001/*
002    Licensed to the Apache Software Foundation (ASF) under one
003    or more contributor license agreements.  See the NOTICE file
004    distributed with this work for additional information
005    regarding copyright ownership.  The ASF licenses this file
006    to you under the Apache License, Version 2.0 (the
007    "License"); you may not use this file except in compliance
008    with the License.  You may obtain a copy of the License at
009
010       http://www.apache.org/licenses/LICENSE-2.0
011
012    Unless required by applicable law or agreed to in writing,
013    software distributed under the License is distributed on an
014    "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015    KIND, either express or implied.  See the License for the
016    specific language governing permissions and limitations
017    under the License.
018 */
019package org.apache.wiki.api.spi;
020
021import org.apache.wiki.api.core.Engine;
022import org.apache.wiki.api.core.Session;
023
024import javax.servlet.http.HttpServletRequest;
025
026
027/**
028 * SPI used to locate and provide {@link Session} instances.
029 */
030public interface SessionSPI {
031
032    /**
033     * Removes the wiki session associated with the user's HTTP request from the cache of wiki sessions, typically as part of a logout process.
034     *
035     * @param engine the wiki engine
036     * @param request the users's HTTP request
037     */
038    void remove( Engine engine, HttpServletRequest request );
039
040    /**
041     * <p>Returns the Session object associated with the current HTTP request. If not found, one is created.
042     * This method is guaranteed to always return a Session, although the authentication status is unpredictable until the user
043     * attempts to log in. If the servlet request parameter is <code>null</code>, a synthetic {@link #guest(Engine)} is
044     * returned.</p>
045     * <p>When a session is created, this method attaches a WikiEventListener to the GroupManager, UserManager and AuthenticationManager,
046     * so that changes to users, groups, logins, etc. are detected automatically.</p>
047     *
048     * @param engine the engine
049     * @param request the servlet request object
050     * @return the existing (or newly created) session
051     */
052    Session find( Engine engine, HttpServletRequest request );
053
054    /**
055     * Creates a new "guest" session containing a single user Principal {@code org.apache.wiki.auth.WikiPrincipal#GUEST}, plus the role
056     * principals {@code Role#ALL} and {@code Role#ANONYMOUS}. This method also adds the session as a listener for GroupManager,
057     * AuthenticationManager and UserManager events.
058     *
059     * @param engine the wiki engine
060     * @return the guest wiki session
061     */
062    Session guest( Engine engine );
063
064}