code: /*
   * 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.skywalking.oap.server.core.alarm.provider;
  
  import java.io.FileNotFoundException;
  import java.io.Reader;
  import org.apache.skywalking.oap.server.configuration.api.ConfigurationModule;
  import org.apache.skywalking.oap.server.configuration.api.DynamicConfigurationService;
  import org.apache.skywalking.oap.server.core.CoreModule;
  import org.apache.skywalking.oap.server.core.alarm.AlarmModule;
  import org.apache.skywalking.oap.server.core.alarm.AlarmStandardPersistence;
  import org.apache.skywalking.oap.server.core.alarm.MetricsNotify;
  import org.apache.skywalking.oap.server.library.module.ModuleDefine;
  import org.apache.skywalking.oap.server.library.module.ModuleProvider;
  import org.apache.skywalking.oap.server.library.module.ModuleStartException;
  import org.apache.skywalking.oap.server.library.module.ServiceNotProvidedException;
  import org.apache.skywalking.oap.server.library.util.ResourceUtils;
  
  public class AlarmModuleProvider extends ModuleProvider {
  
      private NotifyHandler notifyHandler;
      private AlarmRulesWatcher alarmRulesWatcher;
  
      @Override
      public String name() {
          return "default";
      }
  
      @Override
      public Class<? extends ModuleDefine> module() {
          return AlarmModule.class;
      }
  
      @Override
      public ConfigCreator newConfigCreator() {
          return null;
      }
  
      @Override
      public void prepare() throws ServiceNotProvidedException, ModuleStartException {
          Reader applicationReader;
          try {
              applicationReader = ResourceUtils.read("alarm-settings.yml");
          } catch (FileNotFoundException e) {
              throw new ModuleStartException("can't load alarm-settings.yml", e);
          }
          RulesReader reader = new RulesReader(applicationReader);
          Rules rules = reader.readRules();
  
          alarmRulesWatcher = new AlarmRulesWatcher(rules, this);
  
          notifyHandler = new NotifyHandler(alarmRulesWatcher, getManager());
          notifyHandler.init(new AlarmStandardPersistence(getManager()));
          this.registerServiceImplementation(MetricsNotify.class, notifyHandler);
      }
  
      @Override
      public void start() throws ServiceNotProvidedException, ModuleStartException {
          DynamicConfigurationService dynamicConfigurationService = getManager().find(ConfigurationModule.NAME)
                                                                                .provider()
                                                                                .getService(
                                                                                    DynamicConfigurationService.class);
          dynamicConfigurationService.registerConfigChangeWatcher(alarmRulesWatcher);
      }
  
      @Override
      public void notifyAfterCompleted() throws ServiceNotProvidedException, ModuleStartException {
      }
  
      @Override
      public String[] requiredModules() {
          return new String[] {
              CoreModule.NAME,
              ConfigurationModule.NAME
          };
      }
  }
  