Configurable exception.* attribute resolution (#7266)

Author: jack-berg

sdk/common/src/main/java/io/opentelemetry/sdk/internal/AttributeUtil.java

@@ -8,12 +8,9 @@
 import io.opentelemetry.api.common.AttributeKey;
 import io.opentelemetry.api.common.Attributes;
 import io.opentelemetry.api.common.AttributesBuilder;
-import java.io.PrintWriter;
-import java.io.StringWriter;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
-import java.util.function.BiConsumer;
 import java.util.function.Predicate;
 
 /**
@@ -22,13 +19,6 @@
  */
 public final class AttributeUtil {
 
-  private static final AttributeKey<String> EXCEPTION_TYPE =
-      AttributeKey.stringKey("exception.type");
-  private static final AttributeKey<String> EXCEPTION_MESSAGE =
-      AttributeKey.stringKey("exception.message");
-  private static final AttributeKey<String> EXCEPTION_STACKTRACE =
-      AttributeKey.stringKey("exception.stacktrace");
-
   private AttributeUtil() {}
 
   /**
@@ -105,26 +95,4 @@ public static Object applyAttributeLengthLimit(Object value, int lengthLimit) {
     }
     return value;
   }
-
-  public static void addExceptionAttributes(
-      Throwable exception, BiConsumer<AttributeKey<String>, String> attributeConsumer) {
-    String exceptionType = exception.getClass().getCanonicalName();
-    if (exceptionType != null) {
-      attributeConsumer.accept(EXCEPTION_TYPE, exceptionType);
-    }
-
-    String exceptionMessage = exception.getMessage();
-    if (exceptionMessage != null) {
-      attributeConsumer.accept(EXCEPTION_MESSAGE, exceptionMessage);
-    }
-
-    StringWriter stringWriter = new StringWriter();
-    try (PrintWriter printWriter = new PrintWriter(stringWriter)) {
-      exception.printStackTrace(printWriter);
-    }
-    String stackTrace = stringWriter.toString();
-    if (stackTrace != null) {
-      attributeConsumer.accept(EXCEPTION_STACKTRACE, stackTrace);
-    }
-  }
 }

sdk/common/src/main/java/io/opentelemetry/sdk/internal/AttributesMap.java

@@ -21,8 +21,8 @@
  * <p>WARNING: In order to reduce memory allocation, this class extends {@link HashMap} when it
  * would be more appropriate to delegate. The problem with extending is that we don't enforce that
  * all {@link HashMap} methods for reading / writing data conform to the configured attribute
- * limits. Therefore, it's easy to accidentally call something like {@link Map#putAll(Map)} or
- * {@link Map#put(Object, Object)} and bypass the restrictions (see <a
+ * limits. Therefore, it's easy to accidentally call something like {@link Map#putAll(Map)} and
+ * bypass the restrictions (see <a
  * href="https://github.com/open-telemetry/opentelemetry-java/issues/7135">#7135</a>). Callers MUST
  * take care to only call methods from {@link AttributesMap}, and not {@link HashMap}.
  *
@@ -58,14 +58,22 @@ public static AttributesMap create(long capacity, int lengthLimit) {
    */
   @Override
   @Nullable
-  public Object put(AttributeKey<?> key, Object value) {
+  public Object put(AttributeKey<?> key, @Nullable Object value) {
+    if (value == null) {
+      return null;
+    }
     totalAddedValues++;
     if (size() >= capacity && !containsKey(key)) {
       return null;
     }
     return super.put(key, AttributeUtil.applyAttributeLengthLimit(value, lengthLimit));
   }
 
+  /** Generic overload of {@link #put(AttributeKey, Object)}. */
+  public <T> void putIfCapacity(AttributeKey<T> key, @Nullable T value) {
+    put(key, value);
+  }
+
   /** Get the total number of attributes added, including those dropped for capacity limits. */
   public int getTotalAddedValues() {
     return totalAddedValues;

sdk/common/src/main/java/io/opentelemetry/sdk/internal/DefaultExceptionAttributeResolver.java

@@ -0,0 +1,50 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.sdk.internal;
+
+import java.io.PrintWriter;
+import java.io.StringWriter;
+
+/**
+ * This class is internal and experimental. Its APIs are unstable and can change at any time. Its
+ * APIs (or a version of them) may be promoted to the public stable API in the future, but no
+ * guarantees are made.
+ */
+public final class DefaultExceptionAttributeResolver implements ExceptionAttributeResolver {
+
+  private static final DefaultExceptionAttributeResolver INSTANCE =
+      new DefaultExceptionAttributeResolver();
+
+  private DefaultExceptionAttributeResolver() {}
+
+  public static ExceptionAttributeResolver getInstance() {
+    return INSTANCE;
+  }
+
+  @Override
+  public void setExceptionAttributes(
+      AttributeSetter attributeSetter, Throwable throwable, int maxAttributeLength) {
+    String exceptionType = throwable.getClass().getCanonicalName();
+    if (exceptionType != null) {
+      attributeSetter.setAttribute(ExceptionAttributeResolver.EXCEPTION_TYPE, exceptionType);
+    }
+
+    String exceptionMessage = throwable.getMessage();
+    if (exceptionMessage != null) {
+      attributeSetter.setAttribute(ExceptionAttributeResolver.EXCEPTION_MESSAGE, exceptionMessage);
+    }
+
+    StringWriter stringWriter = new StringWriter();
+    try (PrintWriter printWriter = new PrintWriter(stringWriter)) {
+      throwable.printStackTrace(printWriter);
+    }
+    String exceptionStacktrace = stringWriter.toString();
+    if (exceptionStacktrace != null) {
+      attributeSetter.setAttribute(
+          ExceptionAttributeResolver.EXCEPTION_STACKTRACE, exceptionStacktrace);
+    }
+  }
+}

sdk/common/src/main/java/io/opentelemetry/sdk/internal/ExceptionAttributeResolver.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.sdk.internal;
+
+import io.opentelemetry.api.common.AttributeKey;
+import javax.annotation.Nullable;
+
+/**
+ * Implementations resolve {@code exception.*} attributes attached to span events, logs, etc.
+ *
+ * <p>This class is internal and experimental. Its APIs are unstable and can change at any time. Its
+ * APIs (or a version of them) may be promoted to the public stable API in the future, but no
+ * guarantees are made.
+ */
+public interface ExceptionAttributeResolver {
+
+  AttributeKey<String> EXCEPTION_TYPE = AttributeKey.stringKey("exception.type");
+  AttributeKey<String> EXCEPTION_MESSAGE = AttributeKey.stringKey("exception.message");
+  AttributeKey<String> EXCEPTION_STACKTRACE = AttributeKey.stringKey("exception.stacktrace");
+
+  void setExceptionAttributes(
+      AttributeSetter attributeSetter, Throwable throwable, int maxAttributeLength);
+
+  /**
+   * This class is internal and experimental. Its APIs are unstable and can change at any time. Its
+   * APIs (or a version of them) may be promoted to the public stable API in the future, but no
+   * guarantees are made.
+   */
+  // TODO(jack-berg): Consider promoting to opentelemetry and extending with Span, LogRecordBuilder,
+  // AttributeBuilder, AttributesMap etc.
+  interface AttributeSetter {
+    <T> void setAttribute(AttributeKey<T> key, @Nullable T value);
+  }
+}

sdk/common/src/main/java/io/opentelemetry/sdk/internal/ExtendedAttributesMap.java

@@ -49,14 +49,23 @@ public static ExtendedAttributesMap create(long capacity, int lengthLimit) {
   }
 
   /** Add the attribute key value pair, applying capacity and length limits. */
-  public <T> void put(ExtendedAttributeKey<T> key, T value) {
+  @Override
+  @Nullable
+  public Object put(ExtendedAttributeKey<?> key, @Nullable Object value) {
+    if (value == null) {
+      return null;
+    }
     totalAddedValues++;
-    // TODO(jack-berg): apply capcity to nested entries
+    // TODO(jack-berg): apply capacity to nested entries
     if (size() >= capacity && !containsKey(key)) {
-      return;
+      return null;
     }
     // TODO(jack-berg): apply limits to nested entries
-    super.put(key, AttributeUtil.applyAttributeLengthLimit(value, lengthLimit));
+    return super.put(key, AttributeUtil.applyAttributeLengthLimit(value, lengthLimit));
+  }
+
+  public <T> void putIfCapacity(ExtendedAttributeKey<T> key, @Nullable T value) {
+    put(key, value);
   }
 
   /**

sdk/logs/src/main/java/io/opentelemetry/sdk/logs/ExtendedSdkLogRecordBuilder.java

@@ -13,7 +13,6 @@
 import io.opentelemetry.api.trace.Span;
 import io.opentelemetry.context.Context;
 import io.opentelemetry.sdk.common.InstrumentationScopeInfo;
-import io.opentelemetry.sdk.internal.AttributeUtil;
 import io.opentelemetry.sdk.internal.ExtendedAttributesMap;
 import java.time.Instant;
 import java.util.concurrent.TimeUnit;
@@ -42,7 +41,12 @@ public ExtendedSdkLogRecordBuilder setException(Throwable throwable) {
       return this;
     }
 
-    AttributeUtil.addExceptionAttributes(throwable, this::setAttribute);
+    loggerSharedState
+        .getExceptionAttributeResolver()
+        .setExceptionAttributes(
+            this::setAttribute,
+            throwable,
+            loggerSharedState.getLogLimits().getMaxAttributeValueLength());
 
     return this;
   }

sdk/logs/src/main/java/io/opentelemetry/sdk/logs/LoggerSharedState.java

@@ -7,6 +7,7 @@
 
 import io.opentelemetry.sdk.common.Clock;
 import io.opentelemetry.sdk.common.CompletableResultCode;
+import io.opentelemetry.sdk.internal.ExceptionAttributeResolver;
 import io.opentelemetry.sdk.resources.Resource;
 import java.util.function.Supplier;
 import javax.annotation.Nullable;
@@ -21,17 +22,20 @@ final class LoggerSharedState {
   private final Supplier<LogLimits> logLimitsSupplier;
   private final LogRecordProcessor logRecordProcessor;
   private final Clock clock;
+  private final ExceptionAttributeResolver exceptionAttributeResolver;
   @Nullable private volatile CompletableResultCode shutdownResult = null;
 
   LoggerSharedState(
       Resource resource,
       Supplier<LogLimits> logLimitsSupplier,
       LogRecordProcessor logRecordProcessor,
-      Clock clock) {
+      Clock clock,
+      ExceptionAttributeResolver exceptionAttributeResolver) {
     this.resource = resource;
     this.logLimitsSupplier = logLimitsSupplier;
     this.logRecordProcessor = logRecordProcessor;
     this.clock = clock;
+    this.exceptionAttributeResolver = exceptionAttributeResolver;
   }
 
   Resource getResource() {
@@ -50,6 +54,10 @@ Clock getClock() {
     return clock;
   }
 
+  ExceptionAttributeResolver getExceptionAttributeResolver() {
+    return exceptionAttributeResolver;
+  }
+
   boolean hasBeenShutdown() {
     return shutdownResult != null;
   }

sdk/logs/src/main/java/io/opentelemetry/sdk/logs/SdkLoggerProvider.java

@@ -13,6 +13,7 @@
 import io.opentelemetry.sdk.common.CompletableResultCode;
 import io.opentelemetry.sdk.common.InstrumentationScopeInfo;
 import io.opentelemetry.sdk.internal.ComponentRegistry;
+import io.opentelemetry.sdk.internal.ExceptionAttributeResolver;
 import io.opentelemetry.sdk.internal.ScopeConfigurator;
 import io.opentelemetry.sdk.logs.internal.LoggerConfig;
 import io.opentelemetry.sdk.resources.Resource;
@@ -56,10 +57,12 @@ public static SdkLoggerProviderBuilder builder() {
       Supplier<LogLimits> logLimitsSupplier,
       List<LogRecordProcessor> processors,
       Clock clock,
-      ScopeConfigurator<LoggerConfig> loggerConfigurator) {
+      ScopeConfigurator<LoggerConfig> loggerConfigurator,
+      ExceptionAttributeResolver exceptionAttributeResolver) {
     LogRecordProcessor logRecordProcessor = LogRecordProcessor.composite(processors);
     this.sharedState =
-        new LoggerSharedState(resource, logLimitsSupplier, logRecordProcessor, clock);
+        new LoggerSharedState(
+            resource, logLimitsSupplier, logRecordProcessor, clock, exceptionAttributeResolver);
     this.loggerComponentRegistry =
         new ComponentRegistry<>(
             instrumentationScopeInfo ->

sdk/logs/src/main/java/io/opentelemetry/sdk/logs/SdkLoggerProviderBuilder.java

@@ -12,6 +12,8 @@
 import io.opentelemetry.context.Context;
 import io.opentelemetry.sdk.common.Clock;
 import io.opentelemetry.sdk.common.InstrumentationScopeInfo;
+import io.opentelemetry.sdk.internal.DefaultExceptionAttributeResolver;
+import io.opentelemetry.sdk.internal.ExceptionAttributeResolver;
 import io.opentelemetry.sdk.internal.ScopeConfigurator;
 import io.opentelemetry.sdk.internal.ScopeConfiguratorBuilder;
 import io.opentelemetry.sdk.logs.data.LogRecordData;
@@ -37,6 +39,8 @@ public final class SdkLoggerProviderBuilder {
   private Clock clock = Clock.getDefault();
   private ScopeConfiguratorBuilder<LoggerConfig> loggerConfiguratorBuilder =
       LoggerConfig.configuratorBuilder();
+  private ExceptionAttributeResolver exceptionAttributeResolver =
+      DefaultExceptionAttributeResolver.getInstance();
 
   SdkLoggerProviderBuilder() {}
 
@@ -168,13 +172,33 @@ SdkLoggerProviderBuilder addLoggerConfiguratorCondition(
     return this;
   }
 
+  /**
+   * Set the exception attribute resolver, which resolves {@code exception.*} attributes an
+   * exception is set on a log.
+   *
+   * <p>This method is experimental so not public. You may reflectively call it using {@link
+   * SdkLoggerProviderUtil#setExceptionAttributeResolver(SdkLoggerProviderBuilder,
+   * ExceptionAttributeResolver)}.
+   */
+  SdkLoggerProviderBuilder setExceptionAttributeResolver(
+      ExceptionAttributeResolver exceptionAttributeResolver) {
+    requireNonNull(exceptionAttributeResolver, "exceptionAttributeResolver");
+    this.exceptionAttributeResolver = exceptionAttributeResolver;
+    return this;
+  }
+
   /**
    * Create a {@link SdkLoggerProvider} instance.
    *
    * @return an instance configured with the provided options
    */
   public SdkLoggerProvider build() {
     return new SdkLoggerProvider(
-        resource, logLimitsSupplier, logRecordProcessors, clock, loggerConfiguratorBuilder.build());
+        resource,
+        logLimitsSupplier,
+        logRecordProcessors,
+        clock,
+        loggerConfiguratorBuilder.build(),
+        exceptionAttributeResolver);
   }
 }

sdk/logs/src/main/java/io/opentelemetry/sdk/logs/internal/SdkLoggerProviderUtil.java

@@ -6,6 +6,7 @@
 package io.opentelemetry.sdk.logs.internal;
 
 import io.opentelemetry.sdk.common.InstrumentationScopeInfo;
+import io.opentelemetry.sdk.internal.ExceptionAttributeResolver;
 import io.opentelemetry.sdk.internal.ScopeConfigurator;
 import io.opentelemetry.sdk.logs.SdkLoggerProvider;
 import io.opentelemetry.sdk.logs.SdkLoggerProviderBuilder;
@@ -73,4 +74,20 @@ public static SdkLoggerProviderBuilder addLoggerConfiguratorCondition(
     }
     return sdkLoggerProviderBuilder;
   }
+
+  /** Reflectively set exception attribute resolver to the {@link SdkLoggerProviderBuilder}. */
+  public static void setExceptionAttributeResolver(
+      SdkLoggerProviderBuilder sdkLoggerProviderBuilder,
+      ExceptionAttributeResolver exceptionAttributeResolver) {
+    try {
+      Method method =
+          SdkLoggerProviderBuilder.class.getDeclaredMethod(
+              "setExceptionAttributeResolver", ExceptionAttributeResolver.class);
+      method.setAccessible(true);
+      method.invoke(sdkLoggerProviderBuilder, exceptionAttributeResolver);
+    } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException e) {
+      throw new IllegalStateException(
+          "Error calling setExceptionAttributeResolver on SdkLoggerProviderBuilder", e);
+    }
+  }
 }