1 files changed, 304 insertions, 0 deletions
diff --git a/sandbox/sebastien/java/sca-node/distribution/webapp/src/main/java/org/apache/tuscany/sca/webapp/WarContextListener.java b/sandbox/sebastien/java/sca-node/distribution/webapp/src/main/java/org/apache/tuscany/sca/webapp/WarContextListener.java
new file mode 100644
index 0000000000..e46cadfa3d
--- /dev/null
+++ b/sandbox/sebastien/java/sca-node/distribution/webapp/src/main/java/org/apache/tuscany/sca/webapp/WarContextListener.java
@@ -0,0 +1,304 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.apache.tuscany.sca.webapp;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.net.MalformedURLException;
+import java.net.URISyntaxException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
+import java.util.List;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import javax.servlet.ServletContext;
+import javax.servlet.ServletContextEvent;
+import javax.servlet.ServletContextListener;
+
+import org.apache.tuscany.sca.domain.SCADomain;
+import org.apache.tuscany.sca.node.NodeException;
+import org.apache.tuscany.sca.node.SCANode;
+import org.apache.tuscany.sca.node.SCANodeFactory;
+
+/**
+ * A ServletContextListener for the Tuscany WAR distribution.
+ * 
+ * Starts and stops a Tuscany SCA domain Node for the webapp. 
+ */
+public class WarContextListener implements ServletContextListener {
+    private final static Logger logger = Logger.getLogger(WarContextListener.class.getName());
+
+    protected SCANode node;
+    protected SCADomain domain;
+    protected AddableURLClassLoader classLoader;
+    protected File repository;
+
+    protected boolean useHotUpdate;
+    protected long hotDeployInterval = 2000; // 2 seconds, 0 = no hot deploy
+    protected Thread hotDeployThread;
+    protected boolean stopHotDeployThread;
+
+    protected HashMap<URL, Long> existingContributions; // value is last modified time
+
+    private String domainName;
+    private String nodeName;
+
+    protected static final String NODE_ATTRIBUTE = WarContextListener.class.getName() + ".TuscanyNode";
+    protected static final String REPOSITORY_FOLDER_NAME = "sca-contributions";
+
+    public void contextInitialized(ServletContextEvent event) {
+        ServletContext servletContext = event.getServletContext();
+        initParameters(servletContext);
+        try {
+
+            initNode();
+        
+        } catch (Throwable e) {
+            e.printStackTrace();
+            servletContext.log("exception initializing SCA node", e);
+        }
+    }
+
+    public void contextDestroyed(ServletContextEvent event) {
+        if (node != null) {
+            stopNode();
+        }
+    }
+
+    protected void stopNode() {
+        try {
+
+            node.stop();
+            logger.log(Level.INFO, "SCA node stopped");
+
+        } catch (Throwable e) {
+            e.printStackTrace();
+            logger.log(Level.SEVERE, "exception stopping SCA Node", e);
+        }
+    }
+
+    protected void initNode() throws NodeException, URISyntaxException {
+        logger.log(Level.INFO, "SCA node starting");
+        
+        classLoader = new AddableURLClassLoader(new URL[] {}, Thread.currentThread().getContextClassLoader());
+        Thread.currentThread().setContextClassLoader(classLoader);
+        
+        SCANodeFactory nodeFactory = SCANodeFactory.newInstance();
+        node = nodeFactory.createSCANode(nodeName, domainName);
+        domain = node.getDomain();
+
+        existingContributions = new HashMap<URL, Long>();
+        URL[] contributions = getContributionJarURLs(repository);
+        for (URL contribution : contributions) {
+                addContribution(contribution);
+        }
+        
+        node.start();
+
+        initHotDeploy(repository);
+    }
+
+    protected void addContribution(URL contribution) throws URISyntaxException, NodeException {
+        classLoader.addURL(contribution);
+        node.addContribution(contribution.toString(), contribution);
+        existingContributions.put(contribution, new Long(new File(contribution.toURI()).lastModified()));
+        logger.log(Level.INFO, "Added contribution: " + contribution);
+    }
+
+    protected URL[] getContributionJarURLs(File repositoryDir) {
+
+        String[] jarNames = repositoryDir.list(new FilenameFilter() {
+            public boolean accept(File dir, String name) {
+                return name.endsWith(".jar");
+            }});
+
+        List<URL> contributionJars = new ArrayList<URL>();
+        if (jarNames != null) {
+            for (String jar : jarNames) {
+                try {
+                    contributionJars.add(new File(repositoryDir, jar).toURL());
+                } catch (MalformedURLException e) {
+                    throw new RuntimeException(e);
+                }
+            }
+        }
+
+        return contributionJars.toArray(new URL[contributionJars.size()]);
+    }
+
+    private void initHotDeploy(final File repository) {
+
+        if (hotDeployInterval == 0) {
+            return; // hotUpdateInterval of 0 disables hotupdate
+        }
+
+        Runnable runable = new Runnable() {
+
+            public void run() {
+                logger.info("Contribution hot deploy activated");
+                while (!stopHotDeployThread) {
+                    try {
+                        Thread.sleep(hotDeployInterval);
+                    } catch (InterruptedException e) {
+                    }
+                    if (!stopHotDeployThread) {
+                        checkForUpdates(repository);
+                    }
+                }
+                logger.info("Tuscany contribution hot deploy stopped");
+            }
+        };
+        hotDeployThread = new Thread(runable, "TuscanyHotDeploy");
+        stopHotDeployThread = false;
+        hotDeployThread.start();
+    }
+
+    protected void checkForUpdates(File repository) {
+        URL[] currentContributions = getContributionJarURLs(repository);
+
+        List<URL> addedContributions = getAddedContributions(currentContributions);
+        for (URL contribution : addedContributions) {
+            try {
+                addContribution(contribution);
+  //              node.startContribution(contribution.toString());
+            } catch (Throwable e) {
+                e.printStackTrace();
+                logger.log(Level.WARNING, "Exception adding contribution: " + e);
+            }
+        }
+        if (addedContributions.size() > 0) {
+            try {
+                node.start();
+            } catch (NodeException e) {
+                e.printStackTrace();
+                logger.log(Level.WARNING, "Exception restarting node for added contributions: " + e);
+            }
+        }
+        
+        if (useHotUpdate && areContributionsAltered(currentContributions)) {
+            stopNode();
+            try {
+                initNode();
+            } catch (Throwable e) {
+                e.printStackTrace();
+                logger.log(Level.SEVERE, "exception starting SCA Node", e);
+            }
+        }
+    }
+
+    protected List<URL> getAddedContributions(URL[] currentContrabutions) {
+        List<URL> urls = new ArrayList<URL>();
+        for (URL url : currentContrabutions) {
+            if (!existingContributions.containsKey(url)) {
+                urls.add(url);
+            }
+        }
+        return urls;
+    }
+
+    protected boolean areContributionsAltered(URL[] currentContrabutions) {
+        try {
+            
+            List removedContributions = getRemovedContributions(currentContrabutions);
+            List updatedContributions = getUpdatedContributions(currentContrabutions);
+            
+            return (removedContributions.size() > 0 || updatedContributions.size() > 0);
+
+        } catch (URISyntaxException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    protected List<URL> getUpdatedContributions(URL[] currentContrabutions) throws URISyntaxException {
+        List<URL> urls = new ArrayList<URL>();
+        for (URL url : currentContrabutions) {
+            if (existingContributions.containsKey(url)) {
+                File curentFile = new File(url.toURI());
+                if (curentFile.lastModified() != existingContributions.get(url)) {
+                    urls.add(url);
+                    logger.info("updated contribution: " + curentFile.getName());
+                }
+            }
+        }
+        return urls;
+    }
+
+    protected List getRemovedContributions(URL[] currentContrabutions) throws URISyntaxException {
+        List<URL> currentUrls = Arrays.asList(currentContrabutions);
+        List<URL> urls = new ArrayList<URL>();
+        for (URL url : existingContributions.keySet()) {
+            if (!currentUrls.contains(url)) {
+                urls.add(url);
+            }
+        }
+        for (URL url : urls) {
+            logger.info("removed contributions: " + new File(url.toURI()).getName());
+        }
+        return urls;
+    }
+
+    protected void initParameters(ServletContext servletContext) {
+        if (servletContext.getInitParameter("domainName") != null) {
+            domainName = servletContext.getInitParameter("domainName");
+        } else {
+            domainName = null;
+        }
+
+        if (servletContext.getInitParameter("nodeName") != null) {
+            nodeName = servletContext.getInitParameter("nodeName");
+        } else {
+            nodeName = "DefaultNode";
+        }
+
+        if (servletContext.getInitParameter("hotDeployInterval") != null) {
+            hotDeployInterval = Long.parseLong(servletContext.getInitParameter("hotDeployInterval"));
+        }
+
+        useHotUpdate = Boolean.valueOf(servletContext.getInitParameter("hotUpdate")).booleanValue();
+
+        if (servletContext.getInitParameter("repositoryFolder") != null) {
+            repository = new File(servletContext.getInitParameter("repositoryFolder"));
+        } else {
+            repository = new File(servletContext.getRealPath(REPOSITORY_FOLDER_NAME));
+        }
+        logger.info("Tuscany Contribution Repository -> " + repository);
+    }
+
+}
+
+class AddableURLClassLoader extends URLClassLoader {
+
+    public AddableURLClassLoader(URL[] urls, ClassLoader parent) {
+        super(urls, parent);
+    }
+    
+    /**
+     * Make URLClassLoader addURL public 
+     */
+    @Override
+    public void addURL(URL url) {
+        super.addURL(url);
+    }
+    
+}