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/*
*
* 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.qpid.restapi;
import java.io.IOException;
/**
* A Server represents a handler that runs within a Web server, which is invoked to process HTTP exchanges.
* Servers receive and respond to requests from Web clients that are encapsulated into HttpTransactions.
* <p>
* The Server and HttpTransaction interfaces are intended to provide abstractions to enable the "business logic" to
* be isolated from the actual Web Server implementation choice, so for example a concrete HttpTransaction implementation
* could be created by wrapping a com.sun.net.httpserver.HttpExchange, but equally another implementation could wrap
* javax.servlet.http.HttpServletRequest and javax.servlet.http.HttpServletResponse so for example an HttpServlet
* could delegate to a Server instance passing the HttpTransaction it constructed from the HttpServletRequest and
* HttpServletResponse.
*
* @author Fraser Adams
*/
public interface Server
{
/**
* Called by the Web Server to allow a Server to handle a GET request.
* <p>
* The GET method should be safe, that is, without any side effects for which users are held responsible. For
* example, most form queries have no side effects. If a client request is intended to change stored data, the
* request should use some other HTTP method.
* <p>
* The GET method should also be idempotent, meaning that it can be safely repeated. Sometimes making a method safe
* also makes it idempotent. For example, repeating queries is both safe and idempotent, but buying a product online
* or modifying data is neither safe nor idempotent.
*
* @param tx the HttpTransaction containing the request from the client and used to send the response.
*/
public void doGet(HttpTransaction tx) throws IOException;
/**
* Called by the Web Server to allow a Server to handle a POST request.
* <p>
* The HTTP POST method allows the client to send data of unlimited length to the Web server a single time and is
* useful when posting information such as credit card numbers.
* <p>
* This method does not need to be either safe or idempotent. Operations requested through POST can have side
* effects for which the user can be held accountable, for example, updating stored data or buying items online.
*
* @param tx the HttpTransaction containing the request from the client and used to send the response.
*/
public void doPost(HttpTransaction tx) throws IOException;
/**
* Called by the Web Server to allow a Server to handle a PUT request.
* <p>
* The PUT operation allows a client to place a file on the server and is similar to sending a file by FTP.
* <p>
* This method does not need to be either safe or idempotent. Operations that doPut performs can have side effects
* for which the user can be held accountable. When using this method, it may be useful to save a copy of the
* affected URL in temporary storage.
*
* @param tx the HttpTransaction containing the request from the client and used to send the response.
*/
public void doPut(HttpTransaction tx) throws IOException;
/**
* Called by the Web Server to allow a Server to handle a DELETE request.
* <p>
* The DELETE operation allows a client to remove a document or Web page from the server.
* <p>
* This method does not need to be either safe or idempotent. Operations requested through DELETE can have side
* effects for which users can be held accountable. When using this method, it may be useful to save a copy of the
* affected URL in temporary storage.
*
* @param tx the HttpTransaction containing the request from the client and used to send the response.
*/
public void doDelete(HttpTransaction tx) throws IOException;
}
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