Attempting to create the next available prefix within a parent assigned to a VRF raises an AssertionError

[jeremystretch]

Environment

• Python version: 3.5.6
• NetBox version: 2.4.2

Steps to Reproduce

1. Create a prefix assigned to a VRF.
2. Make an API request to create the "next available" prefix within this prefix. For example:

curl -X POST \
-H "Authorization: Token <token>" \
-H "Content-Type: application/json" \
-H "Accept: application/json; indent=4" \
http://localhost:8000/api/ipam/prefixes/<pk>/available-prefixes/ \
--data '{"prefix_length": 26}'

Expected Behavior

A new child prefix should be created.

Observed Behavior

An exception is raised:

AssertionError: `HyperlinkedIdentityField` requires the request in the serializer context. Add `context={'request': request}` when instantiating the serializer.