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.camel.quarkus.test;
  
  import java.io.IOException;
  import java.net.DatagramSocket;
  import java.net.ServerSocket;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.Optional;
  import java.util.concurrent.ConcurrentHashMap;
  import java.util.function.Function;
  
  import org.eclipse.microprofile.config.Config;
  import org.eclipse.microprofile.config.ConfigProvider;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Finds currently available server ports.
   */
  public final class AvailablePortFinder {
      private static final Logger LOGGER = LoggerFactory.getLogger(AvailablePortFinder.class);
      private static final Map<Integer, String> RESERVED_PORTS = new ConcurrentHashMap<>();
      private static final String[] QUARKUS_PORT_PROPERTIES = new String[] {
              "quarkus.http.test-port",
              "quarkus.http.test-ssl-port",
              "quarkus.https.test-port",
      };
  
      /**
       * Creates a new instance.
       */
      private AvailablePortFinder() {
          // Do nothing
      }
  
      /**
       * Gets the next available TCP port.
       *
       * @throws IllegalStateException if there are no ports available
       * @return                       the available port
       */
      public static int getNextAvailable() {
          return getNextAvailable(Protocol.TCP);
      }
  
      /**
       * Gets the next available port for the given protocol.
       *
       * @param  protocol              the network protocol to reserve the port for. Either TCP or UDP
       * @throws IllegalStateException if there are no ports available
       * @return                       the available port
       */
      public static int getNextAvailable(Protocol protocol) {
          // Using AvailablePortFinder in native applications can be problematic
          // E.g The reserved port may be allocated at build time and preserved indefinitely at runtime. I.e it never changes on each execution of the native application
          logWarningIfNativeApplication();
  
          while (true) {
              try {
                  int port = protocol.getPort();
                  if (!isQuarkusReservedPort(port)) {
                      String callerClassName = getCallerClassName();
                      String value = RESERVED_PORTS.putIfAbsent(port, callerClassName);
                      if (value == null) {
                          LOGGER.info("{} reserved port {}", callerClassName, port);
                          return port;
                      }
                  }
              } catch (IOException e) {
                  throw new IllegalStateException("Cannot find free port", e);
              }
          }
      }
  
      /**
       * Reserve a list of random and not in use TCP network ports and places them in Map.
       */
      public static Map<String, Integer> reserveNetworkPorts(String... names) {
          return reserveNetworkPorts(Function.identity(), names);
      }
  
      /**
       * Reserve a list of random and not in use network ports for the given protocol and places them in Map.
       */
      public static Map<String, Integer> reserveNetworkPorts(Protocol protocol, String... names) {
          return reserveNetworkPorts(protocol, Function.identity(), names);
      }
  
      /**
       * Reserve a list of random and not in use TCP network ports and places them in Map.
       */
      public static <T> Map<String, T> reserveNetworkPorts(Function<Integer, T> converter, String... names) {
          return reserveNetworkPorts(Protocol.TCP, converter, names);
      }
  
      /**
       * Reserve a list of random and not in use network ports for the given protocol and places them in Map.
       */
      public static <T> Map<String, T> reserveNetworkPorts(Protocol protocol, Function<Integer, T> converter, String... names) {
          Map<String, T> reservedPorts = new HashMap<>();
  
          for (String name : names) {
              reservedPorts.put(name, converter.apply(getNextAvailable(protocol)));
          }
  
          return reservedPorts;
      }
  
      public static void releaseReservedPorts() {
          String callerClassName = getCallerClassName();
          RESERVED_PORTS.entrySet()
                  .stream()
                  .filter(entry -> entry.getValue().equals(callerClassName))
                  .peek(entry -> LOGGER.info("Releasing port {} reserved by {}", entry.getKey(), entry.getValue()))
                  .map(Map.Entry::getKey)
                  .forEach(RESERVED_PORTS::remove);
      }
  
      private static boolean isQuarkusReservedPort(int port) {
          Config config = ConfigProvider.getConfig();
          for (String property : QUARKUS_PORT_PROPERTIES) {
              Optional<Integer> portProperty = config.getOptionalValue(property, Integer.class);
              if (portProperty.isPresent()) {
                  if (port == portProperty.get()) {
                      LOGGER.info("Port {} is already reserved for {}", port, property);
                      return true;
                  }
              }
          }
          return false;
      }
  
      private static String getCallerClassName() {
          return StackWalker.getInstance(StackWalker.Option.RETAIN_CLASS_REFERENCE)
                  .walk(s -> s.map(StackWalker.StackFrame::getClassName)
                          .filter(className -> !className.equals(AvailablePortFinder.class.getName()))
                          .findFirst()
                          .orElseThrow(IllegalStateException::new));
      }
  
      private static void logWarningIfNativeApplication() {
          if (System.getProperty("org.graalvm.nativeimage.kind") != null) {
              LOGGER.warn("Usage of AvailablePortFinder in the native application is discouraged. "
                      + "Pass the reserved port to the native application under test with QuarkusTestResourceLifecycleManager or via an HTTP request");
          }
      }
  
      public enum Protocol {
          TCP,
          UDP;
  
          int getPort() throws IOException {
              if (this.equals(TCP)) {
                  try (ServerSocket socket = new ServerSocket()) {
                      socket.setReuseAddress(true);
                      socket.bind(null);
                      return socket.getLocalPort();
                  }
              }
  
              try (DatagramSocket socket = new DatagramSocket()) {
                  // NOTE: There's no need for socket.bind as it happens during DatagramSocket instantiation
                  socket.setReuseAddress(true);
                  return socket.getLocalPort();
              }
          }
      }
  }
  