Add Tomcat JULI implementation

Adds a Tomcat JULI implementation that can replace the one in `org.apache.logging.log4:log4j-appserver`. The main differences between this implementation and the official one: * it retrieves the correct logger context by setting `fqcn` to `org.apache.juli.LogFactory` instead of the class name of the logger, * it does not treat the filenames `log4j2-tomcat.*` differently, leaving the configuration entirely to the implementation.
copernik-eu · Jan 28, 2024 · 068c1af · 068c1af
1 parent 561b255
commit 068c1af
Show file tree

Hide file tree

Showing 6 changed files with 336 additions and 0 deletions.
diff --git a/log4j-tomcat-juli/pom.xml b/log4j-tomcat-juli/pom.xml
@@ -0,0 +1,75 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Copyright © 2024 Piotr P. Karwasz
+  ~
+  ~ 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.
+  -->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>eu.copernik</groupId>
+    <artifactId>log4j-plugins-parent</artifactId>
+    <version>3.0.0-SNAPSHOT</version>
+  </parent>
+
+  <groupId>org.apache.logging.log4j</groupId>
+  <artifactId>log4j-tomcat-juli</artifactId>
+  <name>Tomcat JULI to Log4j API bridge</name>
+  <description>Tomcat JULI implementation that forwards to the Log4j API.</description>
+
+  <properties>
+    <bnd.baseline.fail.on.missing>false</bnd.baseline.fail.on.missing>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>biz.aQute.bnd</groupId>
+      <artifactId>biz.aQute.bnd.annotation</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.logging.log4j</groupId>
+      <artifactId>log4j-api</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.tomcat</groupId>
+      <artifactId>tomcat-juli</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.assertj</groupId>
+      <artifactId>assertj-core</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-api</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.logging.log4j</groupId>
+      <artifactId>log4j-api-test</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.logging.log4j</groupId>
+      <artifactId>log4j-core-test</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.mockito</groupId>
+      <artifactId>mockito-core</artifactId>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+</project>
diff --git a/log4j-tomcat-juli/src/main/java/eu/copernik/log4j/tomcat/juli/Log4jLog.java b/log4j-tomcat-juli/src/main/java/eu/copernik/log4j/tomcat/juli/Log4jLog.java
@@ -0,0 +1,143 @@
+/*
+ * Copyright © 2024 Piotr P. Karwasz
+ *
+ * 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 eu.copernik.log4j.tomcat.juli;
+
+import aQute.bnd.annotation.Resolution;
+import aQute.bnd.annotation.spi.ServiceProvider;
+import org.apache.juli.logging.Log;
+import org.apache.juli.logging.LogFactory;
+import org.apache.logging.log4j.Level;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Marker;
+import org.apache.logging.log4j.MarkerManager;
+import org.apache.logging.log4j.spi.ExtendedLogger;
+import org.apache.logging.log4j.spi.LoggerContextFactory;
+
+/**
+ * An implementation of {@link Log} that forwards everything to the appropriate Log4j API logger.
+ */
+@ServiceProvider(value = Log.class, resolution = Resolution.OPTIONAL)
+public class Log4jLog implements Log {
+
+    private static final String FQCN = Log4jLog.class.getName();
+    private static final String LOG_FACTORY_FQCN = LogFactory.class.getName();
+    private static final Marker TOMCAT_MARKER = MarkerManager.getMarker("TOMCAT");
+
+    private ExtendedLogger logger;
+
+    // Only used by ServiceLoader
+    public Log4jLog() {
+        this(LogManager.ROOT_LOGGER_NAME);
+    }
+
+    public Log4jLog(final String name) {
+        this(LogManager.getFactory(), name);
+    }
+
+    Log4jLog(final LoggerContextFactory factory, final String name) {
+        this.logger = factory.getContext(LOG_FACTORY_FQCN, null, null, false).getLogger(name);
+    }
+
+    @Override
+    public boolean isDebugEnabled() {
+        return logger.isDebugEnabled(TOMCAT_MARKER);
+    }
+
+    @Override
+    public boolean isErrorEnabled() {
+        return logger.isDebugEnabled(TOMCAT_MARKER);
+    }
+
+    @Override
+    public boolean isFatalEnabled() {
+        return logger.isFatalEnabled(TOMCAT_MARKER);
+    }
+
+    @Override
+    public boolean isInfoEnabled() {
+        return logger.isInfoEnabled(TOMCAT_MARKER);
+    }
+
+    @Override
+    public boolean isTraceEnabled() {
+        return logger.isTraceEnabled(TOMCAT_MARKER);
+    }
+
+    @Override
+    public boolean isWarnEnabled() {
+        return logger.isWarnEnabled(TOMCAT_MARKER);
+    }
+
+    @Override
+    public void trace(final Object message) {
+        logger.logIfEnabled(FQCN, Level.TRACE, TOMCAT_MARKER, message, null);
+    }
+
+    @Override
+    public void trace(final Object message, final Throwable t) {
+        logger.logIfEnabled(FQCN, Level.TRACE, TOMCAT_MARKER, message, t);
+    }
+
+    @Override
+    public void debug(final Object message) {
+        logger.logIfEnabled(FQCN, Level.DEBUG, TOMCAT_MARKER, message, null);
+    }
+
+    @Override
+    public void debug(final Object message, final Throwable t) {
+        logger.logIfEnabled(FQCN, Level.DEBUG, TOMCAT_MARKER, message, t);
+    }
+
+    @Override
+    public void info(final Object message) {
+        logger.logIfEnabled(FQCN, Level.INFO, TOMCAT_MARKER, message, null);
+    }
+
+    @Override
+    public void info(final Object message, final Throwable t) {
+        logger.logIfEnabled(FQCN, Level.INFO, TOMCAT_MARKER, message, t);
+    }
+
+    @Override
+    public void warn(final Object message) {
+        logger.logIfEnabled(FQCN, Level.WARN, TOMCAT_MARKER, message, null);
+    }
+
+    @Override
+    public void warn(final Object message, final Throwable t) {
+        logger.logIfEnabled(FQCN, Level.WARN, TOMCAT_MARKER, message, t);
+    }
+
+    @Override
+    public void error(final Object message) {
+        logger.logIfEnabled(FQCN, Level.ERROR, TOMCAT_MARKER, message, null);
+    }
+
+    @Override
+    public void error(final Object message, final Throwable t) {
+        logger.logIfEnabled(FQCN, Level.ERROR, TOMCAT_MARKER, message, t);
+    }
+
+    @Override
+    public void fatal(final Object message) {
+        logger.logIfEnabled(FQCN, Level.FATAL, TOMCAT_MARKER, message, null);
+    }
+
+    @Override
+    public void fatal(final Object message, final Throwable t) {
+        logger.logIfEnabled(FQCN, Level.FATAL, TOMCAT_MARKER, message, t);
+    }
+}
diff --git a/log4j-tomcat-juli/src/test/java/Log4jLogTest.java b/log4j-tomcat-juli/src/test/java/Log4jLogTest.java
@@ -0,0 +1,81 @@
+/*
+ * Copyright © 2024 Piotr P. Karwasz
+ *
+ * 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.
+ */
+import static org.assertj.core.api.Assertions.assertThat;
+
+import java.util.List;
+import org.apache.juli.logging.Log;
+import org.apache.juli.logging.LogFactory;
+import org.apache.logging.log4j.Level;
+import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.core.LoggerContext;
+import org.apache.logging.log4j.core.config.Configuration;
+import org.apache.logging.log4j.core.test.appender.ListAppender;
+import org.junit.jupiter.api.Test;
+
+class Log4jLogTest {
+
+    private static final String MESSAGE = "MESSAGE";
+    private static final Throwable T = new RuntimeException();
+
+    @Test
+    void location() {
+        final Log log = LogFactory.getLog("location");
+        int i = 0;
+        int currentLine = 37;
+        log.trace(MESSAGE + i++);
+        log.trace(MESSAGE + i++, T);
+        log.debug(MESSAGE + i++);
+        log.debug(MESSAGE + i++, T);
+        log.info(MESSAGE + i++);
+        log.info(MESSAGE + i++, T);
+        log.warn(MESSAGE + i++);
+        log.warn(MESSAGE + i++, T);
+        log.error(MESSAGE + i++);
+        log.error(MESSAGE + i++, T);
+        log.fatal(MESSAGE + i++);
+        log.fatal(MESSAGE + i, T);
+        // Verification
+        final LoggerContext context = LoggerContext.getContext(false);
+        final Configuration config = context.getConfiguration();
+        final ListAppender list = config.getAppender("list");
+        final List<LogEvent> events = list.getEvents();
+        i = 0;
+        assertThat(events).hasSize(12);
+        assertLocation(events.get(i), Level.TRACE, MESSAGE + i++, null, ++currentLine);
+        assertLocation(events.get(i), Level.TRACE, MESSAGE + i++, T, ++currentLine);
+        assertLocation(events.get(i), Level.DEBUG, MESSAGE + i++, null, ++currentLine);
+        assertLocation(events.get(i), Level.DEBUG, MESSAGE + i++, T, ++currentLine);
+        assertLocation(events.get(i), Level.INFO, MESSAGE + i++, null, ++currentLine);
+        assertLocation(events.get(i), Level.INFO, MESSAGE + i++, T, ++currentLine);
+        assertLocation(events.get(i), Level.WARN, MESSAGE + i++, null, ++currentLine);
+        assertLocation(events.get(i), Level.WARN, MESSAGE + i++, T, ++currentLine);
+        assertLocation(events.get(i), Level.ERROR, MESSAGE + i++, null, ++currentLine);
+        assertLocation(events.get(i), Level.ERROR, MESSAGE + i++, T, ++currentLine);
+        assertLocation(events.get(i), Level.FATAL, MESSAGE + i++, null, ++currentLine);
+        assertLocation(events.get(i), Level.FATAL, MESSAGE + i, T, ++currentLine);
+    }
+
+    private void assertLocation(
+            final LogEvent event, final Level level, final String message, final Throwable t, final int lineNumber) {
+        assertThat(event.getLevel()).isEqualTo(level);
+        assertThat(event.getMessage().getFormattedMessage()).isEqualTo(message);
+        assertThat(event.getThrown()).isEqualTo(t);
+        final StackTraceElement location = event.getSource();
+        assertThat(location.getClassName()).isEqualTo(Log4jLogTest.class.getName());
+        assertThat(location.getMethodName()).isEqualTo("location");
+        assertThat(location.getLineNumber()).isEqualTo(lineNumber);
+    }
+}
diff --git a/log4j-tomcat-juli/src/test/resources/log4j2-test.xml b/log4j-tomcat-juli/src/test/resources/log4j2-test.xml
@@ -0,0 +1,26 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ Copyright © 2024 Piotr P. Karwasz
+  ~
+  ~ 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.
+  -->
+<Configuration status="OFF">
+    <Appenders>
+        <List name="list"/>
+    </Appenders>
+    <Loggers>
+        <Root level="TRACE">
+            <AppenderRef ref="list"/>
+        </Root>
+    </Loggers>
+</Configuration>
diff --git a/pom.xml b/pom.xml
@@ -56,6 +56,7 @@
   <modules>
     <module>log4j-tomcat</module>
     <module>log4j-tomcat-env</module>
+    <module>log4j-tomcat-juli</module>
   </modules>
 
   <scm>

diff --git a/src/changelog/.3.x.x/101_add_tomcat_juli.xml b/src/changelog/.3.x.x/101_add_tomcat_juli.xml
@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<entry xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+       xmlns="http://logging.apache.org/log4j/changelog"
+       xsi:schemaLocation="http://logging.apache.org/log4j/changelog https://logging.apache.org/log4j/changelog-0.1.3.xsd"
+       type="changed">
+  <issue id="101" link="https://github.com/copernik-eu/log4j-plugins/issues/101"/>
+  <description format="asciidoc">
+    Add Tomcat JULI implementation in artifact `log4j-tomcat-juli`.
+  </description>
+</entry>