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 org.apache.kafka.streams.processor.internals;
  
  import org.apache.kafka.streams.processor.StateStore;
  
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.util.ArrayList;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.List;
  import java.util.Map;
  import java.util.Optional;
  import java.util.Set;
  
  public class ProcessorTopology {
      private static final Logger log = LoggerFactory.getLogger(ProcessorTopology.class);
  
      private final List<ProcessorNode<?, ?, ?, ?>> processorNodes;
      private final Map<String, SourceNode<?, ?>> sourceNodesByName;
      private final Map<String, SourceNode<?, ?>> sourceNodesByTopic;
      private final Map<String, SinkNode<?, ?>> sinksByTopic;
      private final Set<String> terminalNodes;
      private final List<StateStore> stateStores;
      private final Set<String> repartitionTopics;
  
      // the following contains entries for the entire topology, eg stores that do not belong to this ProcessorTopology
      private final List<StateStore> globalStateStores;
      private final Map<String, String> storeToChangelogTopic;
      private final Map<String, Optional<InternalTopologyBuilder.ReprocessFactory<?, ?, ?, ?>>> storeNameToReprocessOnRestore;
  
      public ProcessorTopology(final List<ProcessorNode<?, ?, ?, ?>> processorNodes,
                               final Map<String, SourceNode<?, ?>> sourceNodesByTopic,
                               final Map<String, SinkNode<?, ?>> sinksByTopic,
                               final List<StateStore> stateStores,
                               final List<StateStore> globalStateStores,
                               final Map<String, String> storeToChangelogTopic,
                               final Set<String> repartitionTopics,
                               final Map<String, Optional<InternalTopologyBuilder.ReprocessFactory<?, ?, ?, ?>>> storeNameToReprocessOnRestore) {
          this.processorNodes = Collections.unmodifiableList(processorNodes);
          this.sourceNodesByTopic = new HashMap<>(sourceNodesByTopic);
          this.sinksByTopic = Collections.unmodifiableMap(sinksByTopic);
          this.stateStores = Collections.unmodifiableList(stateStores);
          this.globalStateStores = Collections.unmodifiableList(globalStateStores);
          this.storeToChangelogTopic = Collections.unmodifiableMap(storeToChangelogTopic);
          this.repartitionTopics = Collections.unmodifiableSet(repartitionTopics);
          this.storeNameToReprocessOnRestore = storeNameToReprocessOnRestore;
  
          this.terminalNodes = new HashSet<>();
          for (final ProcessorNode<?, ?, ?, ?> node : processorNodes) {
              if (node.isTerminalNode()) {
                  terminalNodes.add(node.name());
              }
          }
  
          this.sourceNodesByName = new HashMap<>();
          for (final SourceNode<?, ?> source : sourceNodesByTopic.values()) {
              sourceNodesByName.put(source.name(), source);
          }
      }
  
      public Set<String> sourceTopics() {
          return sourceNodesByTopic.keySet();
      }
  
      public SourceNode<?, ?> source(final String topic) {
          return sourceNodesByTopic.get(topic);
      }
  
      public Set<SourceNode<?, ?>> sources() {
          return new HashSet<>(sourceNodesByTopic.values());
      }
  
      public Set<String> sinkTopics() {
          return sinksByTopic.keySet();
      }
  
      public SinkNode<?, ?> sink(final String topic) {
          return sinksByTopic.get(topic);
      }
  
      public Set<String> terminalNodes() {
          return terminalNodes;
      }
  
      public List<ProcessorNode<?, ?, ?, ?>> processors() {
          return processorNodes;
      }
  
      public List<StateStore> stateStores() {
          return stateStores;
      }
  
      public Map<String, Optional<InternalTopologyBuilder.ReprocessFactory<?, ?, ?, ?>>> storeNameToReprocessOnRestore() {
          return storeNameToReprocessOnRestore;
      }
  
      public List<StateStore> globalStateStores() {
          return Collections.unmodifiableList(globalStateStores);
      }
  
      public Map<String, String> storeToChangelogTopic() {
          return Collections.unmodifiableMap(storeToChangelogTopic);
      }
  
      boolean isRepartitionTopic(final String topic) {
          return repartitionTopics.contains(topic);
      }
  
      boolean hasStateWithChangelogs() {
          for (final StateStore stateStore : stateStores) {
              if (storeToChangelogTopic.containsKey(stateStore.name())) {
                  return true;
              }
          }
          return false;
      }
  
      public boolean hasPersistentLocalStore() {
          for (final StateStore store : stateStores) {
              if (store.persistent()) {
                  return true;
              }
          }
          return false;
      }
  
      public boolean hasPersistentGlobalStore() {
          for (final StateStore store : globalStateStores) {
              if (store.persistent()) {
                  return true;
              }
          }
          return false;
      }
  
      public void updateSourceTopics(final Map<String, List<String>> allSourceTopicsByNodeName) {
          sourceNodesByTopic.clear();
          for (final Map.Entry<String, SourceNode<?, ?>> sourceNodeEntry : sourceNodesByName.entrySet()) {
              final String sourceNodeName = sourceNodeEntry.getKey();
              final SourceNode<?, ?> sourceNode = sourceNodeEntry.getValue();
  
              final List<String> updatedSourceTopics = allSourceTopicsByNodeName.get(sourceNodeName);
              if (updatedSourceTopics == null) {
                  log.error("Unable to find source node {} in updated topics map {}",
                            sourceNodeName, allSourceTopicsByNodeName);
                  throw new IllegalStateException("Node " + sourceNodeName + " not found in full topology");
              }
  
              log.trace("Updating source node {} with new topics {}", sourceNodeName, updatedSourceTopics);
              for (final String topic : updatedSourceTopics) {
                  if (sourceNodesByTopic.containsKey(topic)) {
                      log.error("Tried to subscribe topic {} to two nodes when updating topics from {}",
                                topic, allSourceTopicsByNodeName);
                      throw new IllegalStateException("Topic " + topic + " was already registered to source node "
                                                          + sourceNodesByTopic.get(topic).name());
                  }
                  sourceNodesByTopic.put(topic, sourceNode);
              }
          }
      }
  
      private String childrenToString(final String indent, final List<? extends ProcessorNode<?, ?, ?, ?>> children) {
          if (children == null || children.isEmpty()) {
              return "";
          }
  
          final StringBuilder sb = new StringBuilder(indent + "\tchildren:\t[");
          for (final ProcessorNode<?, ?, ?, ?> child : children) {
              sb.append(child.name());
              sb.append(", ");
          }
          sb.setLength(sb.length() - 2);  // remove the last comma
          sb.append("]\n");
  
          // recursively print children
          for (final ProcessorNode<?, ?, ?, ?> child : children) {
              sb.append(child.toString(indent)).append(childrenToString(indent, child.children()));
          }
          return sb.toString();
      }
  
      /**
       * Produces a string representation containing useful information this topology starting with the given indent.
       * This is useful in debugging scenarios.
       * @return A string representation of this instance.
       */
      @Override
      public String toString() {
          return toString("");
      }
  
      /**
       * Produces a string representation containing useful information this topology.
       * This is useful in debugging scenarios.
       * @return A string representation of this instance.
       */
      public String toString(final String indent) {
          final Map<SourceNode<?, ?>, List<String>> sourceToTopics = new HashMap<>();
          for (final Map.Entry<String, SourceNode<?, ?>> sourceNodeEntry : sourceNodesByTopic.entrySet()) {
              final String topic = sourceNodeEntry.getKey();
              final SourceNode<?, ?> source = sourceNodeEntry.getValue();
              sourceToTopics.computeIfAbsent(source, s -> new ArrayList<>());
              sourceToTopics.get(source).add(topic);
          }
  
          final StringBuilder sb = new StringBuilder(indent + "ProcessorTopology:\n");
  
          // start from sources
          for (final Map.Entry<SourceNode<?, ?>, List<String>> sourceNodeEntry : sourceToTopics.entrySet()) {
              final SourceNode<?, ?> source = sourceNodeEntry.getKey();
              final List<String> topics = sourceNodeEntry.getValue();
              sb.append(source.toString(indent + "\t"))
                  .append(topicsToString(indent + "\t", topics))
                  .append(childrenToString(indent + "\t", source.children()));
          }
          return sb.toString();
      }
  
      private static String topicsToString(final String indent, final List<String> topics) {
          final StringBuilder sb = new StringBuilder();
          sb.append(indent).append("\ttopics:\t\t[");
          for (final String topic : topics) {
              sb.append(topic);
              sb.append(", ");
          }
          sb.setLength(sb.length() - 2);  // remove the last comma
          sb.append("]\n");
          return sb.toString();
      }
  
      // for testing only
      public Set<String> processorConnectedStateStores(final String processorName) {
          for (final ProcessorNode<?, ?, ?, ?> node : processorNodes) {
              if (node.name().equals(processorName)) {
                  return node.stateStores;
              }
          }
  
          return Collections.emptySet();
      }
  }
  