As you learned earlier, roles can be scoped by the instance, by a site, or by an organization. A role only takes effect within its scope. For example, a Message Boards Administrator role with complete access to the Message Boards app has different permissions based on the role’s scope. If it’s a instance role, members have permission to administer message boards across the entire instance. If it’s a site role, members only have permission to administer message boards within the site where they’ve been assigned the role. For organizations with sites, site roles are automatically assigned to organization members based on the organization roles they have. So for an organization-scoped Message Boards administrator role, members only have permission to administer message boards within the site of the organization that assigned the role to them.
You’ve also heard the word scope refer to the data set of an app. By default, when an app is added to a page in a site, it is scoped for that site. This means that its data belongs to that site. If the app is added to a page in a different site, it employs a completely different data set. This enables you to place a Message Boards app in one site with one set of categories and threads, and place another Message Boards app in different site with a different set of categories and threads.
Scoping by site means that you can only have one Message Boards app per site. If you add one Message Boards app to a page in a site and add another Message Boards app to a different page in the same site, the second Message Boards app contains exactly the same data as the first. This is because, by default, the Message Boards app is scoped by site. Most of Liferay DXP’s other apps also default to being scoped by site.
To avoid this limitation, many Liferay apps can be scoped by page. In this case, the data sets of page-scoped apps serve a single page, not an entire site. If you set the scope of an app to page instead of site, you can add any number of these apps to different pages, and then they have different sets of data. This allows you to have more than one message board per site if you wish. Most apps, however, default to the “native” configuration, and have their scopes set to the site where they are placed.
Figure 1: When defining a page scope for an app, the Menu provides a *Default Scope* dropdown.
Unless otherwise noted, all the apps in this chapter support scoping by instance (global), site (default), or page . This grants you some flexibility in how you want to set up your Liferay instance. You can configure the scope of an app with just a few simple steps.
-
Click the Options icon (
) in the app window.
-
Select Configuration.
-
Select the Scope tab.
-
Use the drop-down menu to set the scope.
Figure 2: You can change the scope of your application by navigating to its Configuration menu.
Once you’ve defined a page scope for an application, the Menu provides a Default Scope dropdown that allows you to select the page you want to create content on.
That’s all it takes to change the scope for a particular application instance. By setting the scope to the current page, you can add as many of these apps to a site as you want, provided they are all added to separate pages.
Another useful feature of Liferay’s apps is Configuration Templates.