/*
* (C) Copyright 2006-2008 Nuxeo SAS (http://nuxeo.com/) and contributors.
*
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the GNU Lesser General Public License
* (LGPL) version 2.1 which accompanies this distribution, and is available at
* http://www.gnu.org/licenses/lgpl.html
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* Contributors:
* bstefanescu
*
* $Id$
*/
package org.nuxeo.ecm.webengine.scripting;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.io.Reader;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import javax.script.Compilable;
import javax.script.CompiledScript;
import javax.script.ScriptContext;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import javax.script.SimpleBindings;
import javax.script.SimpleScriptContext;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.nuxeo.ecm.webengine.loader.WebLoader;
/**
* @author <a href="mailto:bs@nuxeo.com">Bogdan Stefanescu</a>
*
*/
public class Scripting {
private static final Log log = LogFactory.getLog(Scripting.class);
private final ConcurrentMap<File, Entry> cache = new ConcurrentHashMap<File, Entry>();
// this will be lazy initialized
private ScriptEngineManager scriptMgr;
private final WebLoader loader;
public Scripting(WebLoader loader) {
this.loader = loader;
}
public static CompiledScript compileScript(ScriptEngine engine, File file) throws ScriptException {
if (engine instanceof Compilable) {
Compilable comp = (Compilable)engine;
try {
Reader reader = new FileReader(file);
try {
return comp.compile(reader);
} finally {
reader.close();
}
} catch (IOException e) {
throw new ScriptException(e);
}
} else {
return null;
}
}
/**
* Lazy init scripting manager to avoid loading script engines when
* no scripting is used.
* <p>
* Javax Scripting is not used by default in WebWengine,
* we are using directly the Groovy engine.
* This also fixes an annoying pb on Mac in java5 due to AppleScripting
* which is failing to register.
*
* @return the scriptMgr
*/
public ScriptEngineManager getEngineManager() {
if (scriptMgr == null) {
scriptMgr = new ScriptEngineManager();
}
return scriptMgr;
}
public boolean isScript(String ext) {
return getEngineManager().getEngineByExtension(ext) != null;
}
public Object runScript(ScriptFile script) throws Exception {
return runScript(script, null);
}
public Object runScript(ScriptFile script, Map<String, Object> args) throws Exception {
if (log.isDebugEnabled()) {
log.debug("## Running Script: "+script.getFile());
}
if ("groovy".equals(script.getExtension())) {
return loader.getGroovyScripting().eval(script.file, args);
} else {
return _runScript(script, args);
}
}
//TODO: add an output stream to use as arg?
protected Object _runScript(ScriptFile script, Map<String, Object> args) throws Exception {
SimpleBindings bindings = new SimpleBindings();
if (args != null) {
bindings.putAll(args);
}
String ext = script.getExtension();
// check for a script engine
ScriptEngine engine = getEngineManager().getEngineByExtension(ext);
if (engine != null) {
ScriptContext ctx = new SimpleScriptContext();
ctx.setBindings(bindings, ScriptContext.ENGINE_SCOPE);
CompiledScript comp = getCompiledScript(engine, script.getFile()); // use cache for compiled scripts
if (comp != null) {
return comp.eval(ctx);
} // compilation not supported - eval it on the fly
try {
Reader reader = new FileReader(script.getFile());
try { // TODO use __result__ to pass return value for engine that doesn't returns like jython
Object result = engine.eval(reader, ctx);
if (result == null) {
result = bindings.get("__result__");
}
return result;
} finally {
reader.close();
}
} catch (IOException e) {
throw new ScriptException(e);
}
}
return null;
}
//TODO move this in a python scripting adapter
// @SuppressWarnings("unchecked")
// public static Map convertPythonMap(PyDictionary dict) {
// PyList list = dict.items();
// Map<String, PyObject> table = new HashMap();
// for(int i = list.__len__(); i-- > 0; ) {
// PyTuple tup = (PyTuple) list.__getitem__(i);
// String key = tup.__getitem__(0).toString();
// table.put(key, tup.__getitem__(1));
// }
// return table;
// }
public CompiledScript getCompiledScript(ScriptEngine engine, File file) throws ScriptException {
Entry entry = cache.get(file);
long tm = file.lastModified();
if (entry != null) {
if (entry.lastModified < tm) { // recompile
entry.script = compileScript(engine, file);
entry.lastModified = tm;
}
return entry.script;
}
CompiledScript script = compileScript(engine, file);
if (script != null) {
cache.putIfAbsent(file, new Entry(script, tm));
return script;
}
return null;
}
class Entry {
public CompiledScript script;
public long lastModified;
Entry(CompiledScript script, long lastModified) {
this.lastModified = lastModified;
this.script = script;
}
}
}