Add option to provide URIs to monitor in addition to the config file

log4j-core-test/src/test/java/org/apache/logging/log4j/core/MonitorResourcesTest.java

@@ -0,0 +1,123 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to you 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 org.apache.logging.log4j.core;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.awaitility.Awaitility.waitAtMost;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.LinkedHashSet;
+import java.util.Set;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+import org.apache.logging.log4j.core.config.Configuration;
+import org.apache.logging.log4j.core.config.ConfigurationSource;
+import org.apache.logging.log4j.core.config.Configurator;
+import org.apache.logging.log4j.core.config.builder.api.ComponentBuilder;
+import org.apache.logging.log4j.core.config.builder.api.ConfigurationBuilder;
+import org.apache.logging.log4j.core.config.builder.api.ConfigurationBuilderFactory;
+import org.apache.logging.log4j.core.config.properties.PropertiesConfiguration;
+import org.apache.logging.log4j.core.test.junit.LoggerContextSource;
+import org.apache.logging.log4j.core.util.Source;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.CleanupMode;
+import org.junit.jupiter.api.io.TempDir;
+
+public class MonitorResourcesTest {
+
+ @Test
+ void test_reconfiguration(@TempDir(cleanup = CleanupMode.ON_SUCCESS) final Path tempDir) throws IOException {
+ final ConfigurationBuilder<PropertiesConfiguration> configBuilder =
+ ConfigurationBuilderFactory.newConfigurationBuilder(PropertiesConfiguration.class);
+ final Path configFile = tempDir.resolve("log4j.xml");
+ final Path externalResourceFile1 = tempDir.resolve("external-resource-1.txt");
+ final Path externalResourceFile2 = tempDir.resolve("external-resource-2.txt");
+ final ConfigurationSource configSource = new ConfigurationSource(new Source(configFile), new byte[] {}, 0);
+ final int monitorInterval = 3;
+
+ final ComponentBuilder<?> monitorResourcesComponent = configBuilder.newComponent("MonitorResources");
+ monitorResourcesComponent.addComponent(configBuilder
+ .newComponent("MonitorResource")
+ .addAttribute("uri", externalResourceFile1.toUri().toString()));
+ monitorResourcesComponent.addComponent(configBuilder
+ .newComponent("MonitorResource")
+ .addAttribute("uri", externalResourceFile2.toUri().toString()));
+
+ final Configuration config = configBuilder
+ .setConfigurationSource(configSource)
+ .setMonitorInterval(String.valueOf(monitorInterval))
+ .addComponent(monitorResourcesComponent)
+ .build();
+
+ try (final LoggerContext loggerContext = Configurator.initialize(config)) {
+ assertMonitorResourceFileNames(
+ loggerContext,
+ configFile.getFileName().toString(),
+ externalResourceFile1.getFileName().toString(),
+ externalResourceFile2.getFileName().toString());
+ Files.write(externalResourceFile2, Collections.singletonList("a change"));
+ waitAtMost(2 * monitorInterval, TimeUnit.SECONDS).until(() -> loggerContext.getConfiguration() != config);
+ }
+ }
+
+ @Test
+ @LoggerContextSource("config/MonitorResource/log4j.xml")
+ void test_config_of_type_XML(final LoggerContext loggerContext) {
+ assertMonitorResourceFileNames(loggerContext, "log4j.xml");
+ }
+
+ @Test
+ @LoggerContextSource("config/MonitorResource/log4j.json")
+ void test_config_of_type_JSON(final LoggerContext loggerContext) {
+ assertMonitorResourceFileNames(loggerContext, "log4j.json");
+ }
+
+ @Test
+ @LoggerContextSource("config/MonitorResource/log4j.yaml")
+ void test_config_of_type_YAML(final LoggerContext loggerContext) {
+ assertMonitorResourceFileNames(loggerContext, "log4j.yaml");
+ }
+
+ @Test
+ @LoggerContextSource("config/MonitorResource/log4j.properties")
+ void test_config_of_type_properties(final LoggerContext loggerContext) {
+ assertMonitorResourceFileNames(loggerContext, "log4j.properties");
+ }
+
+ private static void assertMonitorResourceFileNames(final LoggerContext loggerContext, final String configFileName) {
+ assertMonitorResourceFileNames(loggerContext, configFileName, "external-file-1.txt", "external-file-2.txt");
+ }
+
+ private static void assertMonitorResourceFileNames(
+ final LoggerContext loggerContext, final String configFileName, final String... externalResourceFileNames) {
+ final Set<Source> sources = loggerContext
+ .getConfiguration()
+ .getWatchManager()
+ .getConfigurationWatchers()
+ .keySet();
+ final Set<String> actualFileNames =
+ sources.stream().map(source -> source.getFile().getName()).collect(Collectors.toSet());
+ final Set<String> expectedFileNames = new LinkedHashSet<>();
+ expectedFileNames.add(configFileName);
+ expectedFileNames.addAll(Arrays.asList(externalResourceFileNames));
+ assertThat(actualFileNames).as("watch manager sources: %s", sources).isEqualTo(expectedFileNames);
+ }
+}

log4j-core-test/src/test/java/org/apache/logging/log4j/core/async/AsyncWaitStrategyFactoryConfigTest.java

@@ -45,6 +45,17 @@ void testConfigWaitStrategyFactory(final LoggerContext context) {
  asyncWaitStrategyFactory instanceof YieldingWaitStrategyFactory);
  }
 
+ @Test
+ @LoggerContextSource("AsyncWaitStrategyFactoryConfigTest.properties")
+ void testConfigWaitStrategyFactoryFromProperties(final LoggerContext context) {
+ final AsyncWaitStrategyFactory asyncWaitStrategyFactory =
+ context.getConfiguration().getAsyncWaitStrategyFactory();
+ assertEquals(YieldingWaitStrategyFactory.class, asyncWaitStrategyFactory.getClass());
+ assertThat(
+ "factory is YieldingWaitStrategyFactory",
+ asyncWaitStrategyFactory instanceof YieldingWaitStrategyFactory);
+ }
+
  @Test
  @LoggerContextSource("AsyncWaitStrategyFactoryConfigTest.xml")
  void testWaitStrategy(final LoggerContext context) {

log4j-core-test/src/test/resources/AsyncWaitStrategyFactoryConfigTest.properties

@@ -0,0 +1,19 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to you 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.
+#
+
+strategy.type = AsyncWaitStrategyFactory
+strategy.class = org.apache.logging.log4j.core.async.AsyncWaitStrategyFactoryConfigTest$YieldingWaitStrategyFactory

log4j-core-test/src/test/resources/config/MonitorResource/log4j.json

@@ -0,0 +1,15 @@
+{
+ "Configuration": {
+ "monitorInterval": "30",
+ "MonitorResources": {
+ "MonitorResource": [
+ {
+ "uri": "file://path/to/external-file-1.txt"
+ },
+ {
+ "uri": "file://path/to/external-file-2.txt"
+ }
+ ]
+ }
+ }
+}

log4j-core-test/src/test/resources/config/MonitorResource/log4j.properties

@@ -0,0 +1,22 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to you 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.
+#
+monitorInterval = 30
+monitorResources.type = MonitorResources
+monitorResources.0.type = MonitorResource
+monitorResources.0.uri = file://path/to/external-file-1.txt
+monitorResources.1.type = MonitorResource
+monitorResources.1.uri = file://path/to/external-file-2.txt

log4j-core-test/src/test/resources/config/MonitorResource/log4j.xml

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ ~ Licensed to the Apache Software Foundation (ASF) under one or more
+ ~ contributor license agreements. See the NOTICE file distributed with
+ ~ this work for additional information regarding copyright ownership.
+ ~ The ASF licenses this file to you 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 xmlns="https://logging.apache.org/xml/ns"
+ xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+ xsi:schemaLocation="
+ https://logging.apache.org/xml/ns
+ https://logging.apache.org/xml/ns/log4j-config-2.xsd"
+ monitorInterval="30">
+ <MonitorResources>
+ <MonitorResource uri="file://path/to/external-file-1.txt"/>
+ <MonitorResource uri="file://path/to/external-file-2.txt"/>
+ </MonitorResources>
+</Configuration>

log4j-core-test/src/test/resources/config/MonitorResource/log4j.yaml

@@ -0,0 +1,22 @@
+#
+# Licensed to the Apache Software Foundation (ASF) under one or more
+# contributor license agreements. See the NOTICE file distributed with
+# this work for additional information regarding copyright ownership.
+# The ASF licenses this file to you 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:
+ monitorInterval: '30'
+ MonitorResources:
+ MonitorResource:
+ - uri: "file://path/to/external-file-1.txt"
+ - uri: "file://path/to/external-file-2.txt"

log4j-core/src/main/java/org/apache/logging/log4j/core/config/AbstractConfiguration.java

@@ -132,6 +132,7 @@ public abstract class AbstractConfiguration extends AbstractFilterable implement
  private ConcurrentMap<String, Appender> appenders = new ConcurrentHashMap<>();
  private ConcurrentMap<String, LoggerConfig> loggerConfigs = new ConcurrentHashMap<>();
  private List<CustomLevelConfig> customLevels = Collections.emptyList();
+ private Set<MonitorResource> monitorResources = Collections.emptySet();
  private final ConcurrentMap<String, String> propertyMap = new ConcurrentHashMap<>();
  private final Interpolator tempLookup = new Interpolator(propertyMap);
  private final StrSubstitutor runtimeStrSubstitutor = new RuntimeStrSubstitutor(tempLookup);
@@ -267,6 +268,7 @@ public void initialize() {
  setup();
  setupAdvertisement();
  doConfigure();
+ watchMonitorResources();
  setState(State.INITIALIZED);
  LOGGER.debug("Configuration {} initialized", this);
  }
@@ -322,10 +324,10 @@ public void start() {
  }
  LOGGER.info("Starting configuration {}...", this);
  this.setStarting();
- if (watchManager.getIntervalSeconds() >= 0) {
+ if (isConfigurationMonitoringEnabled()) {
  LOGGER.info(
  "Start watching for changes to {} every {} seconds",
- getConfigurationSource(),
+ watchManager.getConfigurationWatchers().keySet(),
  watchManager.getIntervalSeconds());
  watchManager.start();
  }
@@ -347,6 +349,21 @@ public void start() {
  LOGGER.info("Configuration {} started.", this);
  }
 
+ private boolean isConfigurationMonitoringEnabled() {
+ return this instanceof Reconfigurable && watchManager.getIntervalSeconds() > 0;
+ }
+
+ private void watchMonitorResources() {
+ if (isConfigurationMonitoringEnabled()) {
+ monitorResources.forEach(monitorResource -> {
+ Source source = new Source(monitorResource.getUri());
+ final ConfigurationFileWatcher watcher = new ConfigurationFileWatcher(
+ this, (Reconfigurable) this, listeners, source.getFile().lastModified());
+ watchManager.watch(source, watcher);
+ });
+ }
+ }
+
  private boolean hasAsyncLoggers() {
  if (root instanceof AsyncLoggerConfig) {
  return true;
@@ -729,9 +746,16 @@ protected void doConfigure() {
  } else if (child.isInstanceOf(AsyncWaitStrategyFactoryConfig.class)) {
  final AsyncWaitStrategyFactoryConfig awsfc = child.getObject(AsyncWaitStrategyFactoryConfig.class);
  asyncWaitStrategyFactory = awsfc.createWaitStrategyFactory();
+ } else if (child.isInstanceOf(MonitorResources.class)) {
+ monitorResources = child.getObject(MonitorResources.class).getResources();
  } else {
  final List<String> expected = Arrays.asList(
- "\"Appenders\"", "\"Loggers\"", "\"Properties\"", "\"Scripts\"", "\"CustomLevels\"");
+ "\"Appenders\"",
+ "\"Loggers\"",
+ "\"Properties\"",
+ "\"Scripts\"",
+ "\"CustomLevels\"",
+ "\"MonitorResources\"");
  LOGGER.error(
  "Unknown object \"{}\" of type {} is ignored: try nesting it inside one of: {}.",
  child.getName(),