/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2014 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed 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 io.undertow.server.handlers.proxy.mod_cluster;

import java.io.IOException;
import java.net.InetSocketAddress;
import java.net.URI;
import java.util.concurrent.TimeUnit;

import io.undertow.UndertowLogger;
import io.undertow.client.ClientCallback;
import io.undertow.client.ClientConnection;
import io.undertow.client.ClientExchange;
import io.undertow.client.ClientRequest;
import io.undertow.client.UndertowClient;
import io.undertow.server.HttpServerExchange;
import io.undertow.server.handlers.proxy.ProxyCallback;
import io.undertow.server.handlers.proxy.ProxyConnection;
import io.undertow.util.Headers;
import io.undertow.util.Methods;
import io.undertow.util.SameThreadExecutor;
import org.xnio.ChannelExceptionHandler;
import org.xnio.ChannelListener;
import org.xnio.ChannelListeners;
import org.xnio.IoFuture;
import org.xnio.IoUtils;
import org.xnio.OptionMap;
import io.undertow.connector.ByteBufferPool;
import io.undertow.util.WorkerUtils;
import org.xnio.StreamConnection;
import org.xnio.XnioExecutor;
import org.xnio.XnioIoThread;
import org.xnio.XnioWorker;
import org.xnio.channels.StreamSinkChannel;
import org.xnio.channels.StreamSourceChannel;
import org.xnio.ssl.XnioSsl;

Utilities to ping a remote node.
Author:Emanuel Muckenhuber
/** * Utilities to ping a remote node. * * @author Emanuel Muckenhuber */
class NodePingUtil { interface PingCallback {
Ping completed.
/** * Ping completed. */
void completed();
Ping failed.
/** * Ping failed. */
void failed(); }
Try to open a socket connection to given address.
Params:
  • address – the socket address
  • exchange – the http servers exchange
  • callback – the ping callback
  • options – the options
/** * Try to open a socket connection to given address. * * @param address the socket address * @param exchange the http servers exchange * @param callback the ping callback * @param options the options */
static void pingHost(InetSocketAddress address, HttpServerExchange exchange, PingCallback callback, OptionMap options) { final XnioIoThread thread = exchange.getIoThread(); final XnioWorker worker = thread.getWorker(); final HostPingTask r = new HostPingTask(address, worker, callback, options); // Schedule timeout task scheduleCancelTask(exchange.getIoThread(), r, 5, TimeUnit.SECONDS); exchange.dispatch(exchange.isInIoThread() ? SameThreadExecutor.INSTANCE : thread, r); }
Try to ping a server using the undertow client.
Params:
  • connection – the connection URI
  • callback – the ping callback
  • exchange – the http servers exchange
  • client – the undertow client
  • xnioSsl – the ssl setup
  • options – the options
/** * Try to ping a server using the undertow client. * * @param connection the connection URI * @param callback the ping callback * @param exchange the http servers exchange * @param client the undertow client * @param xnioSsl the ssl setup * @param options the options */
static void pingHttpClient(URI connection, PingCallback callback, HttpServerExchange exchange, UndertowClient client, XnioSsl xnioSsl, OptionMap options) { final XnioIoThread thread = exchange.getIoThread(); final RequestExchangeListener exchangeListener = new RequestExchangeListener(callback, NodeHealthChecker.NO_CHECK, true); final Runnable r = new HttpClientPingTask(connection, exchangeListener, thread, client, xnioSsl, exchange.getConnection().getByteBufferPool(), options); exchange.dispatch(exchange.isInIoThread() ? SameThreadExecutor.INSTANCE : thread, r); // Schedule timeout task scheduleCancelTask(exchange.getIoThread(), exchangeListener, 5, TimeUnit.SECONDS); }
Try to ping a node using it's connection pool.
Params:
  • node – the node
  • exchange – the http servers exchange
  • callback – the ping callback
/** * Try to ping a node using it's connection pool. * * @param node the node * @param exchange the http servers exchange * @param callback the ping callback */
static void pingNode(final Node node, final HttpServerExchange exchange, final PingCallback callback) { if (node == null) { callback.failed(); return; } final int timeout = node.getNodeConfig().getPing(); exchange.dispatch(exchange.isInIoThread() ? SameThreadExecutor.INSTANCE : exchange.getIoThread(), new Runnable() { @Override public void run() { node.getConnectionPool().connect(null, exchange, new ProxyCallback<ProxyConnection>() { @Override public void completed(final HttpServerExchange exchange, ProxyConnection result) { final RequestExchangeListener exchangeListener = new RequestExchangeListener(callback, NodeHealthChecker.NO_CHECK, false); exchange.dispatch(SameThreadExecutor.INSTANCE, new ConnectionPoolPingTask(result, exchangeListener, node.getNodeConfig().getConnectionURI())); // Schedule timeout task scheduleCancelTask(exchange.getIoThread(), exchangeListener, timeout, TimeUnit.SECONDS); } @Override public void failed(HttpServerExchange exchange) { callback.failed(); } @Override public void queuedRequestFailed(HttpServerExchange exchange) { callback.failed(); } @Override public void couldNotResolveBackend(HttpServerExchange exchange) { callback.failed(); } }, timeout, TimeUnit.SECONDS, false); } }); }
Internally ping a node. This should probably use the connections from the nodes pool, if there are any available.
Params:
  • node – the node
  • callback – the ping callback
  • ioThread – the xnio i/o thread
  • bufferPool – the xnio buffer pool
  • client – the undertow client
  • xnioSsl – the ssl setup
  • options – the options
/** * Internally ping a node. This should probably use the connections from the nodes pool, if there are any available. * * @param node the node * @param callback the ping callback * @param ioThread the xnio i/o thread * @param bufferPool the xnio buffer pool * @param client the undertow client * @param xnioSsl the ssl setup * @param options the options */
static void internalPingNode(Node node, PingCallback callback, NodeHealthChecker healthChecker, XnioIoThread ioThread, ByteBufferPool bufferPool, UndertowClient client, XnioSsl xnioSsl, OptionMap options) { final URI uri = node.getNodeConfig().getConnectionURI(); final long timeout = node.getNodeConfig().getPing(); final RequestExchangeListener exchangeListener = new RequestExchangeListener(callback, healthChecker, true); final HttpClientPingTask r = new HttpClientPingTask(uri, exchangeListener, ioThread, client, xnioSsl, bufferPool, options); // Schedule timeout task scheduleCancelTask(ioThread, exchangeListener, timeout, TimeUnit.SECONDS); ioThread.execute(r); } static class ConnectionPoolPingTask implements Runnable { private final RequestExchangeListener exchangeListener; private final ProxyConnection proxyConnection; private final URI uri; ConnectionPoolPingTask(ProxyConnection proxyConnection, RequestExchangeListener exchangeListener, URI uri) { this.proxyConnection = proxyConnection; this.exchangeListener = exchangeListener; this.uri = uri; } @Override public void run() { // TODO AJP has a special ping thing final ClientRequest request = new ClientRequest(); request.setMethod(Methods.OPTIONS); request.setPath("*"); request.getRequestHeaders() .add(Headers.USER_AGENT, "mod_cluster ping") .add(Headers.HOST, uri.getHost()); proxyConnection.getConnection().sendRequest(request, new ClientCallback<ClientExchange>() { @Override public void completed(final ClientExchange result) { if (exchangeListener.isDone()) { IoUtils.safeClose(proxyConnection.getConnection()); return; } exchangeListener.exchange = result; result.setResponseListener(exchangeListener); try { result.getRequestChannel().shutdownWrites(); if (!result.getRequestChannel().flush()) { result.getRequestChannel().getWriteSetter().set(ChannelListeners.flushingChannelListener(null, new ChannelExceptionHandler<StreamSinkChannel>() { @Override public void handleException(StreamSinkChannel channel, IOException exception) { IoUtils.safeClose(proxyConnection.getConnection()); exchangeListener.taskFailed(); } })); result.getRequestChannel().resumeWrites(); } } catch (IOException e) { IoUtils.safeClose(proxyConnection.getConnection()); exchangeListener.taskFailed(); } } @Override public void failed(IOException e) { exchangeListener.taskFailed(); } }); } } static class HostPingTask extends CancellableTask implements Runnable { private final InetSocketAddress address; private final XnioWorker worker; private final OptionMap options; HostPingTask(InetSocketAddress address, XnioWorker worker, PingCallback callback, OptionMap options) { super(callback); this.address = address; this.worker = worker; this.options = options; } @Override public void run() { try { final IoFuture<StreamConnection> future = worker.openStreamConnection(address, new ChannelListener<StreamConnection>() { @Override public void handleEvent(StreamConnection channel) { IoUtils.safeClose(channel); // Close the channel right away } }, options); future.addNotifier(new IoFuture.HandlingNotifier<StreamConnection, Void>() { @Override public void handleCancelled(Void attachment) { cancel(); } @Override public void handleFailed(IOException exception, Void attachment) { taskFailed(); } @Override public void handleDone(StreamConnection data, Void attachment) { taskCompleted(); } }, null); } catch (Exception e) { taskFailed(); } } } static class HttpClientPingTask implements Runnable { private final URI connection; private final XnioIoThread thread; private final UndertowClient client; private final XnioSsl xnioSsl; private final ByteBufferPool bufferPool; private final OptionMap options; private final RequestExchangeListener exchangeListener; HttpClientPingTask(URI connection, RequestExchangeListener exchangeListener, XnioIoThread thread, UndertowClient client, XnioSsl xnioSsl, ByteBufferPool bufferPool, OptionMap options) { this.connection = connection; this.thread = thread; this.client = client; this.xnioSsl = xnioSsl; this.bufferPool = bufferPool; this.options = options; this.exchangeListener = exchangeListener; } @Override public void run() { UndertowLogger.ROOT_LOGGER.httpClientPingTask(connection); // TODO AJP has a special ping thing client.connect(new ClientCallback<ClientConnection>() { @Override public void completed(final ClientConnection clientConnection) { if (exchangeListener.isDone()) { IoUtils.safeClose(clientConnection); return; } final ClientRequest request = new ClientRequest(); request.setMethod(Methods.OPTIONS); request.setPath("*"); request.getRequestHeaders() .add(Headers.USER_AGENT, "mod_cluster ping") .add(Headers.HOST, connection.getHost()); clientConnection.sendRequest(request, new ClientCallback<ClientExchange>() { @Override public void completed(ClientExchange result) { exchangeListener.exchange = result; if (exchangeListener.isDone()) { return; } result.setResponseListener(exchangeListener); try { result.getRequestChannel().shutdownWrites(); if (!result.getRequestChannel().flush()) { result.getRequestChannel().getWriteSetter().set(ChannelListeners.flushingChannelListener(null, new ChannelExceptionHandler<StreamSinkChannel>() { @Override public void handleException(StreamSinkChannel channel, IOException exception) { IoUtils.safeClose(clientConnection); exchangeListener.taskFailed(); } })); result.getRequestChannel().resumeWrites(); } } catch (IOException e) { IoUtils.safeClose(clientConnection); exchangeListener.taskFailed(); } } @Override public void failed(IOException e) { exchangeListener.taskFailed(); IoUtils.safeClose(clientConnection); } }); } @Override public void failed(IOException e) { exchangeListener.taskFailed(); } }, connection, thread, xnioSsl, bufferPool, options); } } static class RequestExchangeListener extends CancellableTask implements ClientCallback<ClientExchange> { private ClientExchange exchange; private final boolean closeConnection; private final NodeHealthChecker healthChecker; RequestExchangeListener(PingCallback callback, NodeHealthChecker healthChecker, boolean closeConnection) { super(callback); assert healthChecker != null; this.closeConnection = closeConnection; this.healthChecker = healthChecker; } @Override public void completed(final ClientExchange result) { if (isDone()) { IoUtils.safeClose(result.getConnection()); return; } final ChannelListener<StreamSourceChannel> listener = ChannelListeners.drainListener(Long.MAX_VALUE, new ChannelListener<StreamSourceChannel>() { @Override public void handleEvent(StreamSourceChannel channel) { try { if (healthChecker.checkResponse(result.getResponse())) { taskCompleted(); } else { taskFailed(); } } finally { if (closeConnection) { if (exchange != null) { IoUtils.safeClose(exchange.getConnection()); } } } } }, new ChannelExceptionHandler<StreamSourceChannel>() { @Override public void handleException(StreamSourceChannel channel, IOException exception) { taskFailed(); if (exception != null) { IoUtils.safeClose(exchange.getConnection()); } } }); StreamSourceChannel responseChannel = result.getResponseChannel(); responseChannel.getReadSetter().set(listener); responseChannel.resumeReads(); listener.handleEvent(responseChannel); } @Override public void failed(IOException e) { taskFailed(); if (exchange != null) { IoUtils.safeClose(exchange.getConnection()); } } } enum State { WAITING, DONE, CANCELLED; } static class CancellableTask { private final PingCallback delegate; private volatile State state = State.WAITING; private volatile XnioExecutor.Key cancelKey; CancellableTask(PingCallback callback) { this.delegate = callback; } boolean isDone() { return state != State.WAITING; } void setCancelKey(XnioExecutor.Key cancelKey) { if (state == State.WAITING) { this.cancelKey = cancelKey; } else { cancelKey.remove(); } } void taskCompleted() { if (state == State.WAITING) { state = State.DONE; if (cancelKey != null) { cancelKey.remove(); } delegate.completed(); } } void taskFailed() { if (state == State.WAITING) { state = State.DONE; if (cancelKey != null) { cancelKey.remove(); } delegate.failed(); } } void cancel() { if (state == State.WAITING) { state = State.CANCELLED; if (cancelKey != null) { cancelKey.remove(); } delegate.failed(); } } } static void scheduleCancelTask(final XnioIoThread ioThread, final CancellableTask cancellable, final long timeout, final TimeUnit timeUnit ) { final XnioExecutor.Key key = WorkerUtils.executeAfter(ioThread, new Runnable() { @Override public void run() { cancellable.cancel(); } }, timeout, timeUnit); cancellable.setCancelKey(key); } }