fix(ZNTA-1073) : create custom exceptions + handlers (#1169)

* fix(ZNTA-1073):Fix NullPointerEx on iteration view

Throw EntityNotFoundException instead of NullPointerException when
attempt to access non-existing project through writing invalid project
slug on the iteration page

* fix(ZNTA-1073):create custom exceptions + handlers

Create ProjectNotFoundEx and VersionNotFoundEx and throw them when
trying to write invalid project or iteration slug on project view or
iteration view pages. Handle these exceptions and return warn page with
the proper warning message.

* fix(ZNTA-1073):change the structure of the ex.s

Instead of passing parameters on the warning page for the error messages,
creating constructors with slug arguments and passing project slug and
version slug parameters when throwing the exceptions. Also, rename warn
page to missing_entity.

* fix(ZNTA-1073) : Add header comment

* fix(ZNTA-1073) : remove unnecessary comment

* fix(ZNTA-1073): change the exception message

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

@@ -4,6 +4,7 @@
 import java.util.Collections;
 import java.util.List;
 
+import javax.annotation.Nullable;
 import javax.faces.application.FacesMessage;
 
 import com.google.common.collect.Lists;
@@ -112,7 +113,7 @@ public void setSourceProjectSlug(String sourceProjectSlug) {
             this.sourceProjectSlug = sourceProjectSlug;
             refreshSourceProject();
             this.sourceVersionSlug = null;
-            if (!getSourceProject().getProjectIterations().isEmpty()) {
+            if (getSourceProject() != null && !getSourceProject().getProjectIterations().isEmpty()) {
                 this.sourceVersionSlug =
                     getSourceProject().getProjectIterations().get(0).getSlug();
             }
@@ -133,7 +134,7 @@ public HProjectIteration getTargetVersion() {
         return targetVersion;
     }
 
-    public HProject getSourceProject() {
+    public @Nullable HProject getSourceProject() {
         if(sourceProject == null && StringUtils.isNotEmpty(sourceProjectSlug)) {
             sourceProject = projectDAO.getBySlug(sourceProjectSlug);
         }

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

@@ -62,6 +62,7 @@
 import org.zanata.dao.LocaleDAO;
 import org.zanata.dao.PersonDAO;
 import org.zanata.dao.WebHookDAO;
+import org.zanata.exception.ProjectNotFoundException;
 import org.zanata.i18n.Messages;
 import org.zanata.model.HAccount;
 import org.zanata.model.HAccountRole;
@@ -691,7 +692,7 @@ private void validateProjectState(HProject project) {
             log.warn(
                     "Project [id={}, slug={}], does not exist or is soft deleted: {}",
                     projectId, getSlug(), project);
-            throw new EntityNotFoundException();
+            throw new ProjectNotFoundException(getSlug());
         }
     }
 

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

@@ -53,6 +53,8 @@
 import org.zanata.dao.ProjectDAO;
 import org.zanata.dao.ProjectIterationDAO;
 import org.zanata.dao.LocaleDAO;
+import org.zanata.exception.ProjectNotFoundException;
+import org.zanata.exception.VersionNotFoundException;
 import org.zanata.i18n.Messages;
 import org.zanata.model.HLocale;
 import org.zanata.model.HProject;
@@ -261,6 +263,9 @@ public class VersionItem implements Serializable {
     @Override
     protected HProjectIteration loadInstance() {
         Session session = (Session) getEntityManager().getDelegate();
+        HProject project = (HProject) session.byNaturalId(HProject.class)
+           .using("slug", getProjectSlug()).load();
+        validateProjectState(project);
         if (versionId == null) {
             HProjectIteration iteration = (HProjectIteration) session
                     .byNaturalId(HProjectIteration.class)
@@ -284,7 +289,16 @@ private void validateIterationState(HProjectIteration iteration) {
             log.warn(
                     "Project version [id={}, slug={}], does not exist or is soft deleted: {}",
                     versionId, getSlug(), iteration);
-            throw new EntityNotFoundException();
+            throw new VersionNotFoundException(getProjectSlug(), getSlug());
+        }
+    }
+
+    private void validateProjectState(HProject project) {
+        if (project == null || project.getStatus() == EntityStatus.OBSOLETE) {
+            log.warn(
+                "Project [slug={}], does not exist or is soft deleted: {}",
+                getProjectSlug(), project);
+            throw new ProjectNotFoundException(getProjectSlug());
         }
     }
 

zanata-war/src/main/java/org/zanata/exception/ProjectNotFoundException.java

@@ -0,0 +1,34 @@
+/*
+ * Copyright 2016, 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.exception;
+
+public class ProjectNotFoundException extends RuntimeException {
+    private static final long serialVersionUID = 1L;
+    private final String projectSlug;
+
+    public ProjectNotFoundException(String projectSlug) {
+        this.projectSlug = projectSlug;
+    }
+
+    public String getProjectSlug() {
+        return projectSlug;
+    }
+}

zanata-war/src/main/java/org/zanata/exception/VersionNotFoundException.java

@@ -0,0 +1,40 @@
+/*
+ * Copyright 2016, 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.exception;
+
+public class VersionNotFoundException extends RuntimeException {
+    private static final long serialVersionUID = 1L;
+    private final String projectSlug;
+    private final String versionSlug;
+
+    public VersionNotFoundException(String projectSlug, String versionSlug) {
+        this.projectSlug = projectSlug;
+        this.versionSlug = versionSlug;
+    }
+
+    public String getProjectSlug() {
+        return projectSlug;
+    }
+
+    public String getVersionSlug() {
+        return versionSlug;
+    }
+}

zanata-war/src/main/java/org/zanata/exception/handler/ProjectNotFoundExceptionHandler.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2016, 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.exception.handler;
+
+import org.apache.deltaspike.core.api.exception.control.ExceptionHandler;
+import org.apache.deltaspike.core.api.exception.control.Handles;
+import org.apache.deltaspike.core.api.exception.control.event.ExceptionEvent;
+import org.zanata.exception.ProjectNotFoundException;
+
+import javax.faces.application.FacesMessage;
+
+
+@ExceptionHandler
+public class ProjectNotFoundExceptionHandler extends AbstractExceptionHandler {
+    public void handleException(@Handles ExceptionEvent<ProjectNotFoundException> event) {
+        handle(event, LogLevel.Warn, urlUtil.missingEntityPage(), FacesMessage.SEVERITY_WARN,
+                "jsf.ProjectNotFound", event.getException().getProjectSlug());
+    }
+}

zanata-war/src/main/java/org/zanata/exception/handler/VersionNotFoundExceptionHandler.java

@@ -0,0 +1,39 @@
+/*
+ * Copyright 2016, 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.exception.handler;
+
+import org.apache.deltaspike.core.api.exception.control.ExceptionHandler;
+import org.apache.deltaspike.core.api.exception.control.Handles;
+import org.apache.deltaspike.core.api.exception.control.event.ExceptionEvent;
+import org.zanata.exception.VersionNotFoundException;
+
+import javax.faces.application.FacesMessage;
+
+
+@ExceptionHandler
+public class VersionNotFoundExceptionHandler extends AbstractExceptionHandler {
+    public void handleException(@Handles ExceptionEvent<VersionNotFoundException> event) {
+        VersionNotFoundException exception = event.getException();
+        handle(event, LogLevel.Warn, urlUtil.missingEntityPage(), FacesMessage.SEVERITY_WARN,
+                "jsf.VersionNotFound", exception.getProjectSlug(), exception.getVersionSlug());
+    }
+}

zanata-war/src/main/java/org/zanata/util/UrlUtil.java

@@ -286,6 +286,13 @@ public String genericErrorPage() {
         return contextPath + "/error" + dswidQuery;
     }
 
+    /**
+     * Get missing entity page url with dswid parameter
+     */
+    public String missingEntityPage() {
+        return contextPath + "/error/missing_entity" + dswidQuery;
+    }
+
     /**
      * Get view expired url with dswid parameter
      */

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

@@ -14,6 +14,8 @@ jsf.Deleted=Deleted
 ! this is shown when trying to access a project, version or other item that does not exist in the system.
 ! e.g. navigate to a project, then change the project slug in the URL to make it invalid and press enter.
 jsf.RecordNotFound=Record not found
+jsf.ProjectNotFound = Project "{0}" not found
+jsf.VersionNotFound = Version "{1}" for project "{0}" not found
 jsf.DuplicatedRecord=Duplicated record
 jsf.AnotherUserChangedTheSameDataPleaseTryAgain=Another user changed the same data. Please try again.
 jsf.YouDoNotHavePermissionToAccessThisResource=You do not have permission to access this resource.

zanata-war/src/main/webapp/error/missing_entity.xhtml

@@ -0,0 +1,43 @@
+<!DOCTYPE composition PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
+  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
+<ui:composition xmlns="http://www.w3.org/1999/xhtml"
+  xmlns:ui="http://java.sun.com/jsf/facelets"
+  xmlns:h="http://java.sun.com/jsf/html"
+  template="../WEB-INF/template/template.xhtml">
+
+  <ui:define name="page_title">#{msgs['jsf.Error']}</ui:define>
+  <ui:param name="showGlobalMessages" value="false"/>
+  <ui:define name="center_content">
+    <ui:remove>
+      <!-- TODO [CDI] use h:messages instead of jsfMessages.globalMessagesList? -->
+    </ui:remove>
+    <ui:fragment
+      rendered="#{empty jsfMessages.globalMessagesList}">
+      <h2>#{msgs['jsf.NoErrors']}</h2>
+    </ui:fragment>
+
+    <ui:fragment
+      rendered="#{not empty jsfMessages.globalMessagesList}">
+      <ul class="list--no-bullets">
+        <li>
+          <div class="alert--danger">
+            <h2 class="alert__heading">#{msgs['jsf.ErrorTitle']}</h2>
+
+            <div class="alert__content">
+              <ul class="list--no-bullets">
+                <ui:repeat
+                  value="#{jsfMessages.globalMessagesList}"
+                  var="message">
+                  <h:outputText
+                    value="#{message.detail}">
+                  </h:outputText>
+
+                </ui:repeat>
+              </ul>
+            </div>
+          </div>
+        </li>
+      </ul>
+    </ui:fragment>
+  </ui:define>
+</ui:composition>