handle sass files through wro4j

src/main/java/com/commafeed/frontend/resources/SassImportProcessor.java

@@ -0,0 +1,27 @@
+package com.commafeed.frontend.resources;
+
+import java.io.IOException;
+import java.util.List;
+
+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.impl.css.CssImportPreProcessor;
+
+@SupportedResourceType(ResourceType.CSS)
+public class SassImportProcessor extends CssImportPreProcessor {
+
+	@Override
+	protected String doTransform(String cssContent, List<Resource> foundImports)
+			throws IOException {
+		for (Resource resource : foundImports) {
+			String uri = resource.getUri();
+			int lastSlash = uri.lastIndexOf('/');
+			String prefix = uri.substring(0, lastSlash);
+			String suffix = uri.substring(lastSlash + 1);
+			uri = prefix + "/_" + suffix + ".scss";
+			resource.setUri(uri);
+		}
+		return super.doTransform(cssContent, foundImports);
+	}
+}

src/main/java/com/commafeed/frontend/resources/WroManagerFactory.java

@@ -10,6 +10,7 @@ public class WroManagerFactory extends ConfigurableWroManagerFactory {
 	@Override
 	protected void contributePreProcessors(Map<String, ResourcePreProcessor> map) {
 		map.put("sassOnlyProcessor", new SassOnlyProcessor());
+		map.put("sassImport", new SassImportProcessor());
 	}
 
 }

src/main/webapp/WEB-INF/wro.properties

@@ -10,7 +10,7 @@ jmxEnabled=false
 managerFactoryClassName=com.commafeed.frontend.resources.WroManagerFactory
 
 #List of preProcessors
-preProcessors=cssUrlRewriting,semicolonAppender,googleClosureSimple,sassOnlyProcessor,cssMin
+preProcessors=cssUrlRewriting,sassImport,semicolonAppender,googleClosureSimple,sassOnlyProcessor,cssMin
 #List of postProcessors
 postProcessors=
 

src/main/webapp/WEB-INF/wro.xml

@@ -23,7 +23,7 @@
 	</group>
 
 	<group name="app">
-		<css>/css/*.css</css>
+		<css>/sass/app.scss</css>
 		<js>/js/*.js</js>
 	</group>