GNIP-62: Contribute back upstream menu management from IGAD #4249

Generalize and simplify the menu management system implemented for IGAD.
The generic implementation to be ported upstream should provide a model to define menus and a generic "placeholder" concept to be integrated inside custom tempaltes through template tags.

Models

• menu_placeholder: represents a logical container for menus. A template tag will provide the list of menus linked to this placeholder to be rendered in a specific area of the template HTML.

  • id
  • name

• menu: the links container. With bootstrap it could be rendered as a dropdown title

  • id
  • title
  • placeholder_id: FK to menu_placeholder
  • order: menus within the same placeholder will be rendered according to this (optional) value. It represents a relative weight

• menu_item:
  • id
  • title
  • menu_id: FK to menu
  • order
  • blank_target: boolean flag to specify if the link should open a new page
  • url: free input. Internal pages will be define with relative urls, external pages with absolute url.

Template tags

A set of template tags should be implemented to provide the template developer the option to obtain:

• list of menu objects for a certain placeholder
• list of menu_item objects for a certain menu

We would also provide a "rendered" option to obtain a complete placehoder and / or single menu rendered according to a default template, i.e. Bootstrap themed as the other menus in vanilla GeoNode.