Liferay7开发文档_3.6.3创建PERMISSIONS HELPER CLASSES

创建PERMISSIONS HELPER CLASSES

现在已经定义了权限并确保将资源添加到数据库。接下来创建用于检查权限的helper classes。

它是这样工作的。您有一个权限，比如ADD_ENTRY和一个资源，比如Guestbook。用户要向guestbook添加一个条目，必须检查该用户是否具有guestbook的ADD_ENTRY权限。创建helper classes来检查特定模型和实体的权限，使这些检查更便捷。因此，创建这样的类是最佳实践。现在将为Guestbook应用程序创建helper classes：

1. Right-click the guestbook-service module and select New → Package. Name the package com.liferay.docs.guestbook.service.permission. This is where you’ll place your helper classes。
2. Right-click the new package and select New → Class. Name the class GuestbookModelPermission。
3. Replace this class’s contents with the following code：

   package com.liferay.docs.guestbook.service.permission;
   
   import org.osgi.service.component.annotations.Component;
   
   import com.liferay.portal.kernel.exception.PortalException;
   import com.liferay.portal.kernel.security.auth.PrincipalException;
   import com.liferay.portal.kernel.security.permission.BaseResourcePermissionChecker;
   import com.liferay.portal.kernel.security.permission.PermissionChecker;
   import com.liferay.portal.kernel.security.permission.ResourcePermissionChecker;
   
   @Component(immediate = true, property = {
       "resource.name=" + GuestbookModelPermission.RESOURCE_NAME
   }, service = ResourcePermissionChecker.class)
   
   public class GuestbookModelPermission extends BaseResourcePermissionChecker {
   
       public static final String RESOURCE_NAME = "com.liferay.docs.guestbook";
   
       public static void check(
           PermissionChecker permissionChecker, long groupId, String actionId)
           throws PortalException {
   
           if (!contains(permissionChecker, groupId, actionId)) {
               throw new PrincipalException.MustHavePermission(
                   permissionChecker, RESOURCE_NAME, groupId, actionId);
           }
       }
   
       public static boolean contains(
           PermissionChecker permissionChecker, long groupId, String actionId) {
   
           return permissionChecker.hasPermission(
               groupId, RESOURCE_NAME, groupId, actionId);
       }
   
       @Override
       public Boolean checkResource(
           PermissionChecker permissionChecker, long classPK, String actionId) {
   
           return contains(permissionChecker, classPK, actionId);
       }
   }
   

这个类是扩展BaseResourcePermissionChecker的组件，并定义了两个静态方法(因此您不必实例化类)来封装您要检查的模型。它还包含一个布尔方法来检查您的资源。Liferay的PermissionChecker类做了大部分工作: 只需要输入资源和操作参数，例如ADD_ENTRY，它会返回permission是否存在。

这里有三种实现：check方法，如果用户没有权限就会抛出异常；contains方法，返回布尔值的方法，如果用户有权限为true，如果没有权限为fals；checkResource方法，调用contains方法。

接下来，为两个实体创建Helper。按照以下步骤操作：

1. Create a class in the same package called GuestbookPermission.java。
2. Replace this class’s contents with the following code：

   package com.liferay.docs.guestbook.service.permission;
   
   import com.liferay.docs.guestbook.model.Guestbook;
   import com.liferay.docs.guestbook.service.GuestbookLocalService;
   import com.liferay.portal.kernel.exception.PortalException;
   import com.liferay.portal.kernel.exception.SystemException;
   import com.liferay.portal.kernel.security.auth.PrincipalException;
   import com.liferay.portal.kernel.security.permission.BaseModelPermissionChecker;
   import com.liferay.portal.kernel.security.permission.PermissionChecker;
   import org.osgi.service.component.annotations.Component;
   import org.osgi.service.component.annotations.Reference;
   
   @Component(
       immediate = true,
       property = {"model.class.name=com.liferay.docs.guestbook.model.Guestbook"}
   )
   public class GuestbookPermission implements BaseModelPermissionChecker {
   
       public static void check(
           PermissionChecker permissionChecker, long guestbookId, String actionId)
           throws PortalException, SystemException {
   
           if (!contains(permissionChecker, guestbookId, actionId)) {
               throw new PrincipalException();
           }
       }
   
       public static void check(
           PermissionChecker permissionChecker, long groupId, long guestbookId,
           String actionId)
           throws PortalException {
   
           if (!contains(permissionChecker, groupId, actionId)) {
               throw new PrincipalException.MustHavePermission(
                   permissionChecker, Guestbook.class.getName(), guestbookId,
                   actionId);
           }
       }
   
       public static boolean contains(
           PermissionChecker permissionChecker, long groupId, long guestbookId, String actionId) 
               throws PortalException {
   
           Guestbook guestbook = _guestbookLocalService.getGuestbook(guestbookId);
   
           return GuestbookModelPermission.contains(permissionChecker, groupId, actionId);
       }
   
       public static boolean contains(
           PermissionChecker permissionChecker, long guestbookId, String actionId)
           throws PortalException, SystemException {
   
           Guestbook guestbook
               = _guestbookLocalService.getGuestbook(guestbookId);
           return contains(permissionChecker, guestbook, actionId);
       }
   
       public static boolean contains(
           PermissionChecker permissionChecker, Guestbook guestbook, String actionId) 
               throws PortalException, SystemException {
   
           return permissionChecker.hasPermission(
           guestbook.getGroupId(), Guestbook.class.getName(), guestbook.getGuestbookId(), actionId);
   
       }
   
       @Reference(unbind = "-")
       protected void setGuestbookLocalService(GuestbookLocalService guestbookLocalService) {
           _guestbookLocalService = guestbookLocalService;
       }
   
       private static GuestbookLocalService _guestbookLocalService;
   
       @Override
       public void checkBaseModel(
           PermissionChecker permissionChecker, long groupId, long guestbookId, String actionId) throws PortalException {
               check(permissionChecker, guestbookId, actionId);
       }
   }
   

这个类类似于GuestbookModelPermission。不同之处在于，GuestbookPermission是用于模型/资源权限的，所以提供了正在检查权限的实体的主键(guestbookId)。在GuestbookPermission中的check和contains方法也类似于GuestbookModelPermission中的方法。在这两个类中，如果没有权限，check方法会抛出一个异常，而contains方法返回一个布尔值，表示当前用户是否有权限。然而，在GuestbookPermission中包含的方法也检索实体来验证它是否存在(如果它不存在，则抛出一个异常)。

最后一个类几乎与GuestbookPermission相同，但它是为Entry实体设置的。按照以下步骤创建它：

1. Create a class in the same package called EntryPermission.java。
2. Replace this class’s contents with the following code：

   package com.liferay.docs.guestbook.service.permission;
   
   import com.liferay.docs.guestbook.model.Entry;
   import com.liferay.docs.guestbook.service.EntryLocalService;
   import com.liferay.portal.kernel.exception.PortalException;
   import com.liferay.portal.kernel.exception.SystemException;
   import com.liferay.portal.kernel.security.auth.PrincipalException;
   import com.liferay.portal.kernel.security.permission.BaseModelPermissionChecker;
   import com.liferay.portal.kernel.security.permission.PermissionChecker;
   import org.osgi.service.component.annotations.Component;
   import org.osgi.service.component.annotations.Reference;
   
   @Component(
       immediate = true,
       property = {"model.class.name=com.liferay.docs.guestbook.model.Entry"}
   )
   public class EntryPermission implements BaseModelPermissionChecker {
   
       public static void check(
           PermissionChecker permissionChecker, long entryId, String actionId)
           throws PortalException, SystemException {
   
           if (!contains(permissionChecker, entryId, actionId)) {
               throw new PrincipalException();
           }
       }
   
       public static boolean contains(
           PermissionChecker permissionChecker, long entryId, String actionId)
           throws PortalException, SystemException {
   
           Entry entry = _entryLocalService.getEntry(entryId);
   
           return contains (permissionChecker, entry, actionId);
   
       }
   
       public static boolean contains(
           PermissionChecker permissionChecker, Entry entry, String actionId) throws
           PortalException, SystemException {
   
           return permissionChecker.hasPermission(entry.getGroupId(), Entry.class.getName(), entry.getEntryId(), actionId);
       }
   
       @Reference(unbind = "-")
       protected void setEntryLocalService (EntryLocalService entryLocalService) {
   
           _entryLocalService = entryLocalService;
       }
   
       private static EntryLocalService _entryLocalService; 
   
       @Override
       public void checkBaseModel(
           PermissionChecker permissionChecker, long groupId, long primaryKey, String actionId) throws PortalException {
               check(permissionChecker, primaryKey, actionId);
       }
   }
   

这个类几乎与GuestbookPermission相同。唯一的区别是EntryPermission对应于Entry实体。

现在有了这些类，必须构建服务并导出permissions package，以便其他模块可以访问。按照以下步骤操作：

1. Save the permissions helper classes you just created. From the Gradle Tasks panel on the right side of Liferay IDE, run buildService from the guestbook-service module’s build folder。
2. In the Project Explorer, open the bnd.bnd file from the root folder of the guestbook-servicemodule。
3. In the graphical view, under the Export Packages section, click the plus button to add an export。
4. Select com.liferay.docs.guestbook.service.permission and click OK。
5. Save the file。

现在已经为权限创建了Helper类。剩下的唯一事情就是在应用程序的视图层中实现权限检查。