| /* |
| * ==================================================================== |
| * 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. |
| * ==================================================================== |
| * |
| * This software consists of voluntary contributions made by many |
| * individuals on behalf of the Apache Software Foundation. For more |
| * information on the Apache Software Foundation, please see |
| * <http://www.apache.org/>. |
| * |
| */ |
| package org.apache.hc.core5.http.io.support; |
| |
| import java.io.IOException; |
| |
| import org.apache.hc.core5.annotation.Contract; |
| import org.apache.hc.core5.annotation.ThreadingBehavior; |
| import org.apache.hc.core5.http.ClassicHttpRequest; |
| import org.apache.hc.core5.http.ClassicHttpResponse; |
| import org.apache.hc.core5.http.Header; |
| import org.apache.hc.core5.http.HeaderElements; |
| import org.apache.hc.core5.http.HttpEntity; |
| import org.apache.hc.core5.http.HttpException; |
| import org.apache.hc.core5.http.HttpHeaders; |
| import org.apache.hc.core5.http.HttpResponse; |
| import org.apache.hc.core5.http.HttpStatus; |
| import org.apache.hc.core5.http.io.HttpFilterChain; |
| import org.apache.hc.core5.http.io.HttpFilterHandler; |
| import org.apache.hc.core5.http.message.BasicClassicHttpResponse; |
| import org.apache.hc.core5.http.protocol.HttpContext; |
| |
| /** |
| * HttpServerExpectationFilter add support for the Expect-Continue handshake |
| * to the request processing pipeline. |
| * |
| * @since 5.0 |
| */ |
| @Contract(threading = ThreadingBehavior.STATELESS) |
| public class HttpServerExpectationFilter implements HttpFilterHandler { |
| |
| /** |
| * Verifies the HTTP request and decides whether it meets server expectations and the request |
| * processing can continue. |
| * |
| * @param request the incoming HTTP request. |
| * @param context the actual execution context. |
| * @return {@code true} if the request meets expectations or {@code false} otherwise. |
| */ |
| protected boolean verify(final ClassicHttpRequest request, final HttpContext context) throws HttpException { |
| return true; |
| } |
| |
| /** |
| * Generates response content entity for the final HTTP response with an error status |
| * representing the cause of expectation failure. |
| * |
| * @param expectationFailed the final HTTP response. |
| * @return the content entity for the final HTTP response with an error status |
| * representing the cause of expectation failure. |
| */ |
| protected HttpEntity generateResponseContent(final HttpResponse expectationFailed) throws HttpException { |
| return null; |
| } |
| |
| @Override |
| public final void handle( |
| final ClassicHttpRequest request, |
| final HttpFilterChain.ResponseTrigger responseTrigger, |
| final HttpContext context, |
| final HttpFilterChain chain) throws HttpException, IOException { |
| final Header expect = request.getFirstHeader(HttpHeaders.EXPECT); |
| final boolean expectContinue = expect != null && HeaderElements.CONTINUE.equalsIgnoreCase(expect.getValue()); |
| if (expectContinue) { |
| final boolean verified = verify(request, context); |
| if (verified) { |
| responseTrigger.sendInformation(new BasicClassicHttpResponse(HttpStatus.SC_CONTINUE)); |
| } else { |
| final ClassicHttpResponse expectationFailed = new BasicClassicHttpResponse(HttpStatus.SC_EXPECTATION_FAILED); |
| final HttpEntity responseContent = generateResponseContent(expectationFailed); |
| expectationFailed.setEntity(responseContent); |
| responseTrigger.submitResponse(expectationFailed); |
| return; |
| } |
| } |
| chain.proceed(request, responseTrigger, context); |
| } |
| } |