/*
* Copyright (C) 2010. All rights reserved.
*/
package ro.isdc.wro.extensions.processor.css;
import java.io.IOException;
import java.io.Reader;
import java.io.Writer;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import ro.isdc.wro.WroRuntimeException;
import ro.isdc.wro.extensions.processor.support.ObjectPoolHelper;
import ro.isdc.wro.extensions.processor.support.sass.SassCss;
import ro.isdc.wro.model.resource.Resource;
import ro.isdc.wro.model.resource.ResourceType;
import ro.isdc.wro.model.resource.SupportedResourceType;
import ro.isdc.wro.model.resource.processor.Destroyable;
import ro.isdc.wro.model.resource.processor.ResourcePostProcessor;
import ro.isdc.wro.model.resource.processor.ResourcePreProcessor;
import ro.isdc.wro.util.ObjectFactory;
/**
* A processor using sass engine:
*
* @author Alex Objelean
* @created 27 Oct 2010
*/
@SupportedResourceType(ResourceType.CSS)
public class SassCssProcessor
implements ResourcePreProcessor, ResourcePostProcessor, Destroyable {
private static final Logger LOG = LoggerFactory.getLogger(SassCssProcessor.class);
public static final String ALIAS = "sassCss";
public static final String ALIAS_RUBY = "rubySassCss";
private ObjectPoolHelper<SassCss> enginePool;
/**
* default constructor that sets the engine used to RHINO for backwards compatibility.
*/
public SassCssProcessor() {
enginePool = new ObjectPoolHelper<SassCss>(new ObjectFactory<SassCss>() {
@Override
public SassCss create() {
return newEngine();
}
});
}
/**
* {@inheritDoc}
*/
@Override
public void process(final Resource resource, final Reader reader, final Writer writer)
throws IOException {
final String content = IOUtils.toString(reader);
final SassCss engine = enginePool.getObject();
try {
writer.write(engine.process(content));
} catch (final WroRuntimeException e) {
final String resourceUri = resource == null ? StringUtils.EMPTY : "[" + resource.getUri() + "]";
LOG.error("Exception while applying " + SassCss.class.getClass().getSimpleName() + " processor on the " + resourceUri
+ " resource, no processing applied...", e);
onException(e);
writer.write(content);
} finally {
reader.close();
writer.close();
try {
enginePool.returnObject(engine);
} catch (final Exception e) {
//should never happen
LOG.error("Cannot return lessCss engine to the pool", e);
}
}
}
/**
* Invoked when a processing exception occurs. By default the exception is thrown further.
*/
protected void onException(final WroRuntimeException e) {
throw e;
}
/**
* Method for processing with Rhino based engine
*
* @param content
* @return
*/
protected SassCss newEngine() {
return new SassCss();
}
/**
* {@inheritDoc}
*/
@Override
public void process(final Reader reader, final Writer writer)
throws IOException {
process(null, reader, writer);
}
@Override
public void destroy() throws Exception {
enginePool.destroy();
}
}