// Copyright 2011 The Apache Software Foundation
//
// Licensed 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.tapestry5.internal.services.assets;
import java.io.BufferedInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.util.Map;
import org.apache.tapestry5.internal.TapestryInternalUtils;
import org.apache.tapestry5.ioc.Resource;
import org.apache.tapestry5.services.assets.CompressionAnalyzer;
import org.apache.tapestry5.services.assets.CompressionStatus;
import org.apache.tapestry5.services.assets.ContentTypeAnalyzer;
import org.apache.tapestry5.services.assets.ResourceTransformer;
import org.apache.tapestry5.services.assets.StreamableResource;
import org.apache.tapestry5.services.assets.StreamableResourceProcessing;
import org.apache.tapestry5.services.assets.StreamableResourceSource;
public class StreamableResourceSourceImpl implements StreamableResourceSource
{
private final Map<String, ResourceTransformer> configuration;
private final ContentTypeAnalyzer contentTypeAnalyzer;
private final CompressionAnalyzer compressionAnalyzer;
private final ResourceChangeTracker resourceChangeTracker;
public StreamableResourceSourceImpl(Map<String, ResourceTransformer> configuration,
ContentTypeAnalyzer contentTypeAnalyzer, CompressionAnalyzer compressionAnalyzer,
ResourceChangeTracker resourceChangeTracker)
{
this.configuration = configuration;
this.contentTypeAnalyzer = contentTypeAnalyzer;
this.compressionAnalyzer = compressionAnalyzer;
this.resourceChangeTracker = resourceChangeTracker;
}
public StreamableResource getStreamableResource(Resource baseResource, StreamableResourceProcessing processing)
throws IOException
{
assert baseResource != null;
URL url = baseResource.toURL();
if (url == null)
throw new IOException(String.format("Resource %s does not exist.", baseResource));
String fileSuffix = TapestryInternalUtils.toFileSuffix(baseResource.getFile());
// Optionally, transform the resource. The main driver for this is to allow
// for libraries like LessJS (http://lesscss.org/) or
// http://jashkenas.github.com/coffee-script/
ResourceTransformer rt = configuration.get(fileSuffix);
InputStream buffered = new BufferedInputStream(url.openStream());
InputStream transformed = rt == null ? buffered : rt.transform(buffered);
BytestreamCache bytestreamCache = readStream(transformed);
transformed.close();
buffered.close();
String contentType = contentTypeAnalyzer.getContentType(baseResource);
boolean compressable = compressionAnalyzer.isCompressable(contentType);
long lastModified = resourceChangeTracker.trackResource(baseResource);
return new StreamableResourceImpl(contentType, compressable ? CompressionStatus.COMPRESSABLE
: CompressionStatus.NOT_COMPRESSABLE, lastModified, bytestreamCache);
}
private BytestreamCache readStream(InputStream stream) throws IOException
{
ByteArrayOutputStream bos = new ByteArrayOutputStream();
TapestryInternalUtils.copy(stream, bos);
stream.close();
return new BytestreamCache(bos);
}
}