michael@0: /*
michael@0:  * ====================================================================
michael@0:  * Licensed to the Apache Software Foundation (ASF) under one
michael@0:  * or more contributor license agreements.  See the NOTICE file
michael@0:  * distributed with this work for additional information
michael@0:  * regarding copyright ownership.  The ASF licenses this file
michael@0:  * to you under the Apache License, Version 2.0 (the
michael@0:  * "License"); you may not use this file except in compliance
michael@0:  * with the License.  You may obtain a copy of the License at
michael@0:  *
michael@0:  *   http://www.apache.org/licenses/LICENSE-2.0
michael@0:  *
michael@0:  * Unless required by applicable law or agreed to in writing,
michael@0:  * software distributed under the License is distributed on an
michael@0:  * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
michael@0:  * KIND, either express or implied.  See the License for the
michael@0:  * specific language governing permissions and limitations
michael@0:  * under the License.
michael@0:  * ====================================================================
michael@0:  *
michael@0:  * This software consists of voluntary contributions made by many
michael@0:  * individuals on behalf of the Apache Software Foundation.  For more
michael@0:  * information on the Apache Software Foundation, please see
michael@0:  * <http://www.apache.org/>.
michael@0:  *
michael@0:  */
michael@0: 
michael@0: package ch.boye.httpclientandroidlib.protocol;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.HttpException;
michael@0: import ch.boye.httpclientandroidlib.HttpRequest;
michael@0: import ch.boye.httpclientandroidlib.HttpResponse;
michael@0: 
michael@0: /**
michael@0:  * Defines an interface to verify whether an incoming HTTP request meets
michael@0:  * the target server's expectations.
michael@0:  *<p>
michael@0:  * The Expect request-header field is used to indicate that particular
michael@0:  * server behaviors are required by the client.
michael@0:  *</p>
michael@0:  *<pre>
michael@0:  *    Expect       =  "Expect" ":" 1#expectation
michael@0:  *
michael@0:  *    expectation  =  "100-continue" | expectation-extension
michael@0:  *    expectation-extension =  token [ "=" ( token | quoted-string )
michael@0:  *                             *expect-params ]
michael@0:  *    expect-params =  ";" token [ "=" ( token | quoted-string ) ]
michael@0:  *</pre>
michael@0:  *<p>
michael@0:  * A server that does not understand or is unable to comply with any of
michael@0:  * the expectation values in the Expect field of a request MUST respond
michael@0:  * with appropriate error status. The server MUST respond with a 417
michael@0:  * (Expectation Failed) status if any of the expectations cannot be met
michael@0:  * or, if there are other problems with the request, some other 4xx
michael@0:  * status.
michael@0:  *</p>
michael@0:  *
michael@0:  * @since 4.0
michael@0:  */
michael@0: public interface HttpExpectationVerifier {
michael@0: 
michael@0:     /**
michael@0:      * Verifies whether the given request meets the server's expectations.
michael@0:      * <p>
michael@0:      * If the request fails to meet particular criteria, this method can
michael@0:      * trigger a terminal response back to the client by setting the status
michael@0:      * code of the response object to a value greater or equal to
michael@0:      * <code>200</code>. In this case the client will not have to transmit
michael@0:      * the request body. If the request meets expectations this method can
michael@0:      * terminate without modifying the response object. Per default the status
michael@0:      * code of the response object will be set to <code>100</code>.
michael@0:      *
michael@0:      * @param request the HTTP request.
michael@0:      * @param response the HTTP response.
michael@0:      * @param context the HTTP context.
michael@0:      * @throws HttpException in case of an HTTP protocol violation.
michael@0:      */
michael@0:     void verify(HttpRequest request, HttpResponse response, HttpContext context)
michael@0:             throws HttpException;
michael@0: 
michael@0: }