/*
* Copyright 2016 predic8 GmbH, www.predic8.com
* 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.predic8.membrane.core.lang.javascript;
import com.google.common.base.Function;
import com.predic8.membrane.core.Router;
import com.predic8.membrane.core.lang.LanguageSupport;
import com.predic8.membrane.core.lang.ScriptExecutorPool;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import java.util.Map;
public class JavascriptLanguageSupport extends LanguageSupport {
private static final Logger log = LoggerFactory.getLogger(JavascriptLanguageSupport.class);
private abstract class JavascriptScriptExecutorPool<R> extends ScriptExecutorPool<ScriptEngine,R>{
private final String javascriptCode;
ScriptEngineManager sce;
final static String javascriptEngineName = "nashorn";
private JavascriptScriptExecutorPool(Router router, String expression) {
this.javascriptCode = expression;
sce = new ScriptEngineManager();
init(router);
}
@Override
protected Object invoke(ScriptEngine script, Map<String, Object> parameters) {
for(String name : parameters.keySet())
script.put(name,parameters.get(name));
try {
return script.eval(javascriptCode);
} catch (ScriptException e) {
log.error("Error compiling script:", e);
throw new RuntimeException("Error compiling script:", e);
}
}
@Override
protected ScriptEngine createOneScript() {
synchronized (sce){
return sce.getEngineByName(javascriptEngineName);
}
}
}
@Override
public Function<Map<String, Object>, Boolean> compileExpression(Router router, String src) {
return new JavascriptScriptExecutorPool<Boolean>(router, getScriptWithImports(src)) {
@Override
public Boolean apply(Map<String, Object> parameters) {
Object result = this.execute(parameters);
if (result instanceof Boolean)
return (Boolean)result;
return false;
}
};
}
@Override
public Function<Map<String, Object>, Object> compileScript(Router router, String script) {
return new JavascriptScriptExecutorPool<Object>(router, getScriptWithImports(script)) {
@Override
public Object apply(Map<String, Object> parameters) {
return this.execute(parameters);
}
};
}
private String getScriptWithImports(String src) {
return "var imports = new JavaImporter(com.predic8.membrane.core.interceptor.Outcome," +
"com.predic8.membrane.core.http" +
")\n" +
"with(imports){\n" +
src +
"\n}";
}
}