/java/src/org/jpublish/action/ScriptAction.java

/*

 * Copyright 2004-2007 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 org.jpublish.action;



import com.anthonyeden.lib.config.Configuration;

import com.atlassian.util.profiling.UtilTimerStack;

import org.apache.bsf.BSFManager;

import org.apache.bsf.util.IOUtils;

import org.apache.commons.logging.Log;

import org.apache.commons.logging.LogFactory;

import org.jpublish.JPublishContext;

import org.jpublish.Page;

import org.jpublish.SiteContext;



import javax.servlet.ServletContext;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import java.io.File;

import java.io.FileReader;



/**

 * An action which is implemented in a BSF supported scripting language.

 * Script actions have access to several varibles:

 * <p/>

 * <p>These are always available:</p>

 * <p/>

 * <p/>

 * <b>site</b> - The SiteContext<br>

 * <b>syslog</b> - Standard logging stream (Log4J Category)<br>

 * </p>

 * <p/>

 * <p>If there is a context defined when the action is executed (all

 * actions excluding startup actions):</p>

 * <p/>

 * <p/>

 * <b>context</b> - The current context<br>

 * <b>application</b> - The ServletContext<br>

 * <b>request</b> - The HTTP request<br>

 * <b>response</b> - The HTTP response<br>

 * <b>session</b> - The HTTP session<br>

 * <b>page</b> - The Page object<br>

 * </p>

 * <p/>

 * <p>If the action is executed with a configuration object then that object

 * will be included as <code>configuration</code>.</p>

 *

 * @author Anthony Eden

 * @author David Jones

 */



public class ScriptAction implements Action {



    private static Log log = LogFactory.getLog(ScriptAction.class);



    private SiteContext siteContext;

    private File script;

    private String scriptLang = null;

    private long timeLastLoaded = 0;

    private String scriptString = null;



    /**

     * Construct a new ScriptAction for the given script.  The path to the

     * script should be an absolute path.

     *

     * @param siteContext The SiteContext

     * @param script      The path to the script

     */



    public ScriptAction(SiteContext siteContext, String script) {

        this(siteContext, new File(script));

    }



    /**

     * Construct a new ScriptAction for the given script.

     *

     * @param siteContext The SiteContext

     * @param script      The file representing the script

     */



    public ScriptAction(SiteContext siteContext, File script) {

        this.siteContext = siteContext;

        this.script = script;

        if (log.isDebugEnabled())

            log.debug("Creating new ScriptAction for " + script.getName());

    }



    /**

     * Execute the action script represented by this ScriptAction.

     *

     * @param context       The current context

     * @param configuration The configuration object

     * @throws Exception

     */



    public void execute(JPublishContext context, Configuration configuration) throws Exception {

        if (log.isDebugEnabled())

            log.debug("Executing script: " + script);



        BSFManager bsfManager = new BSFManager();



        // expose standard items in the context

        if (context != null) {

            ServletContext application = (ServletContext) context.get("application");

            HttpServletRequest request = (HttpServletRequest) context.get("request");

            HttpServletResponse response = (HttpServletResponse) context.get("response");

            HttpSession session = (HttpSession) context.get("session");

            Page page = (Page) context.get("page");



            // expose the context

            bsfManager.declareBean("context", context, JPublishContext.class);



            // expose the context.  This variable has been removed as of JP2.

            //bsfManager.declareBean("vc", context, JPublishContext.class);



            // expose the page object.

            if (page == null) {

                if (log.isDebugEnabled())

                    log.debug("Page request is null");

            } else {

                bsfManager.declareBean("page", page, Page.class);

            }



            // expose standard HttpServlet objects

            if (request == null) {

                if (log.isDebugEnabled())

                    log.debug("HTTP request is null");

            } else {

                bsfManager.declareBean("request", request, HttpServletRequest.class);

            }



            if (response == null) {

                if (log.isDebugEnabled())

                    log.debug("HTTP response is null");

            } else {

                bsfManager.declareBean("response", response, HttpServletResponse.class);

            }



            if (session == null) {

                if (log.isDebugEnabled())

                    log.debug("HTTP session is null");

            } else {

                bsfManager.declareBean("session", session, HttpSession.class);

            }



            if (application == null) {

                if (log.isDebugEnabled())

                    log.debug("ServletContext is null");

            } else {

                bsfManager.declareBean("application", application, ServletContext.class);

            }

        }



        // these objects are exposed regardless if there is a context

        // object or not.  In other words they are accesible to startup

        // actions

        bsfManager.declareBean("syslog", SiteContext.syslog, Log.class);



        if (siteContext == null) {

            if (log.isDebugEnabled())

                log.debug("SiteContext is null");

        } else {

            bsfManager.declareBean("site", siteContext, SiteContext.class);

        }



        if (configuration == null) {

            if (log.isDebugEnabled())

                log.debug("Configuration is null");

        } else {

            bsfManager.declareBean("configuration", configuration, Configuration.class);

        }



        // The following code was added by David Jones.  This will have

        // to be rewritten to use an ActionContent object for getting the

        // last modified time once I get to writing it. -AE

        if (scriptLang == null) {

            scriptLang = BSFManager.getLangFromFilename(script.getName());

        }



        boolean reloadScript = false;

        long scriptLastModified = script.lastModified();

        if (scriptLastModified > timeLastLoaded) {

            if (log.isDebugEnabled())

                log.debug("Loading updated or new script: " + script.getName());

            reloadScript = true;

        }



        if (reloadScript || scriptString == null) {

            synchronized (this) {

                if (reloadScript || scriptString == null) {

                    timeLastLoaded = System.currentTimeMillis();

                    scriptString = IOUtils.getStringFromReader(new FileReader(script));

                }

            }

        }

        try {

            UtilTimerStack.push(script.getName());

            bsfManager.exec(scriptLang, script.getCanonicalPath(), 0, 0, scriptString);

        } finally {

            UtilTimerStack.pop(script.getName());

        }

    }

}