/**
* 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.camel.processor.validation;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.StringWriter;
import java.net.URL;
import java.util.Collections;
import javax.xml.XMLConstants;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.dom.DOMResult;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.sax.SAXResult;
import javax.xml.transform.sax.SAXSource;
import javax.xml.transform.stax.StAXSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import javax.xml.validation.Schema;
import javax.xml.validation.SchemaFactory;
import javax.xml.validation.Validator;
import org.w3c.dom.Node;
import org.w3c.dom.ls.LSResourceResolver;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.apache.camel.AsyncCallback;
import org.apache.camel.AsyncProcessor;
import org.apache.camel.Exchange;
import org.apache.camel.ExpectedBodyTypeException;
import org.apache.camel.RuntimeTransformException;
import org.apache.camel.TypeConverter;
import org.apache.camel.converter.jaxp.XmlConverter;
import org.apache.camel.util.AsyncProcessorHelper;
import org.apache.camel.util.IOHelper;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* A processor which validates the XML version of the inbound message body
* against some schema either in XSD or RelaxNG
*/
public class ValidatingProcessor implements AsyncProcessor {
private static final Logger LOG = LoggerFactory.getLogger(ValidatingProcessor.class);
private XmlConverter converter = new XmlConverter();
private String schemaLanguage = XMLConstants.W3C_XML_SCHEMA_NS_URI;
private Schema schema;
private Source schemaSource;
private SchemaFactory schemaFactory;
private URL schemaUrl;
private File schemaFile;
private byte[] schemaAsByteArray;
private ValidatorErrorHandler errorHandler = new DefaultValidationErrorHandler();
private boolean useDom;
private boolean useSharedSchema = true;
private LSResourceResolver resourceResolver;
private boolean failOnNullBody = true;
private boolean failOnNullHeader = true;
private String headerName;
public void process(Exchange exchange) throws Exception {
AsyncProcessorHelper.process(this, exchange);
}
public boolean process(Exchange exchange, AsyncCallback callback) {
try {
doProcess(exchange);
} catch (Exception e) {
exchange.setException(e);
}
callback.done(true);
return true;
}
protected void doProcess(Exchange exchange) throws Exception {
Schema schema;
if (isUseSharedSchema()) {
schema = getSchema();
} else {
schema = createSchema();
}
Validator validator = schema.newValidator();
// the underlying input stream, which we need to close to avoid locking files or other resources
Source source = null;
InputStream is = null;
try {
Result result = null;
// only convert to input stream if really needed
if (isInputStreamNeeded(exchange)) {
is = getContentToValidate(exchange, InputStream.class);
if (is != null) {
source = getSource(exchange, is);
}
} else {
Object content = getContentToValidate(exchange);
if (content != null) {
source = getSource(exchange, content);
}
}
if (shouldUseHeader()) {
if (source == null && isFailOnNullHeader()) {
throw new NoXmlHeaderValidationException(exchange, headerName);
}
} else {
if (source == null && isFailOnNullBody()) {
throw new NoXmlBodyValidationException(exchange);
}
}
//CAMEL-7036 We don't need to set the result if the source is an instance of StreamSource
if (source instanceof DOMSource) {
result = new DOMResult();
} else if (source instanceof SAXSource) {
result = new SAXResult();
} else if (source instanceof StAXSource || source instanceof StreamSource) {
result = null;
}
if (source != null) {
// create a new errorHandler and set it on the validator
// must be a local instance to avoid problems with concurrency (to be
// thread safe)
ValidatorErrorHandler handler = errorHandler.getClass().newInstance();
validator.setErrorHandler(handler);
try {
LOG.trace("Validating {}", source);
validator.validate(source, result);
handler.handleErrors(exchange, schema, result);
} catch (SAXParseException e) {
// can be thrown for non well formed XML
throw new SchemaValidationException(exchange, schema, Collections.singletonList(e),
Collections.<SAXParseException>emptyList(),
Collections.<SAXParseException>emptyList());
}
}
} finally {
IOHelper.close(is);
}
}
private Object getContentToValidate(Exchange exchange) {
if (shouldUseHeader()) {
return exchange.getIn().getHeader(headerName);
} else {
return exchange.getIn().getBody();
}
}
private <T> T getContentToValidate(Exchange exchange, Class<T> clazz) {
if (shouldUseHeader()) {
return exchange.getIn().getHeader(headerName, clazz);
} else {
return exchange.getIn().getBody(clazz);
}
}
private boolean shouldUseHeader() {
return headerName != null;
}
public void loadSchema() throws Exception {
// force loading of schema
schema = createSchema();
}
// Properties
// -----------------------------------------------------------------------
public Schema getSchema() throws IOException, SAXException {
if (schema == null) {
schema = createSchema();
}
return schema;
}
public void setSchema(Schema schema) {
this.schema = schema;
}
public String getSchemaLanguage() {
return schemaLanguage;
}
public void setSchemaLanguage(String schemaLanguage) {
this.schemaLanguage = schemaLanguage;
}
public Source getSchemaSource() throws IOException {
if (schemaSource == null) {
schemaSource = createSchemaSource();
}
return schemaSource;
}
public void setSchemaSource(Source schemaSource) {
this.schemaSource = schemaSource;
}
public URL getSchemaUrl() {
return schemaUrl;
}
public void setSchemaUrl(URL schemaUrl) {
this.schemaUrl = schemaUrl;
}
public File getSchemaFile() {
return schemaFile;
}
public void setSchemaFile(File schemaFile) {
this.schemaFile = schemaFile;
}
public byte[] getSchemaAsByteArray() {
return schemaAsByteArray;
}
public void setSchemaAsByteArray(byte[] schemaAsByteArray) {
this.schemaAsByteArray = schemaAsByteArray;
}
public SchemaFactory getSchemaFactory() {
if (schemaFactory == null) {
schemaFactory = createSchemaFactory();
}
return schemaFactory;
}
public void setSchemaFactory(SchemaFactory schemaFactory) {
this.schemaFactory = schemaFactory;
}
public ValidatorErrorHandler getErrorHandler() {
return errorHandler;
}
public void setErrorHandler(ValidatorErrorHandler errorHandler) {
this.errorHandler = errorHandler;
}
@Deprecated
public boolean isUseDom() {
return useDom;
}
/**
* Sets whether DOMSource and DOMResult should be used.
*
* @param useDom true to use DOM otherwise
*/
@Deprecated
public void setUseDom(boolean useDom) {
this.useDom = useDom;
}
public boolean isUseSharedSchema() {
return useSharedSchema;
}
public void setUseSharedSchema(boolean useSharedSchema) {
this.useSharedSchema = useSharedSchema;
}
public LSResourceResolver getResourceResolver() {
return resourceResolver;
}
public void setResourceResolver(LSResourceResolver resourceResolver) {
this.resourceResolver = resourceResolver;
}
public boolean isFailOnNullBody() {
return failOnNullBody;
}
public void setFailOnNullBody(boolean failOnNullBody) {
this.failOnNullBody = failOnNullBody;
}
public boolean isFailOnNullHeader() {
return failOnNullHeader;
}
public void setFailOnNullHeader(boolean failOnNullHeader) {
this.failOnNullHeader = failOnNullHeader;
}
public String getHeaderName() {
return headerName;
}
public void setHeaderName(String headerName) {
this.headerName = headerName;
}
// Implementation methods
// -----------------------------------------------------------------------
protected SchemaFactory createSchemaFactory() {
SchemaFactory factory = SchemaFactory.newInstance(schemaLanguage);
if (getResourceResolver() != null) {
factory.setResourceResolver(getResourceResolver());
}
return factory;
}
protected Source createSchemaSource() throws IOException {
throw new IllegalArgumentException("You must specify either a schema, schemaFile, schemaSource or schemaUrl property");
}
protected Schema createSchema() throws SAXException, IOException {
SchemaFactory factory = getSchemaFactory();
URL url = getSchemaUrl();
if (url != null) {
return factory.newSchema(url);
}
File file = getSchemaFile();
if (file != null) {
return factory.newSchema(file);
}
byte[] bytes = getSchemaAsByteArray();
if (bytes != null) {
return factory.newSchema(new StreamSource(new ByteArrayInputStream(schemaAsByteArray)));
}
Source source = getSchemaSource();
return factory.newSchema(source);
}
/**
* Checks whether we need an {@link InputStream} to access the message body or header.
* <p/>
* Depending on the content in the message body or header, we may not need to convert
* to {@link InputStream}.
*
* @param exchange the current exchange
* @return <tt>true</tt> to convert to {@link InputStream} beforehand converting to {@link Source} afterwards.
*/
protected boolean isInputStreamNeeded(Exchange exchange) {
Object content = getContentToValidate(exchange);
if (content == null) {
return false;
}
if (content instanceof InputStream) {
return true;
} else if (content instanceof Source) {
return false;
} else if (content instanceof String) {
return false;
} else if (content instanceof byte[]) {
return false;
} else if (content instanceof Node) {
return false;
} else if (exchange.getContext().getTypeConverterRegistry().lookup(Source.class, content.getClass()) != null) {
//there is a direct and hopefully optimized converter to Source
return false;
}
// yes an input stream is needed
return true;
}
/**
* Converts the inbound body or header to a {@link Source}, if it is <b>not</b> already a {@link Source}.
* <p/>
* This implementation will prefer to source in the following order:
* <ul>
* <li>DOM - DOM if explicit configured to use DOM</li>
* <li>SAX - SAX as 2nd choice</li>
* <li>Stream - Stream as 3rd choice</li>
* <li>DOM - DOM as 4th choice</li>
* </ul>
*/
protected Source getSource(Exchange exchange, Object content) {
if (isUseDom()) {
// force DOM
return exchange.getContext().getTypeConverter().tryConvertTo(DOMSource.class, exchange, content);
}
// body or header may already be a source
if (content instanceof Source) {
return (Source) content;
}
Source source = null;
if (content instanceof InputStream) {
return new StreamSource((InputStream) content);
}
if (content != null) {
TypeConverter tc = exchange.getContext().getTypeConverterRegistry().lookup(Source.class, content.getClass());
if (tc != null) {
source = tc.convertTo(Source.class, exchange, content);
}
}
if (source == null) {
// then try SAX
source = exchange.getContext().getTypeConverter().tryConvertTo(SAXSource.class, exchange, content);
}
if (source == null) {
// then try stream
source = exchange.getContext().getTypeConverter().tryConvertTo(StreamSource.class, exchange, content);
}
if (source == null) {
// and fallback to DOM
source = exchange.getContext().getTypeConverter().tryConvertTo(DOMSource.class, exchange, content);
}
if (source == null) {
if (isFailOnNullBody()) {
throw new ExpectedBodyTypeException(exchange, Source.class);
} else {
try {
source = converter.toDOMSource(converter.createDocument());
} catch (ParserConfigurationException e) {
throw new RuntimeTransformException(e);
}
}
}
return source;
}
}