java-design-patterns/publish-subscribe/src/test/java/com/iluwatar/publish/subscribe/LoggerExtension.java

/*
 * This project is licensed under the MIT license. Module model-view-viewmodel is using ZK framework licensed under LGPL (see lgpl-3.0.txt).
 *
 * The MIT License
 * Copyright © 2014-2022 Ilkka Seppälä
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.iluwatar.publish.subscribe;

import ch.qos.logback.classic.Logger;
import ch.qos.logback.classic.spi.ILoggingEvent;
import ch.qos.logback.core.read.ListAppender;
import java.util.List;
import org.junit.jupiter.api.extension.AfterEachCallback;
import org.junit.jupiter.api.extension.BeforeEachCallback;
import org.junit.jupiter.api.extension.ExtensionContext;
import org.slf4j.LoggerFactory;

public class LoggerExtension implements BeforeEachCallback, AfterEachCallback {

  private final ListAppender<ILoggingEvent> listAppender = new ListAppender<>();
  private final Logger logger = (Logger) LoggerFactory.getLogger(Logger.ROOT_LOGGER_NAME);

  @Override
  public void afterEach(ExtensionContext extensionContext) throws Exception {
    listAppender.stop();
    listAppender.list.clear();
    logger.detachAppender(listAppender);
  }

  @Override
  public void beforeEach(ExtensionContext extensionContext) throws Exception {
    logger.addAppender(listAppender);
    listAppender.start();
  }

  public List<String> getMessages() {
    return listAppender.list.stream().map(e -> e.getMessage()).toList();
  }

  public List<String> getFormattedMessages() {
    return listAppender.list.stream().map(e -> e.getFormattedMessage()).toList();
  }
}