Introduction to apps

CMS plugins consist of static content. Backend code around plugins is restricted to rendering (except if you add a thing or two in your own views, of course).

However, wouldn’t it be awesome if it were possible to add contact forms and even more complicated apps to the page tree through the CMS?

That’s exactly what feincms3 apps are for.

Apps are defined by a list of URL patterns specific to this app. A simple contact form would probably only have a single URLconf entry (r'^$'), a news app would at least have two entries (the archive and the detail URL).

The activation of apps happens through a dynamically created URLconf module (probably the trickiest code in all of feincms3, apps_urlconf()). The apps_middleware assigns the module to request.urlconf which ensures that apps are available for resolving and URL reversing. No page code runs at all, control is directly passed to the app views.

Please note that apps do not have to take over the page where the app itself is attached. If the app does not have a URLconf entry for r'^$' the standard page rendering still happens. because of the recommended catch-all URLconf entry for pages at the end.