Validate Content-Type header for REST API requests

[jeremystretch]

NetBox version

v3.2.9

Feature type

New functionality

Proposed functionality

Implement logic to check that the Content-Type header for inbound REST API requests has been properly set to application/json, and return an error if missing or invalid.

Use case

Currently, if a REST API request is made to create an object without specifying the correct content type, validation will fail reporting missing required fields. This is because the serializer (which expects JSON data) is not properly processing the request. This can be very confusing to the user.

Database changes

No response

External dependencies

No response

[jeremystretch]

One way to approach this would be to omit any parsers other than JSONParser in the DRF settings:

    'DEFAULT_PARSER_CLASSES': [
        'rest_framework.parsers.JSONParser',
        # 'rest_framework.parsers.FormParser',
        # 'rest_framework.parsers.MultiPartParser'
    ],

This triggers a 415 error if the Content-Type header is not set:

{
    "detail": "Unsupported media type \"application/x-www-form-urlencoded\" in request."
}