googleapis · codyoss · Nov 14, 2019 · Oct 2, 2019 · Oct 3, 2019 · Oct 3, 2019
diff --git a/...cloud-logging-logback/src/main/java/com/google/cloud/logging/logback/LoggingAppender.java b/...cloud-logging-logback/src/main/java/com/google/cloud/logging/logback/LoggingAppender.java
@@ -34,13 +34,13 @@
 import com.google.cloud.logging.Payload;
 import com.google.cloud.logging.Severity;
 import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableList;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.List;
-import java.util.Map;
 import java.util.Set;
 
 /**
@@ -72,6 +72,8 @@ public class LoggingAppender extends UnsynchronizedAppenderBase<ILoggingEvent> {
   private static final String LEVEL_NAME_KEY = "levelName";
   private static final String LEVEL_VALUE_KEY = "levelValue";
   private static final String LOGGER_NAME_KEY = "loggerName";
+  private static final List<LoggingEventEnhancer> DEFAULT_LOGGING_EVENT_ENHANCERS =
+      ImmutableList.<LoggingEventEnhancer>of(new MDCEventEnhancer());
 
   private volatile Logging logging;
   private LoggingOptions loggingOptions;
@@ -157,7 +159,11 @@ List<LoggingEnhancer> getLoggingEnhancers() {
   }
 
   List<LoggingEventEnhancer> getLoggingEventEnhancers() {
-    return getEnhancers(loggingEventEnhancerClassNames);
+    if (loggingEventEnhancerClassNames.isEmpty()) {
+      return DEFAULT_LOGGING_EVENT_ENHANCERS;
+    } else {
+      return getEnhancers(loggingEventEnhancerClassNames);
+    }
   }
 
   <T> List<T> getEnhancers(Set<String> classNames) {
@@ -278,12 +284,6 @@ private LogEntry logEntryFor(ILoggingEvent e) {
         .addLabel(LEVEL_VALUE_KEY, String.valueOf(level.toInt()))
         .addLabel(LOGGER_NAME_KEY, e.getLoggerName());
 
-    for (Map.Entry<String, String> entry : e.getMDCPropertyMap().entrySet()) {
-      if (null != entry.getKey() && null != entry.getValue()) {
-        builder.addLabel(entry.getKey(), entry.getValue());
-      }
-    }
-
     if (loggingEnhancers != null) {
       for (LoggingEnhancer enhancer : loggingEnhancers) {
         enhancer.enhanceLogEntry(builder);

diff --git a/...loud-logging-logback/src/main/java/com/google/cloud/logging/logback/MDCEventEnhancer.java b/...loud-logging-logback/src/main/java/com/google/cloud/logging/logback/MDCEventEnhancer.java
@@ -0,0 +1,40 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.cloud.logging.logback;
+
+import ch.qos.logback.classic.spi.ILoggingEvent;
+import com.google.cloud.logging.LogEntry;
+import java.util.Map;
+
+/**
+ * MDCEventEnhancer takes values found in the MDC property map and adds them as labels to the {@link
+ * LogEntry}. This {@link LoggingEventEnhancer} is turned on by default. If you wish to filter which
+ * MDC values get added as labels to your {@link LogEntry}, implement a {@link LoggingEventEnhancer}
+ * and add its classpath to your {@code logback.xml}. If any {@link LoggingEventEnhancer} is added
+ * this class is no longer registered.
+ */
+final class MDCEventEnhancer implements LoggingEventEnhancer {
+
+  @Override
+  public final void enhanceLogEntry(LogEntry.Builder builder, ILoggingEvent e) {
+    for (Map.Entry<String, String> entry : e.getMDCPropertyMap().entrySet()) {
+      if (null != entry.getKey() && null != entry.getValue()) {
+        builder.addLabel(entry.getKey(), entry.getValue());
+      }
+    }
+  }
+}
diff --git a/...d-logging-logback/src/test/java/com/google/cloud/logging/logback/LoggingAppenderTest.java b/...d-logging-logback/src/test/java/com/google/cloud/logging/logback/LoggingAppenderTest.java
@@ -26,6 +26,7 @@
 
 import ch.qos.logback.classic.Level;
 import ch.qos.logback.classic.filter.ThresholdFilter;
+import ch.qos.logback.classic.spi.ILoggingEvent;
 import ch.qos.logback.classic.spi.LoggingEvent;
 import com.google.cloud.MonitoredResource;
 import com.google.cloud.Timestamp;
@@ -48,8 +49,8 @@
 @RunWith(EasyMockRunner.class)
 public class LoggingAppenderTest {
   private final String projectId = "test-project";
-  private final Logging logging = EasyMock.createStrictMock(Logging.class);
-  private LoggingAppender loggingAppender = new TestLoggingAppender();
+  private Logging logging;
+  private LoggingAppender loggingAppender;
 
   class TestLoggingAppender extends LoggingAppender {
     @Override
@@ -64,7 +65,10 @@ Logging getLogging() {
   }
 
   @Before
-  public void setUp() {}
+  public void setUp() {
+    logging = EasyMock.createStrictMock(Logging.class);
+    loggingAppender = new TestLoggingAppender();
+  }
 
   private final WriteOption[] defaultWriteOptions =
       new WriteOption[] {
@@ -277,4 +281,43 @@ public void testMdcValuesAreConvertedToLabelsWithPassingNullValues() {
     assertThat(capturedArgumentMap.get("mdc2")).isNull();
     assertThat(capturedArgumentMap.get("mdc3")).isEqualTo("value3");
   }
+
+  @Test
+  public void testAddCustomLoggingEventEnhancers() {
+    MDC.put("mdc1", "value1");
+    logging.setFlushSeverity(Severity.ERROR);
+    Capture<Iterable<LogEntry>> capturedArgument = Capture.newInstance();
+    logging.write(capture(capturedArgument), (WriteOption) anyObject(), (WriteOption) anyObject());
+    expectLastCall().once();
+    replay(logging);
+    Timestamp timestamp = Timestamp.ofTimeSecondsAndNanos(100000, 0);
+    LoggingEvent loggingEvent = createLoggingEvent(Level.INFO, timestamp.getSeconds());
+    loggingAppender.addLoggingEventEnhancer(CustomLoggingEventEnhancer1.class.getName());
+    loggingAppender.addLoggingEventEnhancer(CustomLoggingEventEnhancer2.class.getName());
+    loggingAppender.start();
+    loggingAppender.doAppend(loggingEvent);
+    verify(logging);
+    MDC.remove("mdc1");
+    Map<String, String> capturedArgumentMap =
+        capturedArgument.getValue().iterator().next().getLabels();
+    assertThat(capturedArgumentMap.get("mdc1")).isNull();
+    assertThat(capturedArgumentMap.get("foo")).isEqualTo("foo");
+    assertThat(capturedArgumentMap.get("bar")).isEqualTo("bar");
+  }
+
+  static class CustomLoggingEventEnhancer1 implements LoggingEventEnhancer {
+
+    @Override
+    public void enhanceLogEntry(LogEntry.Builder builder, ILoggingEvent e) {
+      builder.addLabel("foo", "foo");
+    }
+  }
+
+  static class CustomLoggingEventEnhancer2 implements LoggingEventEnhancer {
+
+    @Override
+    public void enhanceLogEntry(LogEntry.Builder builder, ILoggingEvent e) {
+      builder.addLabel("bar", "bar");
+    }
+  }
 }
diff --git a/...-logging-logback/src/test/java/com/google/cloud/logging/logback/MDCEventEnhancerTest.java b/...-logging-logback/src/test/java/com/google/cloud/logging/logback/MDCEventEnhancerTest.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2019 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.google.cloud.logging.logback;
+
+import static com.google.common.truth.Truth.assertThat;
+
+import ch.qos.logback.classic.spi.LoggingEvent;
+import com.google.cloud.logging.LogEntry;
+import com.google.cloud.logging.Payload.StringPayload;
+import java.util.Collections;
+import org.junit.Before;
+import org.junit.Test;
+
+public class MDCEventEnhancerTest {
+  private MDCEventEnhancer classUnderTest;
+
+  @Before
+  public void setUp() {
+    classUnderTest = new MDCEventEnhancer();
+  }
+
+  @Test
+  public void testEnhanceLogEntry() {
+    LoggingEvent loggingEvent = new LoggingEvent();
+    loggingEvent.setMessage("this is a test");
+    loggingEvent.setMDCPropertyMap(Collections.singletonMap("foo", "bar"));
+    LogEntry.Builder builder = LogEntry.newBuilder(StringPayload.of("this is a test"));
+
+    classUnderTest.enhanceLogEntry(builder, loggingEvent);
+    LogEntry logEntry = builder.build();
+
+    assertThat(logEntry.getLabels().get("foo")).isEqualTo("bar");
+  }
+}