content: /*
   * 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 com.alibaba.jstorm.flux.parser;
  
  import com.alibaba.jstorm.flux.model.SpoutDef;
  import com.alibaba.jstorm.flux.model.BoltDef;
  import com.alibaba.jstorm.flux.model.IncludeDef;
  import com.alibaba.jstorm.flux.model.TopologyDef;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.yaml.snakeyaml.TypeDescription;
  import org.yaml.snakeyaml.Yaml;
  import org.yaml.snakeyaml.constructor.Constructor;
  
  import java.io.ByteArrayOutputStream;
  import java.io.FileInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.util.Map;
  import java.util.Properties;
  
  public class FluxParser {
      private static final Logger LOG = LoggerFactory.getLogger(FluxParser.class);
  
      private FluxParser(){}
  
      // TODO refactor input stream processing (see parseResource() method).
      public static TopologyDef parseFile(String inputFile, boolean dumpYaml, boolean processIncludes,
      	String propertiesFile, boolean envSub) throws IOException {
     
          FileInputStream in = new FileInputStream(inputFile);
          TopologyDef topology = parseInputStream(in, dumpYaml, processIncludes, propertiesFile, envSub);
          in.close();
          
          return topology;
      }
  
      public static TopologyDef parseResource(String resource, boolean dumpYaml, boolean processIncludes,
      	String propertiesFile, boolean envSub) throws IOException {
          
          InputStream in = FluxParser.class.getResourceAsStream(resource);
          TopologyDef topology = parseInputStream(in, dumpYaml, processIncludes, propertiesFile, envSub);
          in.close();
          
          return topology;
      }
      
      public static TopologyDef parseInputStream(InputStream inputStream, boolean dumpYaml, boolean processIncludes,
      	String propertiesFile, boolean envSub) throws IOException {
  		
  	Yaml yaml = yaml();
      	
  	if (inputStream == null) {
  		LOG.error("Unable to load input stream");
  		System.exit(1);
  	}
  		
  	TopologyDef topology = loadYaml(yaml, inputStream, propertiesFile, envSub);
  		
  	if (dumpYaml) {
  		dumpYaml(topology, yaml);
  	}
  	
  	if (processIncludes) {
  		return processIncludes(yaml, topology, propertiesFile, envSub);
  	} else {
  		return topology;
  	}
      }
  
      private static TopologyDef loadYaml(Yaml yaml, InputStream in, String propsFile, boolean envSubstitution) throws IOException {
          ByteArrayOutputStream bos = new ByteArrayOutputStream();
          LOG.info("loading YAML from input stream...");
          int b = -1;
          while((b = in.read()) != -1){
              bos.write(b);
          }
  
          // TODO substitution implementation is not exactly efficient or kind to memory...
          String str = bos.toString();
          // properties file substitution
          if(propsFile != null){
              LOG.info("Performing property substitution.");
              InputStream propsIn = new FileInputStream(propsFile);
              Properties props = new Properties();
              props.load(propsIn);
              for(Object key : props.keySet()){
                  str = str.replace("${" + key + "}", props.getProperty((String)key));
              }
          } else {
              LOG.info("Not performing property substitution.");
          }
  
          // environment variable substitution
          if(envSubstitution){
              LOG.info("Performing environment variable substitution...");
              Map<String, String> envs = System.getenv();
              for(String key : envs.keySet()){
                  str = str.replace("${ENV-" + key + "}", envs.get(key));
              }
          } else {
              LOG.info("Not performing environment variable substitution.");
          }
          return (TopologyDef)yaml.load(str);
      }
  
      private static void dumpYaml(TopologyDef topology, Yaml yaml){
          System.out.println("Configuration (interpreted): \n" + yaml.dump(topology));
      }
  
      private static Yaml yaml(){
          Constructor constructor = new Constructor(TopologyDef.class);
  
          TypeDescription topologyDescription = new TypeDescription(TopologyDef.class);
          topologyDescription.putListPropertyType("spouts", SpoutDef.class);
          topologyDescription.putListPropertyType("bolts", BoltDef.class);
          topologyDescription.putListPropertyType("includes", IncludeDef.class);
          constructor.addTypeDescription(topologyDescription);
  
          Yaml  yaml = new Yaml(constructor);
          return yaml;
      }
  
      /**
       *
       * @param yaml the yaml parser for parsing the include file(s)
       * @param topologyDef the topology definition containing (possibly zero) includes
       * @return The TopologyDef with includes resolved.
       */
      private static TopologyDef processIncludes(Yaml yaml, TopologyDef topologyDef, String propsFile, boolean envSub)
              throws IOException {
          //TODO support multiple levels of includes
          if(topologyDef.getIncludes() != null) {
              for (IncludeDef include : topologyDef.getIncludes()){
                  TopologyDef includeTopologyDef = null;
                  if (include.isResource()) {
                      LOG.info("Loading includes from resource: {}", include.getFile());
                      includeTopologyDef = parseResource(include.getFile(), true, false, propsFile, envSub);
                  } else {
                      LOG.info("Loading includes from file: {}", include.getFile());
                      includeTopologyDef = parseFile(include.getFile(), true, false, propsFile, envSub);
                  }
  
                  // if overrides are disabled, we won't replace anything that already exists
                  boolean override = include.isOverride();
                  // name
                  if(includeTopologyDef.getName() != null){
                      topologyDef.setName(includeTopologyDef.getName(), override);
                  }
  
                  // config
                  if(includeTopologyDef.getConfig() != null) {
                      //TODO move this logic to the model class
                      Map<String, Object> config = topologyDef.getConfig();
                      Map<String, Object> includeConfig = includeTopologyDef.getConfig();
                      if(override) {
                          config.putAll(includeTopologyDef.getConfig());
                      } else {
                          for(String key : includeConfig.keySet()){
                              if(config.containsKey(key)){
                                  LOG.warn("Ignoring attempt to set topology config property '{}' with override == false", key);
                              }
                              else {
                                  config.put(key, includeConfig.get(key));
                              }
                          }
                      }
                  }
  
                  //component overrides
                  if(includeTopologyDef.getComponents() != null){
                      topologyDef.addAllComponents(includeTopologyDef.getComponents(), override);
                  }
                  //bolt overrides
                  if(includeTopologyDef.getBolts() != null){
                      topologyDef.addAllBolts(includeTopologyDef.getBolts(), override);
                  }
                  //spout overrides
                  if(includeTopologyDef.getSpouts() != null) {
                      topologyDef.addAllSpouts(includeTopologyDef.getSpouts(), override);
                  }
                  //stream overrides
                  //TODO streams should be uniquely identifiable
                  if(includeTopologyDef.getStreams() != null) {
                      topologyDef.addAllStreams(includeTopologyDef.getStreams(), override);
                  }
              } // end include processing
          }
          return topologyDef;
      }
  }
  