    001// Copyright 2010, 2013 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007// http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.internal.services.assets;
    016
    017import org.apache.tapestry5.commons.Resource;
    018import org.apache.tapestry5.http.services.Request;
    019import org.apache.tapestry5.http.services.Response;
    020import org.apache.tapestry5.internal.services.ResourceStreamer;
    021import org.apache.tapestry5.services.AssetSource;
    022import org.apache.tapestry5.services.ClasspathAssetAliasManager;
    023import org.apache.tapestry5.services.ClasspathAssetProtectionRule;
    024import org.apache.tapestry5.services.assets.AssetRequestHandler;
    025
    026import java.io.IOException;
    027
    028/**
    029 * A handler for asset requests for classpath assets (within a specific folder).
    030 * Each mapping of the {@link ClasspathAssetAliasManager} gets one of these.
    031 *
    032 * @since 5.2.0
    033 */
    034public class ClasspathAssetRequestHandler implements AssetRequestHandler
    035{
    036    private final ResourceStreamer streamer;
    037
    038    private final AssetSource assetSource;
    039
    040    private final String baseFolder;
    041
    042    private final ClasspathAssetProtectionRule classpathAssetProtectionRule;
    043
    044    public ClasspathAssetRequestHandler(ResourceStreamer streamer,
    045                                        AssetSource assetSource, String baseFolder,
    046                                        ClasspathAssetProtectionRule classpathAssetProtectionRule)
    047    {
    048        this.streamer = streamer;
    049        this.assetSource = assetSource;
    050        this.baseFolder = baseFolder;
    051        this.classpathAssetProtectionRule = classpathAssetProtectionRule;
    052    }
    053
    054    public boolean handleAssetRequest(Request request, Response response, String extraPath) throws IOException
    055    {
    056        ChecksumPath path = new ChecksumPath(streamer, baseFolder, extraPath);
    057
    058        final boolean handled;
    059        if (classpathAssetProtectionRule.block(path.resourcePath))
    060        {
    061            handled = false;
    062        }
    063        else
    064        {
    065            Resource resource = assetSource.resourceForPath(path.resourcePath);
    066
    067            handled = path.stream(resource);
    068        }
    069        return handled;
    070    }
    071}