AsyncContextImpl.java
/*
* 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.catalina.core;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicBoolean;
import javax.naming.NamingException;
import javax.servlet.AsyncContext;
import javax.servlet.AsyncEvent;
import javax.servlet.AsyncListener;
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 org.apache.catalina.AsyncDispatcher;
import org.apache.catalina.Context;
import org.apache.catalina.Globals;
import org.apache.catalina.Host;
import org.apache.catalina.Valve;
import org.apache.catalina.connector.Request;
import org.apache.coyote.ActionCode;
import org.apache.coyote.AsyncContextCallback;
import org.apache.coyote.RequestInfo;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.ExceptionUtils;
import org.apache.tomcat.util.buf.UDecoder;
import org.apache.tomcat.util.res.StringManager;
public class AsyncContextImpl implements AsyncContext, AsyncContextCallback {
private static final Log log = LogFactory.getLog(AsyncContextImpl.class);
protected static final StringManager sm = StringManager.getManager(AsyncContextImpl.class);
/*
* When a request uses a sequence of multiple start(); dispatch() with non-container threads it is possible for a
* previous dispatch() to interfere with a following start(). This lock prevents that from happening. It is a
* dedicated object as user code may lock on the AsyncContext so if container code also locks on that object
* deadlocks may occur.
*/
private final Object asyncContextLock = new Object();
private volatile ServletRequest servletRequest = null;
private volatile ServletResponse servletResponse = null;
private final List<AsyncListenerWrapper> listeners = new ArrayList<>();
private boolean hasOriginalRequestAndResponse = true;
private volatile Runnable dispatch = null;
private Context context = null;
// Default of 30000 (30s) is set by the connector
private long timeout = -1;
private AsyncEvent event = null;
private volatile Request request;
private final AtomicBoolean hasErrorProcessingStarted = new AtomicBoolean(false);
private final AtomicBoolean hasOnErrorReturned = new AtomicBoolean(false);
public AsyncContextImpl(Request request) {
if (log.isTraceEnabled()) {
logDebug("Constructor");
}
this.request = request;
}
@Override
public void complete() {
if (log.isTraceEnabled()) {
logDebug("complete ");
}
check();
request.getCoyoteRequest().action(ActionCode.ASYNC_COMPLETE, null);
}
@Override
public void fireOnComplete() {
if (log.isTraceEnabled()) {
log.trace(sm.getString("asyncContextImpl.fireOnComplete"));
}
List<AsyncListenerWrapper> listenersCopy = new ArrayList<>(listeners);
ClassLoader oldCL = context.bind(Globals.IS_SECURITY_ENABLED, null);
try {
for (AsyncListenerWrapper listener : listenersCopy) {
try {
listener.fireOnComplete(event);
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
log.warn(sm.getString("asyncContextImpl.onCompleteError", listener.getClass().getName()), t);
}
}
} finally {
context.fireRequestDestroyEvent(request.getRequest());
clearServletRequestResponse();
context.unbind(Globals.IS_SECURITY_ENABLED, oldCL);
}
}
public boolean timeout() {
AtomicBoolean result = new AtomicBoolean();
request.getCoyoteRequest().action(ActionCode.ASYNC_TIMEOUT, result);
// Avoids NPEs during shutdown. A call to recycle will null this field.
Context context = this.context;
if (result.get()) {
if (log.isTraceEnabled()) {
log.trace(sm.getString("asyncContextImpl.fireOnTimeout"));
}
ClassLoader oldCL = context.bind(false, null);
try {
List<AsyncListenerWrapper> listenersCopy = new ArrayList<>(listeners);
for (AsyncListenerWrapper listener : listenersCopy) {
try {
listener.fireOnTimeout(event);
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
log.warn(sm.getString("asyncContextImpl.onTimeoutError", listener.getClass().getName()), t);
}
}
request.getCoyoteRequest().action(ActionCode.ASYNC_IS_TIMINGOUT, result);
} finally {
context.unbind(false, oldCL);
}
}
return !result.get();
}
@Override
public void dispatch() {
check();
String path;
String cpath;
ServletRequest servletRequest = getRequest();
if (servletRequest instanceof HttpServletRequest) {
HttpServletRequest sr = (HttpServletRequest) servletRequest;
path = sr.getRequestURI();
cpath = sr.getContextPath();
} else {
path = request.getRequestURI();
cpath = request.getContextPath();
}
if (cpath.length() > 1) {
path = path.substring(cpath.length());
}
if (!context.getDispatchersUseEncodedPaths()) {
path = UDecoder.URLDecode(path, StandardCharsets.UTF_8);
}
dispatch(path);
}
@Override
public void dispatch(String path) {
check();
dispatch(getRequest().getServletContext(), path);
}
@Override
public void dispatch(ServletContext servletContext, String path) {
synchronized (asyncContextLock) {
if (log.isTraceEnabled()) {
logDebug("dispatch ");
}
check();
if (dispatch != null) {
throw new IllegalStateException(sm.getString("asyncContextImpl.dispatchingStarted"));
}
if (request.getAttribute(ASYNC_REQUEST_URI) == null) {
request.setAttribute(ASYNC_REQUEST_URI, request.getRequestURI());
request.setAttribute(ASYNC_CONTEXT_PATH, request.getContextPath());
request.setAttribute(ASYNC_SERVLET_PATH, request.getServletPath());
request.setAttribute(ASYNC_PATH_INFO, request.getPathInfo());
request.setAttribute(ASYNC_QUERY_STRING, request.getQueryString());
}
final RequestDispatcher requestDispatcher = servletContext.getRequestDispatcher(path);
if (!(requestDispatcher instanceof AsyncDispatcher)) {
throw new UnsupportedOperationException(sm.getString("asyncContextImpl.noAsyncDispatcher"));
}
final AsyncDispatcher applicationDispatcher = (AsyncDispatcher) requestDispatcher;
final ServletRequest servletRequest = getRequest();
final ServletResponse servletResponse = getResponse();
this.dispatch = new AsyncRunnable(request, applicationDispatcher, servletRequest, servletResponse);
this.request.getCoyoteRequest().action(ActionCode.ASYNC_DISPATCH, null);
clearServletRequestResponse();
}
}
@Override
public ServletRequest getRequest() {
check();
if (servletRequest == null) {
throw new IllegalStateException(sm.getString("asyncContextImpl.request.ise"));
}
return servletRequest;
}
@Override
public ServletResponse getResponse() {
check();
if (servletResponse == null) {
throw new IllegalStateException(sm.getString("asyncContextImpl.response.ise"));
}
return servletResponse;
}
@Override
public void start(final Runnable run) {
if (log.isTraceEnabled()) {
logDebug("start ");
}
check();
Runnable wrapper = new RunnableWrapper(run, context, this.request.getCoyoteRequest());
this.request.getCoyoteRequest().action(ActionCode.ASYNC_RUN, wrapper);
}
@Override
public void addListener(AsyncListener listener) {
check();
AsyncListenerWrapper wrapper = new AsyncListenerWrapper();
wrapper.setListener(listener);
listeners.add(wrapper);
}
@Override
public void addListener(AsyncListener listener, ServletRequest servletRequest, ServletResponse servletResponse) {
check();
AsyncListenerWrapper wrapper = new AsyncListenerWrapper();
wrapper.setListener(listener);
wrapper.setServletRequest(servletRequest);
wrapper.setServletResponse(servletResponse);
listeners.add(wrapper);
}
@SuppressWarnings("unchecked")
@Override
public <T extends AsyncListener> T createListener(Class<T> clazz) throws ServletException {
check();
T listener = null;
try {
listener = (T) context.getInstanceManager().newInstance(clazz.getName(), clazz.getClassLoader());
} catch (ReflectiveOperationException | NamingException e) {
ServletException se = new ServletException(e);
throw se;
} catch (Exception e) {
ExceptionUtils.handleThrowable(e.getCause());
ServletException se = new ServletException(e);
throw se;
}
return listener;
}
public void recycle() {
if (log.isTraceEnabled()) {
logDebug("recycle ");
}
context = null;
dispatch = null;
event = null;
hasOriginalRequestAndResponse = true;
listeners.clear();
request = null;
clearServletRequestResponse();
timeout = -1;
hasErrorProcessingStarted.set(false);
hasOnErrorReturned.set(false);
}
private void clearServletRequestResponse() {
servletRequest = null;
servletResponse = null;
}
public boolean isStarted() {
AtomicBoolean result = new AtomicBoolean(false);
Request request = this.request;
check();
request.getCoyoteRequest().action(ActionCode.ASYNC_IS_STARTED, result);
return result.get();
}
public void setStarted(Context context, ServletRequest request, ServletResponse response,
boolean originalRequestResponse) {
synchronized (asyncContextLock) {
this.request.getCoyoteRequest().action(ActionCode.ASYNC_START, this);
this.context = context;
context.incrementInProgressAsyncCount();
this.servletRequest = request;
this.servletResponse = response;
this.hasOriginalRequestAndResponse = originalRequestResponse;
this.event = new AsyncEvent(this, request, response);
List<AsyncListenerWrapper> listenersCopy = new ArrayList<>(listeners);
listeners.clear();
if (log.isTraceEnabled()) {
log.trace(sm.getString("asyncContextImpl.fireOnStartAsync"));
}
for (AsyncListenerWrapper listener : listenersCopy) {
try {
listener.fireOnStartAsync(event);
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
log.warn(sm.getString("asyncContextImpl.onStartAsyncError", listener.getClass().getName()), t);
}
}
}
}
@Override
public boolean hasOriginalRequestAndResponse() {
check();
return hasOriginalRequestAndResponse;
}
protected void doInternalDispatch() throws ServletException, IOException {
if (log.isTraceEnabled()) {
logDebug("intDispatch");
}
try {
Runnable runnable = dispatch;
dispatch = null;
runnable.run();
if (!request.isAsync()) {
fireOnComplete();
}
} catch (RuntimeException x) {
// doInternalComplete(true);
if (x.getCause() instanceof ServletException) {
throw (ServletException) x.getCause();
}
if (x.getCause() instanceof IOException) {
throw (IOException) x.getCause();
}
throw new ServletException(x);
}
}
@Override
public long getTimeout() {
check();
return timeout;
}
@Override
public void setTimeout(long timeout) {
check();
this.timeout = timeout;
request.getCoyoteRequest().action(ActionCode.ASYNC_SETTIMEOUT, Long.valueOf(timeout));
}
@Override
public boolean isAvailable() {
Context context = this.context;
if (context == null) {
return false;
}
return context.getState().isAvailable();
}
public void setErrorState(Throwable t, boolean fireOnError) {
if (!hasErrorProcessingStarted.compareAndSet(false, true)) {
// Skip duplicate error processing
return;
}
if (t != null) {
request.setAttribute(RequestDispatcher.ERROR_EXCEPTION, t);
}
request.getCoyoteRequest().action(ActionCode.ASYNC_ERROR, null);
if (fireOnError) {
if (log.isTraceEnabled()) {
log.trace(sm.getString("asyncContextImpl.fireOnError"));
}
AsyncEvent errorEvent =
new AsyncEvent(event.getAsyncContext(), event.getSuppliedRequest(), event.getSuppliedResponse(), t);
List<AsyncListenerWrapper> listenersCopy = new ArrayList<>(listeners);
for (AsyncListenerWrapper listener : listenersCopy) {
try {
listener.fireOnError(errorEvent);
} catch (Throwable t2) {
ExceptionUtils.handleThrowable(t2);
log.warn(sm.getString("asyncContextImpl.onErrorError", listener.getClass().getName()), t2);
} finally {
hasOnErrorReturned.set(true);
}
}
}
AtomicBoolean result = new AtomicBoolean();
request.getCoyoteRequest().action(ActionCode.ASYNC_IS_ERROR, result);
if (result.get()) {
// No listener called dispatch() or complete(). This is an error.
// SRV.2.3.3.3 (search for "error dispatch")
// Take a local copy to avoid threading issues if another thread
// clears this (can happen during error handling with non-container
// threads)
ServletResponse servletResponse = this.servletResponse;
if (servletResponse instanceof HttpServletResponse) {
((HttpServletResponse) servletResponse).setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
}
Host host = (Host) context.getParent();
Valve stdHostValve = host.getPipeline().getBasic();
if (stdHostValve instanceof StandardHostValve) {
((StandardHostValve) stdHostValve).throwable(request, request.getResponse(), t);
}
request.getCoyoteRequest().action(ActionCode.ASYNC_IS_ERROR, result);
if (result.get()) {
// Still in the error state. The error page did not call
// complete() or dispatch(). Complete the async processing.
complete();
}
} else if (request.isAsyncDispatching()) {
/*
* AsyncListener.onError() called dispatch. Clear the error state on the response else the dispatch will
* trigger error page handling.
*/
request.getResponse().resetError();
}
}
@Override
public void incrementInProgressAsyncCount() {
context.incrementInProgressAsyncCount();
}
@Override
public void decrementInProgressAsyncCount() {
context.decrementInProgressAsyncCount();
}
private void logDebug(String method) {
String rHashCode;
String crHashCode;
String rpHashCode;
String stage;
StringBuilder uri = new StringBuilder();
if (request == null) {
rHashCode = "null";
crHashCode = "null";
rpHashCode = "null";
stage = "-";
uri.append("N/A");
} else {
rHashCode = Integer.toHexString(request.hashCode());
org.apache.coyote.Request coyoteRequest = request.getCoyoteRequest();
if (coyoteRequest == null) {
crHashCode = "null";
rpHashCode = "null";
stage = "-";
} else {
crHashCode = Integer.toHexString(coyoteRequest.hashCode());
RequestInfo rp = coyoteRequest.getRequestProcessor();
if (rp == null) {
rpHashCode = "null";
stage = "-";
} else {
rpHashCode = Integer.toHexString(rp.hashCode());
stage = Integer.toString(rp.getStage());
}
}
uri.append(request.getRequestURI());
if (request.getQueryString() != null) {
uri.append('?');
uri.append(request.getQueryString());
}
}
String threadName = Thread.currentThread().getName();
int len = threadName.length();
if (len > 20) {
threadName = threadName.substring(len - 20, len);
}
String msg = String.format(
"Req: %1$8s CReq: %2$8s RP: %3$8s Stage: %4$s " +
"Thread: %5$20s State: %6$20s Method: %7$11s URI: %8$s",
rHashCode, crHashCode, rpHashCode, stage, threadName, "N/A", method, uri);
if (log.isTraceEnabled()) {
log.trace(msg, new DebugException());
} else {
log.debug(msg);
}
}
private void check() {
Request request = this.request;
if (request == null) {
// AsyncContext has been recycled and should not be being used
throw new IllegalStateException(sm.getString("asyncContextImpl.requestEnded"));
}
if (hasOnErrorReturned.get() && !request.getCoyoteRequest().isRequestThread()) {
/*
* Non-container thread is trying to use the AsyncContext after an error has occurred and the call to
* AsyncListener.onError() has returned. At this point, the non-container thread should not be trying to use
* the AsyncContext due to possible race conditions.
*/
throw new IllegalStateException(sm.getString("asyncContextImpl.afterOnError"));
}
}
private static class DebugException extends Exception {
private static final long serialVersionUID = 1L;
}
private static class RunnableWrapper implements Runnable {
private final Runnable wrapped;
private final Context context;
private final org.apache.coyote.Request coyoteRequest;
RunnableWrapper(Runnable wrapped, Context ctxt, org.apache.coyote.Request coyoteRequest) {
this.wrapped = wrapped;
this.context = ctxt;
this.coyoteRequest = coyoteRequest;
}
@SuppressWarnings("deprecation")
@Override
public void run() {
ClassLoader oldCL = context.bind(Globals.IS_SECURITY_ENABLED, null);
try {
wrapped.run();
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
context.getLogger().error(sm.getString("asyncContextImpl.asyncRunnableError"), t);
coyoteRequest.setAttribute(RequestDispatcher.ERROR_EXCEPTION, t);
org.apache.coyote.Response coyoteResponse = coyoteRequest.getResponse();
coyoteResponse.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
coyoteResponse.setError();
} finally {
context.unbind(Globals.IS_SECURITY_ENABLED, oldCL);
}
// Since this runnable is not executing as a result of a socket
// event, we need to ensure that any registered dispatches are
// executed.
coyoteRequest.action(ActionCode.DISPATCH_EXECUTE, null);
}
}
private static class AsyncRunnable implements Runnable {
private final AsyncDispatcher applicationDispatcher;
private final Request request;
private final ServletRequest servletRequest;
private final ServletResponse servletResponse;
AsyncRunnable(Request request, AsyncDispatcher applicationDispatcher, ServletRequest servletRequest,
ServletResponse servletResponse) {
this.request = request;
this.applicationDispatcher = applicationDispatcher;
this.servletRequest = servletRequest;
this.servletResponse = servletResponse;
}
@Override
public void run() {
request.getCoyoteRequest().action(ActionCode.ASYNC_DISPATCHED, null);
try {
applicationDispatcher.dispatch(servletRequest, servletResponse);
} catch (Exception e) {
throw new RuntimeException(sm.getString("asyncContextImpl.asyncDispatchError"), e);
}
}
}
}