Netbox: Implement Select2 as a replacement for standard and API backed selection fields.

[lampwins]

Environment

• Python version: 3.6
• NetBox version: 2.5.2

Proposed Functionality

For some time we have wanted to enhance the UI selection fields to allow for more dynamic API interaction. Select2 is a very popular solution for this, and initial testing confirms it is an appropriate choice.

Several recent and outstanding issues will be covered as a part of this, including #2516, #2590, and #2735.

Use Case

We will use Select2 to replace:

• All instances of Livesearch fields which are used to query the API in real time for a model instance.
• All model backed choice fields which will allow us to handle large datasets via pagination (infinite scrolling).
• All chained choice fields, refactoring the related server-side code and replacing the JS code for this along the way.
• Tag fields which will allow us to make use of autocomplete and an overall improved UI for tags.
• Model backed multi selection fields which will look and feel much like the tagging interface.
• Static choice selection fields when appropriate. This will help in maintaining a consistent UI for selection.

Database Changes

None

External Dependencies

There will be a new dependency on Select2. This includes minified JS and CSS files in project-static assets along with Select2's related i18n files. This will be handled the same as the other JS dependencies like jQuery.

[lampwins]

Work has commenced in the select2-ui branch.