/**
* The MIT License (MIT)
*
* Copyright (c) 2014-2017 Yegor Bugayenko
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package org.takes.rs;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParserFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.sax.SAXSource;
import javax.xml.transform.stream.StreamResult;
import lombok.EqualsAndHashCode;
import lombok.ToString;
import org.takes.Response;
import org.w3c.dom.DocumentType;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
/**
* Response with properly indented XML body.
*
* <p>The class is immutable and thread-safe.
* @author Igor Khvostenkov (ikhvostenkov@gmail.com)
* @version $Id: 9729d963b0ae4108016c977d0072265c012fe3bf $
* @since 1.0
*/
@ToString(of = "origin")
@EqualsAndHashCode
public final class RsPrettyXml implements Response {
/**
* Xerces feature to disable external DTD validation.
*/
private static final String LOAD_EXTERNAL_DTD =
"http://apache.org/xml/features/nonvalidating/load-external-dtd";
/**
* Original response.
*/
private final Response origin;
/**
* Response with properly transformed body.
*/
private final List<Response> transformed;
/**
* Ctor.
* @param res Original response
*/
public RsPrettyXml(final Response res) {
this.transformed = new CopyOnWriteArrayList<Response>();
this.origin = res;
}
@Override
public Iterable<String> head() throws IOException {
return this.make().head();
}
@Override
public InputStream body() throws IOException {
return this.make().body();
}
/**
* Make a response.
* @return Response just made
* @throws IOException If fails
*/
@SuppressFBWarnings("JLM_JSR166_UTILCONCURRENT_MONITORENTER")
private Response make() throws IOException {
synchronized (this.transformed) {
if (this.transformed.isEmpty()) {
this.transformed.add(
new RsWithBody(
this.origin,
RsPrettyXml.transform(this.origin.body())
)
);
}
}
return this.transformed.get(0);
}
/**
* Format body with proper indents using SAX.
* @param body Response body
* @return New properly formatted body
* @throws IOException If fails
*/
private static byte[] transform(final InputStream body) throws IOException {
final SAXSource source = new SAXSource(new InputSource(body));
final ByteArrayOutputStream result = new ByteArrayOutputStream();
try {
final XMLReader xmlreader = SAXParserFactory.newInstance()
.newSAXParser().getXMLReader();
source.setXMLReader(xmlreader);
xmlreader.setFeature(
RsPrettyXml.LOAD_EXTERNAL_DTD, false
);
final String yes = "yes";
final Transformer transformer = TransformerFactory.newInstance()
.newTransformer();
// @checkstyle MultipleStringLiteralsCheck (2 line)
transformer.setOutputProperty(
OutputKeys.OMIT_XML_DECLARATION, yes
);
RsPrettyXml.prepareDocType(body, transformer);
transformer.setOutputProperty(OutputKeys.INDENT, yes);
transformer.transform(source, new StreamResult(result));
} catch (final TransformerException ex) {
throw new IOException(ex);
} catch (final SAXException ex) {
throw new IOException(ex);
} catch (final ParserConfigurationException ex) {
throw new IOException(ex);
}
return result.toByteArray();
}
/**
* Parses body to get DOCTYPE and configure Transformer
* with proper method, public id and system id.
* @param body The body to be parsed.
* @param transformer Transformer to configure with proper properties.
* @throws IOException if something goes wrong.
*/
private static void prepareDocType(final InputStream body,
final Transformer transformer) throws IOException {
try {
final String html = "html";
final DocumentType doctype = RsPrettyXml.getDocType(body);
if (null != doctype) {
if (null == doctype.getSystemId()
&& null == doctype.getPublicId()
// @checkstyle MultipleStringLiteralsCheck (3 line)
&& html.equalsIgnoreCase(doctype.getName())) {
transformer.setOutputProperty(OutputKeys.METHOD, html);
transformer.setOutputProperty(OutputKeys.VERSION, "5.0");
return;
}
if (null != doctype.getSystemId()) {
transformer.setOutputProperty(
OutputKeys.DOCTYPE_SYSTEM,
doctype.getSystemId()
);
}
if (null != doctype.getPublicId()) {
transformer.setOutputProperty(
OutputKeys.DOCTYPE_PUBLIC,
doctype.getPublicId()
);
}
}
} finally {
body.reset();
}
}
/**
* Parses the input stream and returns DocumentType built without loading
* any external DTD schemas.
* @param body The body to be parsed.
* @return The documents DocumentType.
* @throws IOException if something goes wrong.
*/
private static DocumentType getDocType(final InputStream body)
throws IOException {
final DocumentBuilderFactory factory =
DocumentBuilderFactory.newInstance();
try {
factory.setFeature(RsPrettyXml.LOAD_EXTERNAL_DTD, false);
final DocumentBuilder builder = factory.newDocumentBuilder();
return builder.parse(body).getDoctype();
} catch (final ParserConfigurationException ex) {
throw new IOException(ex);
} catch (final SAXException ex) {
throw new IOException(ex);
}
}
}