common/src/main/java/org/apache/cassandra/sidecar/common/JmxClient.java - cassandra-sidecar - Git at Google

 /*
  * 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.cassandra.sidecar.common;

 import java.io.Closeable;
 import java.io.IOException;
 import java.net.MalformedURLException;
 import java.rmi.server.RMIClientSocketFactory;
 import java.rmi.server.RMISocketFactory;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Objects;
 import java.util.concurrent.TimeUnit;
 import java.util.function.BooleanSupplier;
 import java.util.function.Supplier;
 import javax.management.JMX;
 import javax.management.MBeanServerConnection;
 import javax.management.MalformedObjectNameException;
 import javax.management.Notification;
 import javax.management.NotificationListener;
 import javax.management.ObjectName;
 import javax.management.remote.JMXConnectionNotification;
 import javax.management.remote.JMXConnector;
 import javax.management.remote.JMXConnectorFactory;
 import javax.management.remote.JMXServiceURL;
 import javax.rmi.ssl.SslRMIClientSocketFactory;

 import com.google.common.util.concurrent.Uninterruptibles;

 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 import org.apache.cassandra.sidecar.common.exceptions.JmxAuthenticationException;
 import org.jetbrains.annotations.VisibleForTesting;

 /**
  * A simple wrapper around a JMX connection that makes it easier to get proxy instances.
  */
 public class JmxClient implements NotificationListener, Closeable
 {
     public static final String JMX_PROTOCOL = "rmi";
     public static final String JMX_URL_PATH_FORMAT = "/jndi/rmi://%s:%d/jmxrmi";
     public static final String REGISTRY_CONTEXT_SOCKET_FACTORY = "com.sun.jndi.rmi.factory.socket";
     private static final Logger LOGGER = LoggerFactory.getLogger(JmxClient.class);
     private final JMXServiceURL jmxServiceURL;
     private MBeanServerConnection mBeanServerConnection;
     private boolean connected = false;
     private JMXConnector jmxConnector;
     private final Supplier<String> roleSupplier;
     private final Supplier<String> passwordSupplier;
     private final BooleanSupplier enableSslSupplier;
     private final int jmxConnectionMaxRetries;
     private final long jmxConnectionRetryDelayMillis;

     /**
      * Creates a new client with the provided {@code host} and {@code port}.
      *
      * @param host the host of the JMX service
      * @param port the port of the JMX service
      */
     public JmxClient(String host, int port)
     {
         this(host, port, null, null, false);
     }

     /**
      * Creates a new client with the provided parameters
      *
      * @param host      the host of the JMX service
      * @param port      the port of the JMX service
      * @param role      the JMX role used for authentication
      * @param password  the JMX role password used for authentication
      * @param enableSSl true if SSL is enabled for JMX, false otherwise
      */
     public JmxClient(String host, int port, String role, String password, boolean enableSSl)
     {
         this(buildJmxServiceURL(host, port), () -> role, () -> password, () -> enableSSl);
     }

     /**
      * Creates a new client with the provided parameters
      *
      * @param host                       the host of the JMX service
      * @param port                       the port of the JMX service
      * @param role                       the JMX role used for authentication
      * @param password                   the JMX role password used for authentication
      * @param enableSSl                  true if SSL is enabled for JMX, false otherwise
      * @param connectionMaxRetries       the maximum number of connection retries before failing to connect
      * @param connectionRetryDelayMillis the number of milliseconds to delay between connection retries
      */
     public JmxClient(String host, int port, String role, String password,
                      boolean enableSSl, int connectionMaxRetries, long connectionRetryDelayMillis)
     {
         this(buildJmxServiceURL(host, port), () -> role, () -> password, () -> enableSSl,
              connectionMaxRetries, connectionRetryDelayMillis);
     }

     @VisibleForTesting
     JmxClient(JMXServiceURL jmxServiceURL)
     {
         this(jmxServiceURL, () -> null, () -> null, () -> false);
     }

     @VisibleForTesting
     JmxClient(JMXServiceURL jmxServiceURL, String role, String password)
     {
         this(jmxServiceURL, () -> role, () -> password, () -> false);
     }

     public JmxClient(String host,
                      int port,
                      Supplier<String> roleSupplier,
                      Supplier<String> passwordSupplier,
                      BooleanSupplier enableSslSupplier)
     {
         this(buildJmxServiceURL(host, port), roleSupplier, passwordSupplier, enableSslSupplier);
     }

     public JmxClient(JMXServiceURL jmxServiceURL,
                      Supplier<String> roleSupplier,
                      Supplier<String> passwordSupplier,
                      BooleanSupplier enableSslSupplier)
     {
         this(jmxServiceURL, roleSupplier, passwordSupplier, enableSslSupplier, 20, 1000);
     }

     public JmxClient(JMXServiceURL jmxServiceURL,
                      Supplier<String> roleSupplier,
                      Supplier<String> passwordSupplier,
                      BooleanSupplier enableSslSupplier,
                      int jmxConnectionMaxRetries,
                      long jmxConnectionRetryDelayMillis)
     {
         this.jmxServiceURL = Objects.requireNonNull(jmxServiceURL, "jmxServiceURL is required");
         this.roleSupplier = Objects.requireNonNull(roleSupplier, "roleSupplier is required");
         this.passwordSupplier = Objects.requireNonNull(passwordSupplier, "passwordSupplier is required");
         this.enableSslSupplier = Objects.requireNonNull(enableSslSupplier, "enableSslSupplier is required");
         this.jmxConnectionMaxRetries = jmxConnectionMaxRetries;
         this.jmxConnectionRetryDelayMillis = jmxConnectionRetryDelayMillis;
     }

     /**
      * Returns a proxy for a Standard MBean in a local or remote MBean Server.
      *
      * @param clientClass the management interface that the MBean exports, which will
      *                    also be implemented by the returned proxy
      * @param remoteName  the name of the MBean within {@code connection} to forward to
      * @param <C>         the type of the proxy client
      * @return the proxy for a Standard MBean in a local or remote MBean Server
      */
     public <C> C proxy(Class<C> clientClass, String remoteName)
     {
         checkConnection();
         try
         {
             // NOTE: We get a new proxy each time we need one (much of the underlying construction is
             // cached by the JMX infrastructure, so we believe this to not be terribly resource-intensive
             ObjectName name = new ObjectName(remoteName);
             return JMX.newMBeanProxy(mBeanServerConnection, name, clientClass);
         }
         catch (MalformedObjectNameException e)
         {
             throw new RuntimeException(String.format("Invalid remote object name '%s'", remoteName), e);
         }
     }

     private RMIClientSocketFactory rmiClientSocketFactory(boolean enableSsl)
     {
         return enableSsl
                ? new SslRMIClientSocketFactory()
                : RMISocketFactory.getDefaultSocketFactory();
     }

     private synchronized void checkConnection()
     {
         if (!this.connected)
         {
             connect();
         }
     }

     private void connect()
     {
         int attempts = 1;
         int maxAttempts = jmxConnectionMaxRetries;
         Throwable lastThrown = null;
         while (attempts <= maxAttempts)
         {
             try
             {
                 connectInternal(attempts);
                 return;
             }
             // Unrecoverable errors
             catch (SecurityException securityException)
             {
                 // If we can't connect because we have bad credentials, don't retry
                 connected = false;
                 String errorMessage = securityException.getMessage() != null
                                       ? securityException.getMessage()
                                       : "JMX Authentication failed";
                 throw new JmxAuthenticationException(errorMessage, securityException);
             }
             catch (RuntimeException runtimeException)
             {
                 // catch exceptions coming from the lambdas and wrap them in a JmxAuthenticationException
                 throw new JmxAuthenticationException(runtimeException);
             }
             // Anything else is recoverable so we should retry.
             catch (Throwable t)
             {
                 lastThrown = t;
                 if (attempts < maxAttempts)
                 {
                     LOGGER.info("Could not connect to JMX on {} after {} attempts. Will retry.",
                                 jmxServiceURL, attempts, t);
                     Uninterruptibles.sleepUninterruptibly(jmxConnectionRetryDelayMillis, TimeUnit.MILLISECONDS);
                 }
                 attempts++;
             }
         }
         String error = "Failed to connect to JMX, which was unreachable after " + attempts + " attempts.";
         LOGGER.error(error, lastThrown);
         throw new RuntimeException(error, lastThrown);
     }

     private void connectInternal(int currentAttempt) throws IOException
     {
         jmxConnector = JMXConnectorFactory.connect(jmxServiceURL, buildJmxEnv());
         jmxConnector.addConnectionNotificationListener(this, null, null);
         mBeanServerConnection = jmxConnector.getMBeanServerConnection();
         connected = true;
         LOGGER.info("Connected to JMX server at {} after {} attempt(s)",
                     jmxServiceURL, currentAttempt);
     }

     @Override
     public void handleNotification(Notification notification, Object handback)
     {
         if (notification instanceof JMXConnectionNotification)
         {
             JMXConnectionNotification connectNotice = (JMXConnectionNotification) notification;
             final String type = connectNotice.getType();
             if (type.equals(JMXConnectionNotification.CLOSED) ||
                 type.equals(JMXConnectionNotification.FAILED) ||
                 type.equals(JMXConnectionNotification.NOTIFS_LOST) ||
                 type.equals(JMXConnectionNotification.OPENED))
             {
                 boolean justConnected = type.equals(JMXConnectionNotification.OPENED);
                 synchronized (this)
                 {
                     this.connected = justConnected;
                 }
             }
         }
     }

     /**
      * @return true if JMX is connected, false otherwise
      */
     public boolean isConnected()
     {
         return connected;
     }

     public String host()
     {
         return jmxServiceURL.getHost();
     }

     public int port()
     {
         return jmxServiceURL.getPort();
     }

     private static JMXServiceURL buildJmxServiceURL(String host, int port)
     {
         if (host == null)
             return null;

         try
         {
             return new JMXServiceURL(JMX_PROTOCOL, host, port, jmxUrlPath(host, port));
         }
         catch (MalformedURLException e)
         {
             String errorMessage = String.format("Unable to build JMXServiceURL for host=%s, port=%d",
                                                 host, port);
             throw new RuntimeException(errorMessage, e);
         }
     }

     private Map<String, Object> buildJmxEnv()
     {
         String role = roleSupplier.get();
         String password = passwordSupplier.get();
         boolean enableSsl = enableSslSupplier.getAsBoolean();

         Map<String, Object> jmxEnv = new HashMap<>();
         if (role != null && password != null)
         {
             String[] credentials = new String[]{ role, password };
             jmxEnv.put(JMXConnector.CREDENTIALS, credentials);
         }
         jmxEnv.put(REGISTRY_CONTEXT_SOCKET_FACTORY, rmiClientSocketFactory(enableSsl));
         return jmxEnv;
     }

     @Override
     public void close() throws IOException
     {
         JMXConnector connector;
         synchronized (this)
         {
             connector = jmxConnector;
             jmxConnector = null;
             connected = false;
         }
         if (connector != null)
         {
             connector.close();
         }
     }

     private static String jmxUrlPath(String host, int port)
     {
         return String.format(JMX_URL_PATH_FORMAT, maybeAddSquareBrackets(host), port);
     }

     private static String maybeAddSquareBrackets(String host)
     {
         if (host == null // host is null
             || host.isEmpty() // or host is empty
             || host.charAt(0) == '[' // host already starts with square brackets
             || !host.contains(":")) // or host doesn't contain ":" (not an IPv6 address)
             return host;

         // Use square brackets to surround IPv6 addresses to fix CASSANDRA-7669 and CASSANDRA-17581
         return "[" + host + "]";
     }
 }
	/*
	* 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.cassandra.sidecar.common;

	import java.io.Closeable;
	import java.io.IOException;
	import java.net.MalformedURLException;
	import java.rmi.server.RMIClientSocketFactory;
	import java.rmi.server.RMISocketFactory;
	import java.util.HashMap;
	import java.util.Map;
	import java.util.Objects;
	import java.util.concurrent.TimeUnit;
	import java.util.function.BooleanSupplier;
	import java.util.function.Supplier;
	import javax.management.JMX;
	import javax.management.MBeanServerConnection;
	import javax.management.MalformedObjectNameException;
	import javax.management.Notification;
	import javax.management.NotificationListener;
	import javax.management.ObjectName;
	import javax.management.remote.JMXConnectionNotification;
	import javax.management.remote.JMXConnector;
	import javax.management.remote.JMXConnectorFactory;
	import javax.management.remote.JMXServiceURL;
	import javax.rmi.ssl.SslRMIClientSocketFactory;

	import com.google.common.util.concurrent.Uninterruptibles;

	import org.slf4j.Logger;
	import org.slf4j.LoggerFactory;

	import org.apache.cassandra.sidecar.common.exceptions.JmxAuthenticationException;
	import org.jetbrains.annotations.VisibleForTesting;

	/**
	* A simple wrapper around a JMX connection that makes it easier to get proxy instances.
	*/
	public class JmxClient implements NotificationListener, Closeable
	{
	public static final String JMX_PROTOCOL = "rmi";
	public static final String JMX_URL_PATH_FORMAT = "/jndi/rmi://%s:%d/jmxrmi";
	public static final String REGISTRY_CONTEXT_SOCKET_FACTORY = "com.sun.jndi.rmi.factory.socket";
	private static final Logger LOGGER = LoggerFactory.getLogger(JmxClient.class);
	private final JMXServiceURL jmxServiceURL;
	private MBeanServerConnection mBeanServerConnection;
	private boolean connected = false;
	private JMXConnector jmxConnector;
	private final Supplier<String> roleSupplier;
	private final Supplier<String> passwordSupplier;
	private final BooleanSupplier enableSslSupplier;
	private final int jmxConnectionMaxRetries;
	private final long jmxConnectionRetryDelayMillis;

	/**
	* Creates a new client with the provided {@code host} and {@code port}.
	*
	* @param host the host of the JMX service
	* @param port the port of the JMX service
	*/
	public JmxClient(String host, int port)
	{
	this(host, port, null, null, false);
	}

	/**
	* Creates a new client with the provided parameters
	*
	* @param host the host of the JMX service
	* @param port the port of the JMX service
	* @param role the JMX role used for authentication
	* @param password the JMX role password used for authentication
	* @param enableSSl true if SSL is enabled for JMX, false otherwise
	*/
	public JmxClient(String host, int port, String role, String password, boolean enableSSl)
	{
	this(buildJmxServiceURL(host, port), () -> role, () -> password, () -> enableSSl);
	}

	/**
	* Creates a new client with the provided parameters
	*
	* @param host the host of the JMX service
	* @param port the port of the JMX service
	* @param role the JMX role used for authentication
	* @param password the JMX role password used for authentication
	* @param enableSSl true if SSL is enabled for JMX, false otherwise
	* @param connectionMaxRetries the maximum number of connection retries before failing to connect
	* @param connectionRetryDelayMillis the number of milliseconds to delay between connection retries
	*/
	public JmxClient(String host, int port, String role, String password,
	boolean enableSSl, int connectionMaxRetries, long connectionRetryDelayMillis)
	{
	this(buildJmxServiceURL(host, port), () -> role, () -> password, () -> enableSSl,
	connectionMaxRetries, connectionRetryDelayMillis);
	}

	@VisibleForTesting
	JmxClient(JMXServiceURL jmxServiceURL)
	{
	this(jmxServiceURL, () -> null, () -> null, () -> false);
	}

	@VisibleForTesting
	JmxClient(JMXServiceURL jmxServiceURL, String role, String password)
	{
	this(jmxServiceURL, () -> role, () -> password, () -> false);
	}

	public JmxClient(String host,
	int port,
	Supplier<String> roleSupplier,
	Supplier<String> passwordSupplier,
	BooleanSupplier enableSslSupplier)
	{
	this(buildJmxServiceURL(host, port), roleSupplier, passwordSupplier, enableSslSupplier);
	}

	public JmxClient(JMXServiceURL jmxServiceURL,
	Supplier<String> roleSupplier,
	Supplier<String> passwordSupplier,
	BooleanSupplier enableSslSupplier)
	{
	this(jmxServiceURL, roleSupplier, passwordSupplier, enableSslSupplier, 20, 1000);
	}

	public JmxClient(JMXServiceURL jmxServiceURL,
	Supplier<String> roleSupplier,
	Supplier<String> passwordSupplier,
	BooleanSupplier enableSslSupplier,
	int jmxConnectionMaxRetries,
	long jmxConnectionRetryDelayMillis)
	{
	this.jmxServiceURL = Objects.requireNonNull(jmxServiceURL, "jmxServiceURL is required");
	this.roleSupplier = Objects.requireNonNull(roleSupplier, "roleSupplier is required");
	this.passwordSupplier = Objects.requireNonNull(passwordSupplier, "passwordSupplier is required");
	this.enableSslSupplier = Objects.requireNonNull(enableSslSupplier, "enableSslSupplier is required");
	this.jmxConnectionMaxRetries = jmxConnectionMaxRetries;
	this.jmxConnectionRetryDelayMillis = jmxConnectionRetryDelayMillis;
	}

	/**
	* Returns a proxy for a Standard MBean in a local or remote MBean Server.
	*
	* @param clientClass the management interface that the MBean exports, which will
	* also be implemented by the returned proxy
	* @param remoteName the name of the MBean within {@code connection} to forward to
	* @param <C> the type of the proxy client
	* @return the proxy for a Standard MBean in a local or remote MBean Server
	*/
	public <C> C proxy(Class<C> clientClass, String remoteName)
	{
	checkConnection();
	try
	{
	// NOTE: We get a new proxy each time we need one (much of the underlying construction is
	// cached by the JMX infrastructure, so we believe this to not be terribly resource-intensive
	ObjectName name = new ObjectName(remoteName);
	return JMX.newMBeanProxy(mBeanServerConnection, name, clientClass);
	}
	catch (MalformedObjectNameException e)
	{
	throw new RuntimeException(String.format("Invalid remote object name '%s'", remoteName), e);
	}
	}

	private RMIClientSocketFactory rmiClientSocketFactory(boolean enableSsl)
	{
	return enableSsl
	? new SslRMIClientSocketFactory()
	: RMISocketFactory.getDefaultSocketFactory();
	}

	private synchronized void checkConnection()
	{
	if (!this.connected)
	{
	connect();
	}
	}

	private void connect()
	{
	int attempts = 1;
	int maxAttempts = jmxConnectionMaxRetries;
	Throwable lastThrown = null;
	while (attempts <= maxAttempts)
	{
	try
	{
	connectInternal(attempts);
	return;
	}
	// Unrecoverable errors
	catch (SecurityException securityException)
	{
	// If we can't connect because we have bad credentials, don't retry
	connected = false;
	String errorMessage = securityException.getMessage() != null
	? securityException.getMessage()
	: "JMX Authentication failed";
	throw new JmxAuthenticationException(errorMessage, securityException);
	}
	catch (RuntimeException runtimeException)
	{
	// catch exceptions coming from the lambdas and wrap them in a JmxAuthenticationException
	throw new JmxAuthenticationException(runtimeException);
	}
	// Anything else is recoverable so we should retry.
	catch (Throwable t)
	{
	lastThrown = t;
	if (attempts < maxAttempts)
	{
	LOGGER.info("Could not connect to JMX on {} after {} attempts. Will retry.",
	jmxServiceURL, attempts, t);
	Uninterruptibles.sleepUninterruptibly(jmxConnectionRetryDelayMillis, TimeUnit.MILLISECONDS);
	}
	attempts++;
	}
	}
	String error = "Failed to connect to JMX, which was unreachable after " + attempts + " attempts.";
	LOGGER.error(error, lastThrown);
	throw new RuntimeException(error, lastThrown);
	}

	private void connectInternal(int currentAttempt) throws IOException
	{
	jmxConnector = JMXConnectorFactory.connect(jmxServiceURL, buildJmxEnv());
	jmxConnector.addConnectionNotificationListener(this, null, null);
	mBeanServerConnection = jmxConnector.getMBeanServerConnection();
	connected = true;
	LOGGER.info("Connected to JMX server at {} after {} attempt(s)",
	jmxServiceURL, currentAttempt);
	}

	@Override
	public void handleNotification(Notification notification, Object handback)
	{
	if (notification instanceof JMXConnectionNotification)
	{
	JMXConnectionNotification connectNotice = (JMXConnectionNotification) notification;
	final String type = connectNotice.getType();
	if (type.equals(JMXConnectionNotification.CLOSED) \|\|
	type.equals(JMXConnectionNotification.FAILED) \|\|
	type.equals(JMXConnectionNotification.NOTIFS_LOST) \|\|
	type.equals(JMXConnectionNotification.OPENED))
	{
	boolean justConnected = type.equals(JMXConnectionNotification.OPENED);
	synchronized (this)
	{
	this.connected = justConnected;
	}
	}
	}
	}

	/**
	* @return true if JMX is connected, false otherwise
	*/
	public boolean isConnected()
	{
	return connected;
	}

	public String host()
	{
	return jmxServiceURL.getHost();
	}

	public int port()
	{
	return jmxServiceURL.getPort();
	}

	private static JMXServiceURL buildJmxServiceURL(String host, int port)
	{
	if (host == null)
	return null;

	try
	{
	return new JMXServiceURL(JMX_PROTOCOL, host, port, jmxUrlPath(host, port));
	}
	catch (MalformedURLException e)
	{
	String errorMessage = String.format("Unable to build JMXServiceURL for host=%s, port=%d",
	host, port);
	throw new RuntimeException(errorMessage, e);
	}
	}

	private Map<String, Object> buildJmxEnv()
	{
	String role = roleSupplier.get();
	String password = passwordSupplier.get();
	boolean enableSsl = enableSslSupplier.getAsBoolean();

	Map<String, Object> jmxEnv = new HashMap<>();
	if (role != null && password != null)
	{
	String[] credentials = new String[]{ role, password };
	jmxEnv.put(JMXConnector.CREDENTIALS, credentials);
	}
	jmxEnv.put(REGISTRY_CONTEXT_SOCKET_FACTORY, rmiClientSocketFactory(enableSsl));
	return jmxEnv;
	}

	@Override
	public void close() throws IOException
	{
	JMXConnector connector;
	synchronized (this)
	{
	connector = jmxConnector;
	jmxConnector = null;
	connected = false;
	}
	if (connector != null)
	{
	connector.close();
	}
	}

	private static String jmxUrlPath(String host, int port)
	{
	return String.format(JMX_URL_PATH_FORMAT, maybeAddSquareBrackets(host), port);
	}

	private static String maybeAddSquareBrackets(String host)
	{
	if (host == null // host is null
	\|\| host.isEmpty() // or host is empty
	\|\| host.charAt(0) == '[' // host already starts with square brackets
	\|\| !host.contains(":")) // or host doesn't contain ":" (not an IPv6 address)
	return host;

	// Use square brackets to surround IPv6 addresses to fix CASSANDRA-7669 and CASSANDRA-17581
	return "[" + host + "]";
	}
	}