[baggage-processor] Add BaggageLogRecordProcessor (#1576)

Co-authored-by: Gregor Zeitlinger <[email protected]>

Author: cyrille-leclerc

baggage-processor/README.md

@@ -1,55 +1,63 @@
 # OpenTelemetry Baggage Span Processor
 
-The BaggageSpanProcessor reads entries stored in Baggage from the parent context
-and adds the baggage keys and values to the `Span` as attributes on start.
+The `BaggageSpanProcessor` and `BaggageLogRecordPRocessor` read entries stored in Baggage from the
+parent context and adds the baggage keys and values to the `Span`, respectively `LogRecord`, as
+attributes on start, respectively emit.
 
-Add this span processor to a tracer provider.
+Add these span and log processors to the tracer and logger providers.
 
 Warning!
 
 To repeat: a consequence of adding data to Baggage is that the keys and values
-will appear in all outgoing trace context headers from the application.
+will appear in all outgoing trace and log context headers from the application.
 
 Do not put sensitive information in Baggage.
 
 ## Usage
 
-Add the span processor when configuring the tracer provider.
+Add the span and log processor when configuring the tracer and logger providers.
 
-To configure the span processor to copy all baggage entries during configuration:
+To configure the span and log processors to copy all baggage entries during configuration:
 
 ```java
 import io.opentelemetry.contrib.baggage.processor;
 // ...
 
-Tracer tracer = SdkTracerProvider.builder()
-  .addSpanProcessor(new BaggageSpanProcessor(BaggageSpanProcessor.allowAllBaggageKeys))
-  .build()
+TracerProvider tracerProvider = SdkTracerProvider.builder()
+    .addSpanProcessor(BaggageSpanProcessor.allowAllBaggageKeys())
+    .build();
+
+LoggerProvider loggerProvider = SdkLoggerProvider.builder()
+    .addLogRecordProcessor(BaggageLogRecordProcessor.allowAllBaggageKeys())
+    .build();
 ```
 
 Alternatively, you can provide a custom baggage key predicate to select which baggage keys you want to copy.
 
 For example, to only copy baggage entries that start with `my-key`:
 
 ```java
-new BaggageSpanProcessor(baggageKey -> baggageKey.startsWith("my-key"))
+new BaggageSpanProcessor(baggageKey -> baggageKey.startsWith("my-key"));
+new BaggageLogRecordProcessor(baggageKey -> baggageKey.startsWith("my-key"));
 ```
 
 For example, to only copy baggage entries that match the regex `^key.+`:
 
 ```java
 Pattern pattern = Pattern.compile("^key.+");
-new BaggageSpanProcessor(baggageKey -> pattern.matcher(baggageKey).matches())
+new BaggageSpanProcessor(baggageKey -> pattern.matcher(baggageKey).matches());
+new BaggageLogRecordProcessor(baggageKey -> pattern.matcher(baggageKey).matches());
 ```
 
 ## Usage with SDK auto-configuration
 
-If you are using the OpenTelemetry SDK auto-configuration, you can add the span processor this
-library to configure the span processor.
+If you are using the OpenTelemetry SDK auto-configuration, you can add the span and log baggage
+processors through configuration.
 
-| Property                                                         | Description                                                                                       |
-|------------------------------------------------------------------|---------------------------------------------------------------------------------------------------|
-| otel.java.experimental.span-attributes.copy-from-baggage.include | Add baggage entries as span attributes, e.g. `key1,key2` or `*` to add all baggage items as keys. |
+| Property                                                           | Description                                                                                       |
+|--------------------------------------------------------------------|---------------------------------------------------------------------------------------------------|
+| `otel.java.experimental.span-attributes.copy-from-baggage.include` | Add baggage entries as span attributes, e.g. `key1,key2` or `*` to add all baggage items as keys. |
+| `otel.java.experimental.log-attributes.copy-from-baggage.include`  | Add baggage entries as log attributes, e.g. `key1,key2` or `*` to add all baggage items as keys.  |
 
 ## Component owners
 

baggage-processor/src/main/java/io/opentelemetry/contrib/baggage/processor/BaggageLogRecordProcessor.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.contrib.baggage.processor;
+
+import io.opentelemetry.api.baggage.Baggage;
+import io.opentelemetry.api.common.AttributeKey;
+import io.opentelemetry.context.Context;
+import io.opentelemetry.sdk.logs.LogRecordProcessor;
+import io.opentelemetry.sdk.logs.ReadWriteLogRecord;
+import java.util.function.Predicate;
+
+/**
+ * This log record processor copies attributes stored in {@link Baggage} into each newly created log
+ * record.
+ */
+public class BaggageLogRecordProcessor implements LogRecordProcessor {
+
+  /**
+   * Creates a new {@link BaggageLogRecordProcessor} that copies all baggage entries into the newly
+   * created log record.
+   */
+  public static BaggageLogRecordProcessor allowAllBaggageKeys() {
+    return new BaggageLogRecordProcessor(baggageKey -> true);
+  }
+
+  private final Predicate<String> baggageKeyPredicate;
+
+  /**
+   * Creates a new {@link BaggageLogRecordProcessor} that copies only baggage entries with keys that
+   * pass the provided filter into the newly created log record.
+   */
+  public BaggageLogRecordProcessor(Predicate<String> baggageKeyPredicate) {
+    this.baggageKeyPredicate = baggageKeyPredicate;
+  }
+
+  @Override
+  public void onEmit(Context context, ReadWriteLogRecord logRecord) {
+    Baggage.fromContext(context)
+        .forEach(
+            (s, baggageEntry) -> {
+              if (baggageKeyPredicate.test(s)) {
+                logRecord.setAttribute(AttributeKey.stringKey(s), baggageEntry.getValue());
+              }
+            });
+  }
+}

baggage-processor/src/main/java/io/opentelemetry/contrib/baggage/processor/BaggageProcessorCustomizer.java

@@ -0,0 +1,68 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.contrib.baggage.processor;
+
+import io.opentelemetry.sdk.autoconfigure.spi.AutoConfigurationCustomizer;
+import io.opentelemetry.sdk.autoconfigure.spi.AutoConfigurationCustomizerProvider;
+import io.opentelemetry.sdk.autoconfigure.spi.ConfigProperties;
+import io.opentelemetry.sdk.logs.SdkLoggerProviderBuilder;
+import io.opentelemetry.sdk.trace.SdkTracerProviderBuilder;
+import java.util.List;
+
+public class BaggageProcessorCustomizer implements AutoConfigurationCustomizerProvider {
+  @Override
+  public void customize(AutoConfigurationCustomizer autoConfigurationCustomizer) {
+    autoConfigurationCustomizer
+        .addTracerProviderCustomizer(
+            (sdkTracerProviderBuilder, config) -> {
+              addSpanProcessor(sdkTracerProviderBuilder, config);
+              return sdkTracerProviderBuilder;
+            })
+        .addLoggerProviderCustomizer(
+            (sdkLoggerProviderBuilder, config) -> {
+              addLogRecordProcessor(sdkLoggerProviderBuilder, config);
+              return sdkLoggerProviderBuilder;
+            });
+  }
+
+  private static void addSpanProcessor(
+      SdkTracerProviderBuilder sdkTracerProviderBuilder, ConfigProperties config) {
+    List<String> keys =
+        config.getList("otel.java.experimental.span-attributes.copy-from-baggage.include");
+
+    if (keys.isEmpty()) {
+      return;
+    }
+
+    sdkTracerProviderBuilder.addSpanProcessor(createBaggageSpanProcessor(keys));
+  }
+
+  static BaggageSpanProcessor createBaggageSpanProcessor(List<String> keys) {
+    if (keys.size() == 1 && keys.get(0).equals("*")) {
+      return BaggageSpanProcessor.allowAllBaggageKeys();
+    }
+    return new BaggageSpanProcessor(keys::contains);
+  }
+
+  private static void addLogRecordProcessor(
+      SdkLoggerProviderBuilder sdkLoggerProviderBuilder, ConfigProperties config) {
+    List<String> keys =
+        config.getList("otel.java.experimental.log-attributes.copy-from-baggage.include");
+
+    if (keys.isEmpty()) {
+      return;
+    }
+
+    sdkLoggerProviderBuilder.addLogRecordProcessor(createBaggageLogRecordProcessor(keys));
+  }
+
+  static BaggageLogRecordProcessor createBaggageLogRecordProcessor(List<String> keys) {
+    if (keys.size() == 1 && keys.get(0).equals("*")) {
+      return BaggageLogRecordProcessor.allowAllBaggageKeys();
+    }
+    return new BaggageLogRecordProcessor(keys::contains);
+  }
+}

baggage-processor/src/main/java/io/opentelemetry/contrib/baggage/processor/BaggageSpanProcessorCustomizer.java

@@ -1 +1 @@
-io.opentelemetry.contrib.baggage.processor.BaggageSpanProcessorCustomizer
+io.opentelemetry.contrib.baggage.processor.BaggageProcessorCustomizer