[#1846] Add monitoring (events) to template rendering...

documentation/manual/events.textile

@@ -0,0 +1,56 @@
+Events are a way for plugins to receive notifications from the framework or other plugins.
+
+The API to send events is pretty straightforward: an event is a `string` and an `Object` (the context).
+
+bc.. import play.PlayPlugin;
+
+... 
+PlayPlugin.postEvent("something happens", this);
+
+p. Plugins can listen to these events in the the @onEvent@ method: 
+
+bc.. public class My Plugin extends PlayPlugin {
+
+  @Override
+  public void onEvent(String message, Object context) {
+  ... 
+  }
+
+
+h2. Available events 
+
+At the moment the following events are sent by Play framework. 
+
+Events go in pair signaling the beginning and the end of a framework operation. 
+
+Usually the context provided to the before and after events is the same except for JPQL category. 
+In this case, the before event gives the entity name while the after give the JPQL instance.
+
+
+| Class      | Method         | Event                      | Context                     |
+| Controller | renderTemplate | template.render.before     | @string@: the template name |
+|            |                | template.render.after      | idem                        |
+| JPABase    | _save          | JPASupport.objectSaving    | @JPABase@: the object       |
+|            |                | JPASupport.objectPersisting| idem                        |
+|            |                | JPASupport.objectPersisted | idem                        |
+|            |                | JPASupport.objectSaved     | idem                        |
+|            | _delete        | JPASupport.objectDeleting  | idem                        |
+|            |                | JPASupport.objectDeleted   | idem                        |
+| JPQL       | count          | JPQL.count.before          | @string@: the entity name   |
+|            |                | JPQL.count.after           | @JPQL@: the object          |
+|            | findAll        | JPQL.findAll.before        | idem                        |
+|            |                | JPQL.findAll.after         | idem                        |
+|            | findBy         | JPQL.findBy.before         | idem                        |
+|            |                | JPQL.findBy.after          | idem                        |
+|            | find           | JPQL.find.before           | idem                        |
+|            |                | JPQL.find.after            | idem                        |
+|            | all            | JPQL.all.before            | idem                        |
+|            |                | JPQL.all.after             | idem                        |
+|            | delete         | JPQL.delete.before         | idem                        |
+|            |                | JPQL.delete.after          | idem                        |
+|            | deleteAll      | JPQL.deleteAll.before      | idem                        |
+|            |                | JPQL.deleteAll.after       | idem                        |
+|            | findOneBy      | JPQL.findOneBy.before      | idem                        |
+|            |                | JPQL.findOneBy.after       | idem                        |
+|            | create         | JPQL.create.before         | idem                        |
+|            |                | JPQL.create.after          |                             |

framework/src/play/db/jpa/JPABase.java

@@ -30,38 +30,50 @@ public class JPABase implements Serializable, play.db.Model {
 
 
     public void _save() {
+ 		boolean saving = false ;
         String dbName = JPA.getDBName(this.getClass());
         if (!em(dbName).contains(this)) {
+			saving = true ;
+            PlayPlugin.postEvent("JPASupport.objectSaving", this);
+			PlayPlugin.postEvent("JPASupport.objectPersisting", this);
             em(dbName).persist(this);
             PlayPlugin.postEvent("JPASupport.objectPersisted", this);
         }
-        avoidCascadeSaveLoops.set(new HashSet<JPABase>());
-        try {
-            saveAndCascade(true);
-        } finally {
-            avoidCascadeSaveLoops.get().clear();
-        }
-        try {
-            em(dbName).flush();
-        } catch (PersistenceException e) {
-            if (e.getCause() instanceof GenericJDBCException) {
-                throw new PersistenceException(((GenericJDBCException) e.getCause()).getSQL(), e);
-            } else {
-                throw e;
-            }
-        }
-        avoidCascadeSaveLoops.set(new HashSet<JPABase>());
-        try {
-            saveAndCascade(false);
-        } finally {
-            avoidCascadeSaveLoops.get().clear();
+		try{
+			avoidCascadeSaveLoops.set(new HashSet<JPABase>());
+			try {
+				saveAndCascade(true);
+			} finally {
+				avoidCascadeSaveLoops.get().clear();
+			}
+			try {
+				em(dbName).flush();
+			} catch (PersistenceException e) {
+				if (e.getCause() instanceof GenericJDBCException) {
+					throw new PersistenceException(((GenericJDBCException) e.getCause()).getSQL(), e);
+				} else {
+					throw e;
+				}
+			}
+			avoidCascadeSaveLoops.set(new HashSet<JPABase>());
+			try {
+				saveAndCascade(false);
+			} finally {
+				avoidCascadeSaveLoops.get().clear();
+			}
+		}
+        finally
+        {
+			if( saving ) 
+				PlayPlugin.postEvent("JPASupport.objectSaved", this);
         }
     }
 
     public void _delete() {
         String dbName = JPA.getDBName(this.getClass());
 
         try {
+            PlayPlugin.postEvent("JPASupport.objectDeleting", this);
             avoidCascadeSaveLoops.set(new HashSet<JPABase>());
             try {
                 saveAndCascade(true);
@@ -83,13 +95,14 @@ public void _delete() {
                 saveAndCascade(false);
             } finally {
                 avoidCascadeSaveLoops.get().clear();
-            }
-            PlayPlugin.postEvent("JPASupport.objectDeleted", this);
+            }     
         } catch (PersistenceException e) {
             throw e;
         } catch (Throwable e) {
             throw new RuntimeException(e);
-        }
+        } finally {
+			PlayPlugin.postEvent("JPASupport.objectDeleted", this);
+		}
     }
 
     public Object _key() {
@@ -106,9 +119,6 @@ private void saveAndCascade(boolean willBeSaved) {
             return;
         } else {
             avoidCascadeSaveLoops.get().add(this);
-            if (willBeSaved) {
-                PlayPlugin.postEvent("JPASupport.objectUpdated", this);
-            }
         }
         // Cascade save
         try {

framework/src/play/db/jpa/JPQL.java

@@ -7,6 +7,7 @@
 import javax.persistence.Query;
 
 import play.Play;
+import play.PlayPlugin;
 import play.data.binding.ParamNode;
 import play.data.binding.RootParamNode;
 import play.db.Configuration;
@@ -28,25 +29,34 @@ public long count(String entity) {
     }
 
     public long count(String dbName, String entity) {
-        return Long.parseLong(em(dbName).createQuery("select count(*) from " + entity + " e").getSingleResult().toString());
+   	    PlayPlugin.postEvent("JPQL.count.before", entity);
+        long result = Long.parseLong(em(dbName).createQuery("select count(*) from " + entity + " e").getSingleResult().toString());
+		PlayPlugin.postEvent("JPQL.count.after", this);
+		return result ;
     }
 
     public long count(String entity, String query, Object[] params) {
         return count(JPA.DEFAULT, entity, query, params);
     }
 
     public long count(String dbName, String entity, String query, Object[] params) {
-        return Long.parseLong(
+   	    PlayPlugin.postEvent("JPQL.count.before", entity);
+        long result = Long.parseLong(
                 bindParameters(em(dbName).createQuery(
                 createCountQuery(dbName, entity, entity, query, params)), params).getSingleResult().toString());
+		PlayPlugin.postEvent("JPQL.count.after", this);
+		return result ;
     }
 
     public List findAll(String entity) {
         return findAll(JPA.DEFAULT, entity);
     }
 
      public List findAll(String dbName, String entity) {
-        return em(dbName).createQuery("select e from " + entity + " e").getResultList();
+  	    PlayPlugin.postEvent("JPQL.findAll.before", entity);
+        List result = em(dbName).createQuery("select e from " + entity + " e").getResultList();
+		PlayPlugin.postEvent("JPQL.findAll.after", this);
+		return result ;
     }
 
     public JPABase findById(String entity, Object id) throws Exception {
@@ -62,9 +72,12 @@ public List findBy(String entity, String query, Object[] params) {
     }
 
     public List findBy(String dbName, String entity, String query, Object[] params) {
+  	    PlayPlugin.postEvent("JPQL.findBy.before", entity);
         Query q = em(dbName).createQuery(
                 createFindByQuery(dbName, entity, entity, query, params));
-        return bindParameters(q, params).getResultList();
+        List result = bindParameters(q, params).getResultList();
+		PlayPlugin.postEvent("JPQL.findBy.after", this);
+		return result ;
     }
 
     public JPAQuery find(String entity, String query, Object[] params) {
@@ -73,38 +86,50 @@ public JPAQuery find(String entity, String query, Object[] params) {
 
 
     public JPAQuery find(String dbName, String entity, String query, Object[] params) {
+  	    PlayPlugin.postEvent("JPQL.find.before", entity);
         Query q = em(dbName).createQuery(
                 createFindByQuery(dbName, entity, entity, query, params));
-        return new JPAQuery(
+        JPAQuery result = new JPAQuery(
                 createFindByQuery(dbName, entity, entity, query, params), bindParameters(q, params));
+		PlayPlugin.postEvent("JPQL.find.after", this);
+		return result ;
     }
 
     public JPAQuery find(String entity) {
         return find(JPA.DEFAULT, entity);
     }
 
     public JPAQuery find(String dbName, String entity) {
+  	    PlayPlugin.postEvent("JPQL.find.before", entity);
         Query q = em(dbName).createQuery(
                 createFindByQuery(dbName, entity, entity, null));
-        return new JPAQuery(
+        JPAQuery result = new JPAQuery(
                 createFindByQuery(dbName, entity, entity, null), bindParameters(q));
+		PlayPlugin.postEvent("JPQL.find.after", this);
+		return result ;
     }
 
     public JPAQuery all(String entity) {
         return all(JPA.DEFAULT, entity);
     }
 
     public JPAQuery all(String dbName, String entity) {
+  	    PlayPlugin.postEvent("JPQL.all.before", entity);
         Query q = em(dbName).createQuery(
                 createFindByQuery(dbName, entity, entity, null));
-        return new JPAQuery(
+        JPAQuery result = new JPAQuery(
                 createFindByQuery(dbName, entity, entity, null), bindParameters(q));
+		PlayPlugin.postEvent("JPQL.all.after", this);
+		return result ;
     }
 
     public int delete(String dbName, String entity, String query, Object[] params) {
+  	    PlayPlugin.postEvent("JPQL.delete.before", entity);
         Query q = em(dbName).createQuery(
                 createDeleteQuery(entity, entity, query, params));
-        return bindParameters(q, params).executeUpdate();
+        int result = bindParameters(q, params).executeUpdate();
+		PlayPlugin.postEvent("JPQL.delete.after", this);
+		return result ;
     }
 
     public int delete(String entity, String query, Object[] params) {
@@ -113,23 +138,29 @@ public int delete(String entity, String query, Object[] params) {
 
 
     public int deleteAll(String dbName, String entity) {
+  	    PlayPlugin.postEvent("JPQL.deleteAll.before", entity);
         Query q = em(dbName).createQuery(
                 createDeleteQuery(entity, entity, null));
-        return bindParameters(q).executeUpdate();
+        int result = bindParameters(q).executeUpdate();
+		PlayPlugin.postEvent("JPQL.deleteAll.after", this);
+		return result ;
     }
 
     public int deleteAll(String entity) {
        return deleteAll(JPA.DEFAULT, entity);
     }
 
     public JPABase findOneBy(String dbName, String entity, String query, Object[] params) {
+  	    PlayPlugin.postEvent("JPQL.findOneBy.before", entity);
         Query q = em(dbName).createQuery(
                 createFindByQuery(dbName, entity, entity, query, params));
         List results = bindParameters(q, params).getResultList();
-        if (results.size() == 0) {
-            return null;
-        }
-        return (JPABase) results.get(0);
+        JPABase result = null ;
+		if (results.size() != 0) {
+		    result = (JPABase) results.get(0);
+		}
+		PlayPlugin.postEvent("JPQL.findOneBy.after", this);
+		return result ;
     }
 
     public JPABase findOneBy(String entity, String query, Object[] params) {
@@ -141,11 +172,14 @@ public JPABase create(String entity, String name, Params params) throws Exceptio
     }
 
     public JPABase create(String dbName, String entity, String name, Params params) throws Exception {
+  	    PlayPlugin.postEvent("JPQL.create.before", entity);
         Object o = Play.classloader.loadClass(entity).newInstance();
 
         RootParamNode rootParamNode = ParamNode.convert(params.all());
 
-        return ((GenericModel) o).edit(rootParamNode, name);
+        JPABase result = ((GenericModel) o).edit(rootParamNode, name);
+		PlayPlugin.postEvent("JPQL.create.after", this);
+		return result ;
     }
 
     public String createFindByQuery(String dbName, String entityName, String entityClass, String query, Object... params) {

framework/src/play/mvc/Controller.java

@@ -17,6 +17,7 @@
 import play.Invoker.Suspend;
 import play.Logger;
 import play.Play;
+import play.PlayPlugin;
 import play.classloading.ApplicationClasses.ApplicationClass;
 import play.classloading.enhancers.ContinuationEnhancer;
 import play.classloading.enhancers.ControllersEnhancer.ControllerInstrumentation;
@@ -663,30 +664,39 @@ protected static void renderTemplate(String templateName, Object... args) {
      * @param args The template data.
      */
     protected static void renderTemplate(String templateName, Map<String,Object> args) {
-        // Template datas
-        Scope.RenderArgs templateBinding = Scope.RenderArgs.current();
-        templateBinding.data.putAll(args);
-        templateBinding.put("session", Scope.Session.current());
-        templateBinding.put("request", Http.Request.current());
-        templateBinding.put("flash", Scope.Flash.current());
-        templateBinding.put("params", Scope.Params.current());
-        templateBinding.put("errors", Validation.errors());
-        try {
-            Template template = TemplateLoader.load(template(templateName));
-            throw new RenderTemplate(template, templateBinding.data);
-        } catch (TemplateNotFoundException ex) {
-            if (ex.isSourceAvailable()) {
-                throw ex;
-            }
-            StackTraceElement element = PlayException.getInterestingStackTraceElement(ex);
-            if (element != null) {
-                ApplicationClass applicationClass = Play.classes.getApplicationClass(element.getClassName());
-                if (applicationClass != null) {
-                    throw new TemplateNotFoundException(templateName, applicationClass, element.getLineNumber());
-                }
-            }
-            throw ex;
-        }
+        PlayPlugin.postEvent("template.render.before", templateName);
+		Template template = null ;
+		try
+		{
+	        // Template datas
+	        Scope.RenderArgs templateBinding = Scope.RenderArgs.current();
+	        templateBinding.data.putAll(args);
+	        templateBinding.put("session", Scope.Session.current());
+	        templateBinding.put("request", Http.Request.current());
+	        templateBinding.put("flash", Scope.Flash.current());
+	        templateBinding.put("params", Scope.Params.current());
+	        templateBinding.put("errors", Validation.errors());
+	        try {
+	            template = TemplateLoader.load(template(templateName));
+	            throw new RenderTemplate(template, templateBinding.data);
+	        } catch (TemplateNotFoundException ex) {
+	            if (ex.isSourceAvailable()) {
+	                throw ex;
+	            }
+	            StackTraceElement element = PlayException.getInterestingStackTraceElement(ex);
+	            if (element != null) {
+	                ApplicationClass applicationClass = Play.classes.getApplicationClass(element.getClassName());
+	                if (applicationClass != null) {
+	                    throw new TemplateNotFoundException(templateName, applicationClass, element.getLineNumber());
+	                }
+	            }
+	            throw ex;
+				}
+			}
+		finally
+		{
+			PlayPlugin.postEvent("template.render.after", template);
+		}
     }
 
     /**