How do I (or should I?) access the service layer from a SiteMesh template (views/layouts/main.gsp) in Grails?

I need to create a toplist in the page footer on a site that I'm building. The footer is created in the default SiteMesh layout template (views/layouts/main.gsp).

In order to create the toplist access to the databas开发者_Python百科e is needed, so I've encapsulated all logic needed for the toplist creation in a service class (services/FooService).

Please note that while services are usually accessed from the controller layer, in this case the default layout template (views/layouts/main.gsp) is not generated from a controller.

• Can the layout view (views/layouts/main.gsp) access a service class? How?
• Is this the correct design decision? If not, what is a better encapsulation and how do I interact with said encapsulation from the layout view (views/layouts/main.gsp)?

I would suggest creating a tag library (documented here) to wrap the rendering of your footer. You can inject your service into the tag library class by simply declaring a field with the same name.

Then get what you need from the service and either output the html directly or better yet create a _footer.gsp and render it with render template: 'footer', model: [yourmodel: model].

You should access your service from your controllers instead of the views.