
     this.propagateOperationListenersToOnEnd = builder.propagateOperationListenersToOnEnd;
     this.enabled = builder.enabled;
     this.spanSuppressor = builder.buildSpanSuppressor();
@@ -260,7 +278,12 @@ private void doEnd(
 
     if (error != null) {
       error = errorCauseExtractor.extract(error);
-      span.recordException(error);
+      if (emitExceptionAsSpanEvents()) {
+        span.recordException(error);
+      }
+      if (emitExceptionAsLogs() && exceptionEventExtractor != null) {
+        emitExceptionLog(context, error, request);
+      }
     }
 
     UnsafeAttributes attributes = new UnsafeAttributes();
@@ -301,6 +324,32 @@ private void doEnd(
     }
   }
 
+  private void emitExceptionLog(Context context, Throwable throwable, REQUEST request) {
+    if (logger == null || exceptionEventExtractor == null) {
+      // this condition is to keep nullaway happy
+      // doEnd already guards on exceptionEventExtractor != null, so this is unreachable
+      return;
+    }
+    LogRecordBuilder logRecordBuilder = logger.logRecordBuilder();
+    logRecordBuilder.setContext(context);
+    exceptionEventExtractor.extract(logRecordBuilder, context, request);
+
+    if (logRecordBuilder instanceof ExtendedLogRecordBuilder) {
+      ((ExtendedLogRecordBuilder) logRecordBuilder).setException(throwable);
+    } else {
+      logRecordBuilder.setAttribute(EXCEPTION_TYPE, throwable.getClass().getName());
+      String message = throwable.getMessage();
+      if (message != null) {
+        logRecordBuilder.setAttribute(EXCEPTION_MESSAGE, message);
+      }
+      StringWriter writer = new StringWriter();
+      throwable.printStackTrace(new PrintWriter(writer));
+      logRecordBuilder.setAttribute(EXCEPTION_STACKTRACE, writer.toString());
+    }
+
+    logRecordBuilder.emit();
+  }
+
   private static long getNanos(@Nullable Instant time) {
     if (time == null) {
       return System.nanoTime();