Background & Approach

Background

Plugins are a key component of django CMS for creating reusable, configurable content fragments in django CMS projects. Due to their flexibility and utility, project developers would benefit from emitting forms and handling form submissions using plugins.

Since CMS plugins are fragments of a page, they do not provide a unique, URL for receiving and handling form submissions. This presents numerous challenges when attempting to process form submissions.

Approach

To get around these limitations, the approach taken in this package is to direct form submissions from plugins which sub-class FormPluginBase to a URL that is outside of the django CMS URL-space and handled by a ProcessFormView provided by this package.

The ProcessFormView accepts form-submissions, processes them, and if valid, sends the resulting form back to the plugin class for handling and then responds to the request with a redirect to a success_url provided by the plugin.

On validation errors, the view will redirect the request back to the originating page and provide the form data via a session variable back to the plugin’s form.

The user experience is precisely as expected and the handling of the form is performed without “thrown HTTPRedirectResponses” or any special middleware.

This package encapsulates all extra logic so that the plugin developer need only to subclass FormPluginBase rather than the usual cms.plugin_base.CMSPluginBase.

The Form or ModelForm presented in the CMS plugin should also include the “mixin” FormPluginFormMixin.