/*
* JBoss, Home of Professional Open Source.
* Copyright 2012 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.servlet.spec;
import java.io.IOException;
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;
import javax.servlet.AsyncContext;
import javax.servlet.AsyncEvent;
import javax.servlet.AsyncListener;
import javax.servlet.DispatcherType;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import io.undertow.UndertowLogger;
import io.undertow.server.Connectors;
import io.undertow.server.HttpHandler;
import io.undertow.server.HttpServerExchange;
import io.undertow.servlet.UndertowServletLogger;
import io.undertow.servlet.UndertowServletMessages;
import io.undertow.servlet.api.Deployment;
import io.undertow.servlet.api.DeploymentManager;
import io.undertow.servlet.api.InstanceFactory;
import io.undertow.servlet.api.ServletContainer;
import io.undertow.servlet.api.ServletDispatcher;
import io.undertow.servlet.api.ThreadSetupAction;
import io.undertow.servlet.core.CompositeThreadSetupAction;
import io.undertow.servlet.handlers.ServletDebugPageHandler;
import io.undertow.servlet.handlers.ServletPathMatch;
import io.undertow.servlet.handlers.ServletRequestContext;
import io.undertow.util.AttachmentKey;
import io.undertow.util.CanonicalPathUtils;
import io.undertow.util.SameThreadExecutor;
import org.xnio.IoUtils;
import org.xnio.XnioExecutor;
/**
* @author Stuart Douglas
*/
public class AsyncContextImpl implements AsyncContext {
public static final AttachmentKey<Boolean> ASYNC_SUPPORTED = AttachmentKey.create(Boolean.class);
public static final AttachmentKey<Executor> ASYNC_EXECUTOR = AttachmentKey.create(Executor.class);
private final List<BoundAsyncListener> asyncListeners = new CopyOnWriteArrayList<BoundAsyncListener>();
private final HttpServerExchange exchange;
private final ServletRequest servletRequest;
private final ServletResponse servletResponse;
private final TimeoutTask timeoutTask = new TimeoutTask();
private final ServletRequestContext servletRequestContext;
private final boolean requestSupplied;
private AsyncContextImpl previousAsyncContext; //the previous async context
//todo: make default configurable
private volatile long timeout = 30000;
private volatile XnioExecutor.Key timeoutKey;
private boolean dispatched;
private boolean initialRequestDone;
private Thread initiatingThread;
private final Deque<Runnable> asyncTaskQueue = new ArrayDeque<Runnable>();
private boolean processingAsyncTask = false;
private boolean complete = false;
public AsyncContextImpl(final HttpServerExchange exchange, final ServletRequest servletRequest, final ServletResponse servletResponse, final ServletRequestContext servletRequestContext, boolean requestSupplied, final AsyncContextImpl previousAsyncContext) {
this.exchange = exchange;
this.servletRequest = servletRequest;
this.servletResponse = servletResponse;
this.servletRequestContext = servletRequestContext;
this.requestSupplied = requestSupplied;
this.previousAsyncContext = previousAsyncContext;
initiatingThread = Thread.currentThread();
exchange.dispatch(SameThreadExecutor.INSTANCE, new Runnable() {
@Override
public void run() {
exchange.setDispatchExecutor(null);
initialRequestDone();
}
});
}
public void updateTimeout() {
XnioExecutor.Key key = this.timeoutKey;
if (key != null) {
if (!key.remove()) {
return;
}
}
if (timeout > 0) {
this.timeoutKey = exchange.getIoThread().executeAfter(timeoutTask, timeout, TimeUnit.MILLISECONDS);
}
}
@Override
public ServletRequest getRequest() {
return servletRequest;
}
@Override
public ServletResponse getResponse() {
return servletResponse;
}
@Override
public boolean hasOriginalRequestAndResponse() {
return servletRequest instanceof HttpServletRequestImpl &&
servletResponse instanceof HttpServletResponseImpl;
}
@Override
public void dispatch() {
if (dispatched) {
throw UndertowServletMessages.MESSAGES.asyncRequestAlreadyDispatched();
}
final HttpServletRequestImpl requestImpl = this.servletRequestContext.getOriginalRequest();
Deployment deployment = requestImpl.getServletContext().getDeployment();
if (requestSupplied && servletRequest instanceof HttpServletRequest) {
ServletContainer container = deployment.getServletContainer();
final String requestURI = ((HttpServletRequest) servletRequest).getRequestURI();
DeploymentManager context = container.getDeploymentByPath(requestURI);
if (context == null) {
throw UndertowServletMessages.MESSAGES.couldNotFindContextToDispatchTo(requestImpl.getOriginalContextPath());
}
String toDispatch = requestURI.substring(context.getDeployment().getServletContext().getContextPath().length());
String qs = ((HttpServletRequest) servletRequest).getQueryString();
if (qs != null && !qs.isEmpty()) {
toDispatch = toDispatch + "?" + qs;
}
dispatch(context.getDeployment().getServletContext(), toDispatch);
} else {
//original request
ServletContainer container = deployment.getServletContainer();
DeploymentManager context = container.getDeploymentByPath(requestImpl.getOriginalContextPath());
if (context == null) {
//this should never happen
throw UndertowServletMessages.MESSAGES.couldNotFindContextToDispatchTo(requestImpl.getOriginalContextPath());
}
String toDispatch = CanonicalPathUtils.canonicalize(requestImpl.getOriginalRequestURI()).substring(requestImpl.getOriginalContextPath().length());
String qs = requestImpl.getOriginalQueryString();
if (qs != null && !qs.isEmpty()) {
toDispatch = toDispatch + "?" + qs;
}
dispatch(context.getDeployment().getServletContext(), toDispatch);
}
}
private void dispatchAsyncRequest(final ServletDispatcher servletDispatcher, final ServletPathMatch pathInfo, final HttpServerExchange exchange) {
doDispatch(new Runnable() {
@Override
public void run() {
Connectors.executeRootHandler(new HttpHandler() {
@Override
public void handleRequest(final HttpServerExchange exchange) throws Exception {
servletDispatcher.dispatchToPath(exchange, pathInfo, DispatcherType.ASYNC);
}
}, exchange);
}
});
}
@Override
public void dispatch(final String path) {
dispatch(servletRequest.getServletContext(), path);
}
@Override
public void dispatch(final ServletContext context, final String path) {
if (dispatched) {
throw UndertowServletMessages.MESSAGES.asyncRequestAlreadyDispatched();
}
HttpServletRequestImpl requestImpl = servletRequestContext.getOriginalRequest();
HttpServletResponseImpl responseImpl = servletRequestContext.getOriginalResponse();
final HttpServerExchange exchange = requestImpl.getExchange();
exchange.getAttachment(ServletRequestContext.ATTACHMENT_KEY).setDispatcherType(DispatcherType.ASYNC);
requestImpl.setAttribute(ASYNC_REQUEST_URI, requestImpl.getOriginalRequestURI());
requestImpl.setAttribute(ASYNC_CONTEXT_PATH, requestImpl.getOriginalContextPath());
requestImpl.setAttribute(ASYNC_SERVLET_PATH, requestImpl.getOriginalServletPath());
requestImpl.setAttribute(ASYNC_QUERY_STRING, requestImpl.getOriginalQueryString());
String newQueryString = "";
int qsPos = path.indexOf("?");
String newServletPath = path;
if (qsPos != -1) {
newQueryString = newServletPath.substring(qsPos + 1);
newServletPath = newServletPath.substring(0, qsPos);
}
String newRequestUri = context.getContextPath() + newServletPath;
//todo: a more efficient impl
Map<String, Deque<String>> newQueryParameters = new HashMap<String, Deque<String>>();
for (String part : newQueryString.split("&")) {
String name = part;
String value = "";
int equals = part.indexOf('=');
if (equals != -1) {
name = part.substring(0, equals);
value = part.substring(equals + 1);
}
Deque<String> queue = newQueryParameters.get(name);
if (queue == null) {
newQueryParameters.put(name, queue = new ArrayDeque<String>(1));
}
queue.add(value);
}
requestImpl.setQueryParameters(newQueryParameters);
requestImpl.getExchange().setRelativePath(newServletPath);
requestImpl.getExchange().setQueryString(newQueryString);
requestImpl.getExchange().setRequestPath(newRequestUri);
requestImpl.getExchange().setRequestURI(newRequestUri);
requestImpl.setServletContext((ServletContextImpl) context);
responseImpl.setServletContext((ServletContextImpl) context);
Deployment deployment = requestImpl.getServletContext().getDeployment();
ServletPathMatch info = deployment.getServletPaths().getServletHandlerByPath(newServletPath);
requestImpl.getExchange().getAttachment(ServletRequestContext.ATTACHMENT_KEY).setServletPathMatch(info);
dispatchAsyncRequest(deployment.getServletDispatcher(), info, exchange);
}
@Override
public synchronized void complete() {
if(complete) {
UndertowLogger.REQUEST_LOGGER.trace("Ignoring call to AsyncContext.complete() as it has already been called");
return;
}
complete = true;
onAsyncComplete();
if(!dispatched) {
completeInternal();
}
if(previousAsyncContext != null) {
previousAsyncContext.complete();
}
}
public synchronized void completeInternal() {
if (!initialRequestDone && Thread.currentThread() == initiatingThread) {
//the context was stopped in the same request context it was started, we don't do anything
if (dispatched) {
throw UndertowServletMessages.MESSAGES.asyncRequestAlreadyDispatched();
}
exchange.unDispatch();
dispatched = true;
initialRequestDone();
} else {
doDispatch(new Runnable() {
@Override
public void run() {
//we do not run the ServletRequestListeners here, as the request does not come into the scope
//of a web application, as defined by the javadoc on ServletRequestListener
HttpServletResponseImpl response = servletRequestContext.getOriginalResponse();
response.responseDone();
}
});
}
}
@Override
public void start(final Runnable run) {
Executor executor = asyncExecutor();
final CompositeThreadSetupAction setup = servletRequestContext.getDeployment().getThreadSetupAction();
executor.execute(new Runnable() {
@Override
public void run() {
ThreadSetupAction.Handle handle = setup.setup(null);
try {
run.run();
} finally {
handle.tearDown();
}
}
});
}
private Executor asyncExecutor() {
Executor executor = exchange.getAttachment(ASYNC_EXECUTOR);
if (executor == null) {
executor = exchange.getDispatchExecutor();
}
if (executor == null) {
executor = exchange.getConnection().getWorker();
}
return executor;
}
@Override
public void addListener(final AsyncListener listener) {
asyncListeners.add(new BoundAsyncListener(listener, servletRequest, servletResponse));
}
@Override
public void addListener(final AsyncListener listener, final ServletRequest servletRequest, final ServletResponse servletResponse) {
asyncListeners.add(new BoundAsyncListener(listener, servletRequest, servletResponse));
}
public boolean isDispatched() {
return dispatched;
}
@Override
public <T extends AsyncListener> T createListener(final Class<T> clazz) throws ServletException {
try {
InstanceFactory<T> factory = ((ServletContextImpl) this.servletRequest.getServletContext()).getDeployment().getDeploymentInfo().getClassIntrospecter().createInstanceFactory(clazz);
return factory.createInstance().getInstance();
} catch (Exception e) {
throw new ServletException(e);
}
}
@Override
public void setTimeout(final long timeout) {
if (initialRequestDone) {
throw UndertowServletMessages.MESSAGES.asyncRequestAlreadyReturnedToContainer();
}
this.timeout = timeout;
}
@Override
public long getTimeout() {
return timeout;
}
public void handleError(final Throwable error) {
dispatched = false; //we reset the dispatched state
onAsyncError(error);
if (!dispatched) {
servletRequest.setAttribute(RequestDispatcher.ERROR_EXCEPTION, error);
try {
boolean errorPage = servletRequestContext.displayStackTraces();
if(errorPage) {
ServletDebugPageHandler.handleRequest(exchange, servletRequestContext, error);
} else {
if (servletResponse instanceof HttpServletResponse) {
((HttpServletResponse) servletResponse).sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
} else {
servletRequestContext.getOriginalResponse().sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}
}
} catch (IOException e) {
UndertowLogger.REQUEST_IO_LOGGER.ioException(e);
}
if (!dispatched) {
complete();
}
}
}
/**
* Called by the container when the initial request is finished.
* If this request has a dispatch or complete call pending then
* this will be started.
*/
public synchronized void initialRequestDone() {
initialRequestDone = true;
if (previousAsyncContext != null) {
previousAsyncContext.onAsyncStart(this);
previousAsyncContext = null;
}
if (!processingAsyncTask) {
processAsyncTask();
}
initiatingThread = null;
}
private synchronized void doDispatch(final Runnable runnable) {
if (dispatched) {
throw UndertowServletMessages.MESSAGES.asyncRequestAlreadyDispatched();
}
dispatched = true;
final HttpServletRequestImpl request = servletRequestContext.getOriginalRequest();
addAsyncTask(new Runnable() {
@Override
public void run() {
request.asyncRequestDispatched();
runnable.run();
}
});
if (timeoutKey != null) {
timeoutKey.remove();
}
}
private final class TimeoutTask implements Runnable {
@Override
public void run() {
synchronized (AsyncContextImpl.this) {
if (!dispatched) {
UndertowServletLogger.REQUEST_LOGGER.debug("Async request timed out");
onAsyncTimeout();
if (!dispatched) {
if(!getResponse().isCommitted()) {
//servlet
try {
if (servletResponse instanceof HttpServletResponse) {
((HttpServletResponse) servletResponse).sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
} else {
servletRequestContext.getOriginalResponse().sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}
} catch (IOException e) {
UndertowLogger.REQUEST_IO_LOGGER.ioException(e);
}
} else {
//not much we can do, just break the connection
IoUtils.safeClose(exchange.getConnection());
}
if (!dispatched) {
complete();
}
}
}
}
}
}
private synchronized void processAsyncTask() {
if (!initialRequestDone) {
return;
}
updateTimeout();
final Runnable task = asyncTaskQueue.poll();
if (task != null) {
processingAsyncTask = true;
asyncExecutor().execute(new TaskDispatchRunnable(task));
} else {
processingAsyncTask = false;
}
}
/**
* Adds a task to be run to the async context. These tasks are run one at a time,
* after the initial request is finished. If the request is dispatched before the initial
* request is complete then these tasks will not be run
* <p/>
* <p/>
* This method is intended to be used to queue read and write tasks for async streams,
* to make sure that multiple threads do not end up working on the same exchange at once
*
* @param runnable The runnable
*/
public synchronized void addAsyncTask(final Runnable runnable) {
asyncTaskQueue.add(runnable);
if (!processingAsyncTask) {
processAsyncTask();
}
}
private class TaskDispatchRunnable implements Runnable {
private final Runnable task;
private TaskDispatchRunnable(final Runnable task) {
this.task = task;
}
@Override
public void run() {
try {
task.run();
} finally {
processAsyncTask();
}
}
}
private void onAsyncComplete() {
final boolean setupRequired = ServletRequestContext.current() == null;
ThreadSetupAction.Handle handle = null;
if (setupRequired) {
handle = servletRequestContext.getDeployment().getThreadSetupAction().setup(exchange);
}
try {
//now run request listeners
setupRequestContext(setupRequired);
try {
for (final BoundAsyncListener listener : asyncListeners) {
AsyncEvent event = new AsyncEvent(this, listener.servletRequest, listener.servletResponse);
try {
listener.asyncListener.onComplete(event);
} catch (IOException e) {
UndertowServletLogger.REQUEST_LOGGER.ioExceptionDispatchingAsyncEvent(e);
}
}
} finally {
tearDownRequestContext(setupRequired);
}
} finally {
if (setupRequired) {
handle.tearDown();
}
}
}
private void onAsyncTimeout() {
final boolean setupRequired = ServletRequestContext.current() == null;
ThreadSetupAction.Handle handle = null;
if (setupRequired) {
handle = servletRequestContext.getDeployment().getThreadSetupAction().setup(exchange);
}
try {
//now run request listeners
setupRequestContext(setupRequired);
try {
for (final BoundAsyncListener listener : asyncListeners) {
AsyncEvent event = new AsyncEvent(this, listener.servletRequest, listener.servletResponse);
try {
listener.asyncListener.onTimeout(event);
} catch (IOException e) {
UndertowServletLogger.REQUEST_LOGGER.ioExceptionDispatchingAsyncEvent(e);
}
}
} finally {
tearDownRequestContext(setupRequired);
}
} finally {
if (setupRequired) {
handle.tearDown();
}
}
}
private void onAsyncStart(AsyncContext newAsyncContext) {
final boolean setupRequired = ServletRequestContext.current() == null;
ThreadSetupAction.Handle handle = null;
if (setupRequired) {
handle = servletRequestContext.getDeployment().getThreadSetupAction().setup(exchange);
}
try {
//now run request listeners
setupRequestContext(setupRequired);
try {
for (final BoundAsyncListener listener : asyncListeners) {
//make sure we use the new async context
AsyncEvent event = new AsyncEvent(newAsyncContext, listener.servletRequest, listener.servletResponse);
try {
listener.asyncListener.onStartAsync(event);
} catch (IOException e) {
UndertowServletLogger.REQUEST_LOGGER.ioExceptionDispatchingAsyncEvent(e);
}
}
} finally {
tearDownRequestContext(setupRequired);
}
} finally {
if (setupRequired) {
handle.tearDown();
}
}
}
private void onAsyncError(Throwable t) {
final boolean setupRequired = ServletRequestContext.current() == null;
ThreadSetupAction.Handle handle = null;
if (setupRequired) {
handle = servletRequestContext.getDeployment().getThreadSetupAction().setup(exchange);
}
try {
//now run request listeners
setupRequestContext(setupRequired);
try {
for (final BoundAsyncListener listener : asyncListeners) {
AsyncEvent event = new AsyncEvent(this, listener.servletRequest, listener.servletResponse, t);
try {
listener.asyncListener.onError(event);
} catch (IOException e) {
UndertowServletLogger.REQUEST_LOGGER.ioExceptionDispatchingAsyncEvent(e);
}
}
} finally {
tearDownRequestContext(setupRequired);
}
} finally {
if (setupRequired) {
handle.tearDown();
}
}
}
private void setupRequestContext(final boolean setupRequired) {
if (setupRequired) {
servletRequestContext.getDeployment().getApplicationListeners().requestInitialized(servletRequest);
ServletRequestContext.setCurrentRequestContext(servletRequestContext);
}
}
private void tearDownRequestContext(final boolean setupRequired) {
if (setupRequired) {
servletRequestContext.getDeployment().getApplicationListeners().requestDestroyed(servletRequest);
ServletRequestContext.clearCurrentServletAttachments();
}
}
private final class BoundAsyncListener {
final AsyncListener asyncListener;
final ServletRequest servletRequest;
final ServletResponse servletResponse;
private BoundAsyncListener(final AsyncListener asyncListener, final ServletRequest servletRequest, final ServletResponse servletResponse) {
this.asyncListener = asyncListener;
this.servletRequest = servletRequest;
this.servletResponse = servletResponse;
}
}
}