[DEPR]: Contentstore and enrollment API versions superseded by FC-0118

Start by reviewing PR #38755 and the linked ADRs 0026, 0028, 0029, and 0032, then inspect the listed contentstore and enrollment API entry points. No implementation files or tests are named. Done means deprecated markers, warning headers, and replacement documentation are in place, followed by removal after the stated release window.

RFC Start Date

N/A -- Already Accepted

Target Plan Accepted Date

N/A -- Already Accepted

Target Transition Unblocked Date

Immediately -- Transition Already Unblocked

Earliest Breaking Changes Unblocked Date

One named release after the release this deprecation ships in

Rationale

As part of FC-0118 (API standardization), a set of Studio contentstore
endpoints and the LMS enrollment API were re-issued at new versions rather than
changed in place. The standardization ADRs mandate changes that are breaking for
existing consumers:

• ADR 0029 replaces the legacy {"developer_message": ..., "error_code": ...}
  error shape with an RFC 7807 envelope (type, title, status, detail,
  instance). Any client parsing error responses would break.
• ADR 0028 moves from APIView to ViewSet + DefaultRouter, changing URL
  patterns (trailing slashes, router-managed routing).
• ADR 0026 standardizes authentication and removes the deprecated
  BearerAuthentication, so Bearer-only consumers lose access.
• ADR 0032 standardizes pagination, changing the response envelope on list
  endpoints.

Issuing new versions let existing consumers migrate on their own timeline
instead of absorbing a silent breaking change. That migration window is what
this ticket closes: the old versions are now redundant, and keeping both means
every future change to these endpoints has to be made twice.

Description

All replacements are merged and available today via
#38755.

Deprecated endpoint	Replacement	Standardization issue
GET/POST /api/contentstore/v0/xblock/{course_id} and /{course_id}/{usage_key}	GET/POST/PATCH/DELETE /api/contentstore/v1/xblock/{usage_key}/	#38368
/api/enrollment/v1/ — enrollment, enrollments, course/{course_id}, unenroll/, roles/, enrollment_allowed/	/api/enrollment/v2/	#38369
GET/PUT /api/contentstore/v1/course_details/{course_id}	GET/PUT /api/contentstore/v3/course_details/{course_key}/	#38370
GET /api/contentstore/v1/home	GET /api/contentstore/v3/home/	#38371
GET /api/contentstore/v2/home/courses	GET /api/contentstore/v4/home/	#38372
POST /api/contentstore/v0/grading/{course_id}	PATCH /api/contentstore/v3/authoring_grading/{course_key}/	#38373

Consumers migrating should expect the RFC 7807 error envelope, router-managed
URLs (note the trailing slash), JWT or session auth in place of Bearer, and on
list endpoints the standardized pagination envelope.

Deprecation Schedule

The old versions are deprecated as of this ticket and will be removed one
named release after the release in which this deprecation ships, giving
operators and plugin authors a full release cycle on a supported version.

1. Now — endpoints marked deprecated: deprecated: true in the OpenAPI
   schema, a Warning response header, and docs pointing at the replacements.
2. Next named release — both versions ship; the deprecated ones still work.
3. The release after — old versions removed.

Task List

This ticket is the umbrella for API deprecations arising from the FC-0118
standardization work. Further areas will be appended as their replacement
versions merge:

• contentstore xblock, course_details, home (v1 and v2), grading; LMS enrollment v1 — #38755