/*
* Copyright 2011-2012 the original author or authors.
*
* 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.jetdrone.vertx.yoke.engine;
import com.jetdrone.vertx.yoke.core.YokeAsyncResult;
import org.mvel2.templates.CompiledTemplate;
import org.mvel2.templates.TemplateCompiler;
import org.mvel2.templates.TemplateRuntime;
import org.vertx.java.core.AsyncResult;
import org.vertx.java.core.AsyncResultHandler;
import org.vertx.java.core.Handler;
import org.vertx.java.core.buffer.Buffer;
import java.io.IOException;
import java.util.Map;
public class MVELEngine extends AbstractEngine<CompiledTemplate> {
private final String prefix;
public MVELEngine(final String views) {
if ("".equals(views)) {
prefix = views;
} else {
prefix = views.endsWith("/") ? views : views + "/";
}
}
@Override
public void render(final String filename, final Map<String, Object> context, final Handler<AsyncResult<Buffer>> next) {
read(prefix + filename, new AsyncResultHandler<String>() {
@Override
public void handle(AsyncResult<String> asyncResult) {
if (asyncResult.failed()) {
next.handle(new YokeAsyncResult<Buffer>(asyncResult.cause()));
} else {
try {
CompiledTemplate template = compile(prefix + filename, asyncResult.result());
next.handle(new YokeAsyncResult<>(new Buffer((String) TemplateRuntime.execute(template, context))));
} catch (IOException ex) {
next.handle(new YokeAsyncResult<Buffer>(ex));
}
}
}
});
}
private CompiledTemplate compile(String filename, String templateText) throws IOException {
CompiledTemplate template = getTemplateFromCache(filename);
if (template == null) {
// real compile
template = TemplateCompiler.compileTemplate(templateText);
putTemplateToCache(filename, template);
}
return template;
}
}