rhbz841037 - Extend user deletion to handle constraint violations.

Extend Seam's out-of-the-box UserAction bean to catch constraint violation exceptions and display them as a Faces message instead of a generic catch-all message.

zanata-war/src/main/java/org/zanata/action/UserAction.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright 2010, Red Hat, Inc. and individual contributors as indicated by the
+ * @author tags. See the copyright.txt file in the distribution for a full
+ * listing of individual contributors.
+ * 
+ * This is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 2.1 of the License, or (at your option)
+ * any later version.
+ * 
+ * This software 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.
+ * 
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this software; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA, or see the FSF
+ * site: http://www.fsf.org.
+ */
+package org.zanata.action;
+
+import java.util.Map;
+import javax.persistence.EntityManager;
+import javax.persistence.PersistenceException;
+
+import org.hibernate.exception.ConstraintViolationException;
+import org.jboss.seam.annotations.In;
+import org.jboss.seam.annotations.Install;
+import org.jboss.seam.annotations.Name;
+import org.jboss.seam.annotations.Scope;
+import org.jboss.seam.faces.FacesMessages;
+import org.jboss.seam.international.StatusMessage;
+import org.jboss.seam.security.management.IdentityManager;
+
+import static org.jboss.seam.ScopeType.CONVERSATION;
+import static org.jboss.seam.annotations.Install.APPLICATION;
+
+/**
+ * Extension of Seam management's UserAction class' behaviour.
+ *
+ * @see {@link org.jboss.seam.security.management.action.UserAction}
+ * @author Carlos Munoz <a href="mailto:camunoz@redhat.com">camunoz@redhat.com</a>
+ */
+@Name("org.jboss.seam.security.management.userAction")
+@Scope(CONVERSATION)
+@Install(precedence = APPLICATION)
+public class UserAction extends org.jboss.seam.security.management.action.UserAction
+{
+   @In
+   private IdentityManager identityManager;
+
+   @In
+   private EntityManager entityManager;
+
+   @In
+   private Map<String, String> messages;
+
+   public void deleteUser( String userName )
+   {
+      try
+      {
+         identityManager.deleteUser(userName);
+         // NB: Need to call flush here to be able to catch the persistence exception, otherwise it would be caught by Seam.
+         entityManager.flush();
+      }
+      catch (PersistenceException e)
+      {
+         FacesMessages.instance().add(StatusMessage.Severity.ERROR, messages.get("jsf.UserManager.delete.constraintViolation.error") );
+      }
+   }
+}

zanata-war/src/main/resources/messages.properties

@@ -481,6 +481,9 @@ jsf.Update=Update
 jsf.UrlExample=e.g. http://example.com/zanata or http://zanata.example.com
 jsf.UrlToolTip=The base URL for the server, including the application context path (no final slash)
 jsf.UserManager=User Manager
+
+jsf.UserManager.delete.constraintViolation.error=This user cannot be removed from the system. You can deactivate the user instead.
+
 jsf.Username=Username
 jsf.UsernameToolTip=The username should be all in lower case.
 jsf.Variant=Variant

zanata-war/src/main/webapp/admin/usermanager.xhtml

@@ -64,7 +64,7 @@
 	            <s:fragment rendered="#{s:hasPermission('seam.user', 'update')}">
 	              <h:commandButton value="#{messages['jsf.Edit']}" action="#{userAction.editUser(userSearch.selectedUser)}"/>
 	            </s:fragment>
-	            <h:commandButton value="#{messages['jsf.Delete']}" action="#{identityManager.deleteUser(userSearch.selectedUser)}" 
+	            <h:commandButton value="#{messages['jsf.Delete']}" action="#{userAction.deleteUser(userSearch.selectedUser)}"
 	                    rendered="#{s:hasPermission('seam.user', 'delete')}"
 	                    onclick="return confirmDelete()"/>
 	          </h:column>