First cut of Facebook integration:

1) Web Script framework extensions for supporting the development of Alfresco based Facebook applications
2) Sample Document Library Facebook application
3) FormData enhancements for supporting request args retrieval for multipart/form-data encoding
4) Sort order added to Search Javascript API

Note: Stuff needs commenting, tidy up, but at least it's in SVN.

git-svn-id: https://svn.alfresco.com/repos/alfresco-enterprise/alfresco/HEAD/root@7259 c4b6b30b-aa2e-2d43-bbcb-ca4b014f7261

source/java/org/alfresco/web/scripts/facebook/FacebookService.java

@@ -0,0 +1,118 @@
+package org.alfresco.web.scripts.facebook;
+
+import java.util.HashMap;
+import java.util.Map;
+import java.util.concurrent.locks.ReentrantReadWriteLock;
+
+import org.alfresco.service.cmr.repository.ScriptLocation;
+import org.alfresco.web.scripts.WebScriptContext;
+import org.alfresco.web.scripts.WebScriptException;
+import org.alfresco.web.scripts.WebScriptRegistry;
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+
+
+public class FacebookService
+{
+    // Logger
+    private static final Log logger = LogFactory.getLog(FacebookService.class);
+    
+    // Facebook Application Cache
+    private Map<String, FacebookAppModel> apps = new HashMap<String, FacebookAppModel>();    
+    private ReentrantReadWriteLock appsLock = new ReentrantReadWriteLock(); 
+
+    private WebScriptRegistry registry;
+    private WebScriptContext context;
+    
+    
+    public void setRegistry(WebScriptRegistry registry)
+    {
+        this.registry = registry;
+    }
+
+
+
+    FacebookAppModel getAppModel(String apiKey)
+    {
+        FacebookAppModel facebookApp = null;
+        appsLock.readLock().lock();
+
+        try
+        {
+            facebookApp = apps.get(apiKey);
+            if (facebookApp == null)
+            {
+                // Upgrade read lock to write lock
+                appsLock.readLock().unlock();
+                appsLock.writeLock().lock();
+
+                try
+                {
+                    // Check again
+                    facebookApp = apps.get(apiKey);
+                    if (facebookApp == null)
+                    {
+                        if (logger.isDebugEnabled())
+                            logger.debug("Initialising Facebook Application '" + apiKey + "'");
+                        
+                        // Locate app initialisation script in web script store
+                        String appPath = "/com/facebook/_apps/app." + apiKey + ".js";
+                        ScriptLocation appScript = registry.getScriptProcessor().findScript(appPath);
+                        if (appScript == null)
+                        {
+                            throw new WebScriptException("Unable to locate application initialisation script '" + appPath + "'");
+                        }
+                        
+                        // Execute app initialisation script
+                        Map<String, Object> model = new HashMap<String, Object>();
+                        FacebookAppModel app = new FacebookAppModel(apiKey);
+                        model.put("app", app);
+                        registry.getScriptProcessor().executeScript(appScript, model);
+
+                        // Validate initialisation
+                        if (app.getSecret() == null)
+                        {
+                            throw new WebScriptException("Secret key for application '" + apiKey + "' has not been specified.");
+                        }
+                        if (app.getApiKey() == null)
+                        {
+                            throw new WebScriptException("Application Id for application '" + apiKey + "' has not been specified.");
+                        }
+
+                        apps.put(apiKey, app);
+                        facebookApp = app;
+                    }
+                }
+                finally
+                {
+                    // Downgrade lock to read
+                    appsLock.readLock().lock();
+                    appsLock.writeLock().unlock();
+                }
+            }
+            return facebookApp;
+        }
+        finally
+        {
+            appsLock.readLock().unlock();
+        }
+    }
+
+    public Map<String, FacebookAppModel> getAppModels()
+    {
+        return apps;
+    }
+ 
+    public void reset()
+    {
+        appsLock.writeLock().lock();
+        try
+        {
+            apps.clear();
+        }
+        finally
+        {
+            appsLock.writeLock().unlock();
+        }
+    }
+}