FileSystemLogAppender.java

/*
 * Copyright 2014-2016 CyberVision, Inc.
 *
 * 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 org.kaaproject.kaa.server.appenders.file.appender;

import org.kaaproject.kaa.common.dto.logs.LogAppenderDto;
import org.kaaproject.kaa.common.dto.logs.LogEventDto;
import org.kaaproject.kaa.server.appenders.file.config.gen.FileConfig;
import org.kaaproject.kaa.server.common.log.shared.appender.AbstractLogAppender;
import org.kaaproject.kaa.server.common.log.shared.appender.LogDeliveryCallback;
import org.kaaproject.kaa.server.common.log.shared.appender.LogEventPack;
import org.kaaproject.kaa.server.common.log.shared.avro.gen.RecordHeader;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.nio.file.Paths;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.List;

public class FileSystemLogAppender extends AbstractLogAppender<FileConfig> {

  private static final Logger LOG = LoggerFactory.getLogger(FileSystemLogAppender.class);

  private FileSystemLogEventService fileSystemLogEventService;
  private FileSystemLogger logger;

  private String logsRootPath;

  private String tenantDirName;
  private String applicationDirName;

  private boolean closed = false;

  public FileSystemLogAppender() {
    super(FileConfig.class);
  }

  @Override
  public void doAppend(LogEventPack logEventPack, RecordHeader header,
                       LogDeliveryCallback listener) {
    if (!closed) {
      try {
        String path = logsRootPath + "/" + tenantDirName + "/" + applicationDirName;
        LOG.debug("[{}] appending {} logs to directory", path, logEventPack.getEvents().size());
        List<String> dtos = eventsToStrings(generateLogEvent(logEventPack, header));
        LOG.debug("[{}] saving {} objects", path, dtos.size());
        for (String event : dtos) {
          logger.append(event);
        }
        LOG.debug("[{}] appended {} logs to directory", path, logEventPack.getEvents().size());
        listener.onSuccess();
      } catch (Exception ex) {
        LOG.error(MessageFormat.format("[{0}] Attempted to append logs failed", getName()), ex);
        listener.onInternalError();
      }
    } else {
      LOG.info("Attempted to append to closed appender named [{}].", getName());
      listener.onInternalError();
    }
  }

  private List<String> eventsToStrings(List<LogEventDto> dtos) {
    List<String> events = new ArrayList<>();
    for (LogEventDto logEventDto : dtos) {
      String event = new StringBuilder("{\"Log Header\": \"")
          .append(logEventDto.getHeader())
          .append("\", \"Event\": ")
          .append(logEventDto.getEvent())
          .append("}").toString();
      events.add(event);
    }
    return events;
  }

  @Override
  protected void initFromConfiguration(LogAppenderDto appenderDto, FileConfig configuration) {
    LOG.debug("Initializing new instance of file system log appender");
    try {
      logsRootPath = configuration.getLogsRootPath();
      if (fileSystemLogEventService == null) {
        fileSystemLogEventService = new FileSystemLogEventServiceImpl();
      }
      if (logger == null) {
        logger = new LogbackFileSystemLogger();
      }
      initLogDirectories(appenderDto);
      logger.init(appenderDto, configuration,
          Paths.get(logsRootPath, tenantDirName, applicationDirName, "application.log"));
      fileSystemLogEventService.createUserAndGroup(appenderDto, configuration,
          Paths.get(logsRootPath, tenantDirName, applicationDirName).toAbsolutePath().toString());
    } catch (Exception ex) {
      LOG.error("Failed to init file system log appender: ", ex);
    }
  }

  private void createTenantLogDirectory(String tenantId) {
    tenantDirName = "tenant_" + tenantId;
    fileSystemLogEventService.createDirectory(logsRootPath + "/" + tenantDirName);
  }

  private void createApplicationLogDirectory(String applicationToken) {
    applicationDirName = "application_" + applicationToken;
    fileSystemLogEventService
        .createDirectory(logsRootPath + "/" + tenantDirName + "/" + applicationDirName);
  }

  private void initLogDirectories(LogAppenderDto appender) {
    fileSystemLogEventService.createRootLogDirCommand(logsRootPath);
    createTenantLogDirectory(appender.getTenantId());
    createApplicationLogDirectory(appender.getApplicationToken());
  }

  @Override
  public void close() {
    if (!closed) {
      closed = true;
      if (logger != null) {
        try {
          logger.close();
        } catch (IOException ex) {
          LOG.warn("IO Exception catched: ", ex);
        }
      }
      fileSystemLogEventService = null;
      logger = null;
    }
    LOG.debug("Stoped filesystem log appender.");
  }

}