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The core jetty server artifact.
//
// ========================================================================
// Copyright (c) 1995 Mort Bay Consulting Pty Ltd and others.
//
// This program and the accompanying materials are made available under the
// terms of the Eclipse Public License v. 2.0 which is available at
// https://www.eclipse.org/legal/epl-2.0, or the Apache License, Version 2.0
// which is available at https://www.apache.org/licenses/LICENSE-2.0.
//
// SPDX-License-Identifier: EPL-2.0 OR Apache-2.0
// ========================================================================
//
package org.eclipse.jetty.server.handler;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.Objects;
import java.util.concurrent.CompletableFuture;
import java.util.concurrent.atomic.AtomicReference;
import org.eclipse.jetty.http.HttpField;
import org.eclipse.jetty.http.HttpHeader;
import org.eclipse.jetty.http.HttpHeaderValue;
import org.eclipse.jetty.http.HttpStatus;
import org.eclipse.jetty.http.MimeTypes;
import org.eclipse.jetty.io.Content;
import org.eclipse.jetty.server.FormFields;
import org.eclipse.jetty.server.Handler;
import org.eclipse.jetty.server.Request;
import org.eclipse.jetty.server.Response;
import org.eclipse.jetty.util.Callback;
import org.eclipse.jetty.util.Fields;
import org.eclipse.jetty.util.StringUtil;
public class DelayedHandler extends Handler.Wrapper
{
public DelayedHandler()
{
this(null);
}
public DelayedHandler(Handler handler)
{
super(handler);
}
@Override
public boolean handle(Request request, Response response, Callback callback) throws Exception
{
Handler next = getHandler();
if (next == null)
return false;
boolean contentExpected = false;
String contentType = null;
loop: for (HttpField field : request.getHeaders())
{
HttpHeader header = field.getHeader();
if (header == null)
continue;
switch (header)
{
case CONTENT_TYPE:
contentType = field.getValue();
break;
case CONTENT_LENGTH:
contentExpected = field.getLongValue() > 0;
break;
case TRANSFER_ENCODING:
contentExpected = field.contains(HttpHeaderValue.CHUNKED.asString());
break;
case EXPECT:
if (field.contains(HttpHeaderValue.CONTINUE.asString()))
{
contentExpected = false;
break loop;
}
break;
default:
break;
}
}
MimeTypes.Type mimeType = MimeTypes.getBaseType(contentType);
DelayedProcess delayed = newDelayedProcess(contentExpected, contentType, mimeType, next, request, response, callback);
if (delayed == null)
return next.handle(request, response, callback);
delayed.delay();
return true;
}
protected DelayedProcess newDelayedProcess(boolean contentExpected, String contentType, MimeTypes.Type mimeType, Handler handler, Request request, Response response, Callback callback)
{
// if no content is expected, then no delay
if (!contentExpected)
return null;
// if we are not configured to delay dispatch, then no delay
if (!request.getConnectionMetaData().getHttpConfiguration().isDelayDispatchUntilContent())
return null;
// If there is no known content type, then delay only until content is available
if (mimeType == null)
return new UntilContentDelayedProcess(handler, request, response, callback);
// Otherwise, delay until a known content type is fully read; or if the type is not known then until the content is available
return switch (mimeType)
{
case FORM_ENCODED -> new UntilFormDelayedProcess(handler, request, response, callback, contentType);
default -> new UntilContentDelayedProcess(handler, request, response, callback);
};
}
protected abstract static class DelayedProcess
{
private final Handler _handler;
private final Request _request;
private final Response _response;
private final Callback _callback;
protected DelayedProcess(Handler handler, Request request, Response response, Callback callback)
{
_handler = Objects.requireNonNull(handler);
_request = Objects.requireNonNull(request);
_response = Objects.requireNonNull(response);
_callback = Objects.requireNonNull(callback);
}
protected Handler getHandler()
{
return _handler;
}
protected Request getRequest()
{
return _request;
}
protected Response getResponse()
{
return _response;
}
protected Callback getCallback()
{
return _callback;
}
protected void process()
{
try
{
if (!getHandler().handle(getRequest(), getResponse(), getCallback()))
Response.writeError(getRequest(), getResponse(), getCallback(), HttpStatus.NOT_FOUND_404);
}
catch (Throwable t)
{
Response.writeError(getRequest(), getResponse(), getCallback(), t);
}
}
protected abstract void delay() throws Exception;
}
protected static class UntilContentDelayedProcess extends DelayedProcess
{
public UntilContentDelayedProcess(Handler handler, Request request, Response response, Callback callback)
{
super(handler, request, response, callback);
}
@Override
protected void delay()
{
Content.Chunk chunk = super.getRequest().read();
if (chunk == null)
{
getRequest().demand(this::onContent);
}
else
{
RewindChunkRequest request = new RewindChunkRequest(getRequest(), chunk);
try
{
getHandler().handle(request, getResponse(), getCallback());
}
catch (Throwable x)
{
// Use the wrapped request so that the error handling can
// consume the request content and release the already read chunk.
Response.writeError(request, getResponse(), getCallback(), x);
}
}
}
public void onContent()
{
// We must execute here, because demand callbacks are serialized and process may block on a demand callback
getRequest().getContext().execute(this::process);
}
private static class RewindChunkRequest extends Request.Wrapper
{
private final AtomicReference _chunk;
public RewindChunkRequest(Request wrapped, Content.Chunk chunk)
{
super(wrapped);
_chunk = new AtomicReference<>(chunk);
}
@Override
public Content.Chunk read()
{
Content.Chunk chunk = _chunk.getAndSet(null);
if (chunk != null)
return chunk;
return super.read();
}
}
}
protected static class UntilFormDelayedProcess extends DelayedProcess
{
private final Charset _charset;
public UntilFormDelayedProcess(Handler handler, Request wrapped, Response response, Callback callback, String contentType)
{
super(handler, wrapped, response, callback);
String cs = MimeTypes.getCharsetFromContentType(contentType);
_charset = StringUtil.isEmpty(cs) ? StandardCharsets.UTF_8 : Charset.forName(cs);
}
@Override
protected void delay()
{
CompletableFuture futureFormFields = FormFields.from(getRequest(), _charset);
// if we are done already, then we are still in the scope of the original process call and can
// process directly, otherwise we must execute a call to process as we are within a serialized
// demand callback.
futureFormFields.whenComplete(futureFormFields.isDone() ? this::process : this::executeProcess);
}
private void process(Fields fields, Throwable x)
{
if (x == null)
super.process();
else
Response.writeError(getRequest(), getResponse(), getCallback(), x);
}
private void executeProcess(Fields fields, Throwable x)
{
if (x == null)
// We must execute here as even though we have consumed all the input, we are probably
// invoked in a demand runnable that is serialized with any write callbacks that might be done in process
getRequest().getContext().execute(super::process);
else
Response.writeError(getRequest(), getResponse(), getCallback(), x);
}
}
}