/*
* 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.sling.rewriter.impl;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.Writer;
import java.util.Iterator;
import java.util.List;
import org.apache.sling.adapter.annotations.Adaptable;
import org.apache.sling.adapter.annotations.Adapter;
import org.apache.sling.api.SlingException;
import org.apache.sling.api.SlingHttpServletRequest;
import org.apache.sling.api.SlingHttpServletResponse;
import org.apache.sling.api.wrappers.SlingHttpServletResponseWrapper;
import org.apache.sling.rewriter.ProcessingContext;
import org.apache.sling.rewriter.Processor;
import org.apache.sling.rewriter.ProcessorConfiguration;
import org.apache.sling.rewriter.ProcessorManager;
import org.xml.sax.ContentHandler;
/**
* This response is used to pass the output through the rewriter pipeline.
*/
@Adaptable(adaptableClass=SlingHttpServletResponse.class, adapters={
@Adapter(value=ContentHandler.class,
condition="When the response is being processed through the Sling Rewriter filter.")
})
class RewriterResponse
extends SlingHttpServletResponseWrapper {
/** The current request. */
private final SlingHttpServletRequest request;
/** The processor. */
private Processor processor;
/** wrapped rewriter/servlet writer */
private PrintWriter writer;
/** response content type */
private String contentType;
/** The processor manager. */
private final ProcessorManager processorManager;
/**
* Initializes a new instance.
* @param request The sling request.
* @param delegatee The SlingHttpServletResponse wrapped by this instance.
*/
public RewriterResponse(SlingHttpServletRequest request,
SlingHttpServletResponse delegatee,
ProcessorManager processorManager) {
super(delegatee);
this.processorManager = processorManager;
this.request = request;
}
/**
* @see javax.servlet.ServletResponseWrapper#setContentType(java.lang.String)
*/
public void setContentType(String type) {
this.contentType = type;
super.setContentType(type);
}
/**
* Wraps the underlying writer by a rewriter pipeline.
*
* @see javax.servlet.ServletResponseWrapper#getWriter()
*/
public PrintWriter getWriter() throws IOException {
if ( this.processor != null && this.writer == null ) {
return new PrintWriter(new Writer() {
@Override
public void close() throws IOException {
// nothing to do
}
@Override
public void flush() throws IOException {
// nothing to do
}
@Override
public void write(char[] cbuf, int off, int len)
throws IOException {
// nothing to do
}
});
}
if (writer == null) {
this.processor = this.getProcessor();
if ( this.processor != null ) {
this.writer = this.processor.getWriter();
}
if ( this.writer == null ) {
this.writer = super.getWriter();
}
}
return writer;
}
/**
* @see javax.servlet.ServletResponseWrapper#flushBuffer()
*/
public void flushBuffer() throws IOException {
if (writer != null) {
writer.flush();
} else {
super.flushBuffer();
}
}
/**
* Inform this response that the request processing is finished.
* @throws IOException
*/
public void finished(final boolean errorOccured) throws IOException {
if ( this.processor != null ) {
this.processor.finished(errorOccured);
this.processor = null;
}
}
/**
* If we have a pipeline configuration for the current request,
* we can adapt this response to a content handler.
* @see org.apache.sling.api.adapter.Adaptable#adaptTo(java.lang.Class)
*/
public <AdapterType> AdapterType adaptTo(Class<AdapterType> type) {
if ( type == ContentHandler.class ) {
this.processor = this.getProcessor();
if ( this.processor != null ) {
@SuppressWarnings("unchecked")
final AdapterType object = (AdapterType)this.processor.getContentHandler();
return object;
}
}
return super.adaptTo(type);
}
/**
* Search the first matching processor
*/
private Processor getProcessor() {
final ProcessingContext processorContext = new ServletProcessingContext(this.request, this, this.getSlingResponse(), this.contentType);
Processor found = null;
final List<ProcessorConfiguration> processorConfigs = this.processorManager.getProcessorConfigurations();
final Iterator<ProcessorConfiguration> i = processorConfigs.iterator();
while ( found == null && i.hasNext() ) {
final ProcessorConfiguration config = i.next();
if ( config.match(processorContext) ) {
try {
found = this.processorManager.getProcessor(config, processorContext);
this.request.getRequestProgressTracker().log("Found processor for post processing {0}", config);
} catch (final SlingException se) {
// if an exception occurs during setup of the pipeline and we are currently
// already processing an error, we ignore this!
if ( processorContext.getRequest().getAttribute("javax.servlet.error.status_code") != null ) {
this.request.getRequestProgressTracker().log("Ignoring found processor for post processing {0}" +
" as an error occured ({1}) during setup while processing another error.", config, se);
} else {
throw se;
}
}
}
}
return found;
}
}