/*
* Copyright 2013, The Sporting Exchange Limited
*
* 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 com.betfair.cougar.codegen;
import javax.xml.XMLConstants;
import javax.xml.transform.dom.DOMSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import org.w3c.dom.Document;
import com.betfair.cougar.codegen.except.PluginException;
import com.betfair.cougar.codegen.resolver.InterceptingResolver;
/**
* Does schema validation of XML documents (replacing xml-maven-plugin, which can't handle
* include files).
* <p>
* <h2>A note on catalogs</h2>
* <p>
* We realised (the hard way) that because Interface.xsd (which drives service definition validation)
* references the w3.org xml spec (for xi:include support), our build server was constantly hitting
* www.w3.org, and when we started getting timeouts to that server, our builds starting failing.
* <p>
* This validator now uses a {@link org.apache.xerces.util.XMLCatalogResolver} so we can retrieve schemas locally.
* See http://xml.apache.org/commons/components/resolver/resolver-article.html.
*/
public class XmlValidator {
private final InterceptingResolver resolver;
public XmlValidator(InterceptingResolver resolver) {
this.resolver = resolver;
}
/**
* Validate the given xmlDocument, using any schemas specified in the document itself.
*
* @throws PluginException for any validation or IO errors.
*/
public void validate(Document doc) {
try {
doValidate(doc);
}
catch (Exception e) {
throw new PluginException("Error validating document: " + e, e);
}
}
private void doValidate(Document doc) throws Exception {
// preparsed schema seems to be the only way to get xi:include working,
// see http://www.xml.com/lpt/a/1597
DOMSource source = new DOMSource(doc);
SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
Schema schema = factory.newSchema();
javax.xml.validation.Validator validator = schema.newValidator();
// see notes in javadoc above
validator.setResourceResolver(resolver);
validator.validate(source);
}
}