fix(alembic): linearize two migration heads onto 3f9a1c7b2e04#12978
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Pull request overview
Linearizes the Manager Alembic migration chain to restore a single head.
Changes:
- Reparents
a1c4e7b93f22ontob988f01b17a1. - Updates the migration docstring accordingly.
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Satisfies the timeline-check towncrier gate on #12978. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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please add a new merge revision rather than changing an existing revision
PRs #12818 (b988f01b17a1) and #12869 (a1c4e7b93f22) each branched a migration off 3f9a1c7b2e04 and merged independently, leaving two alembic heads and failing scripts/check-multiple-alembic-heads.py. Per the alembic README (keep a single linear head; never merge), reparent the later-merged a1c4e7b93f22 (kernel history perms) onto the earlier b988f01b17a1 (fair-share uniqueness). The two migrations are independent, so ordering is safe. Chain is now: 3f9a1c7b2e04 -> b988f01b17a1 -> a1c4e7b93f22 Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Satisfies the timeline-check towncrier gate on #12978. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Revert the earlier reparent of a1c4e7b93f22 (its down_revision goes back to 3f9a1c7b2e04) and instead add an empty merge migration 577c7a215934 whose down_revision is the tuple of the two heads. Per the alembic guardrails, when main itself has two or more heads the correct fix is an empty merge migration, not editing the diverged (possibly already-released) migrations' down_revision. Chain is now: 3f9a1c7b2e04 -> b988f01b17a1 -> 577c7a215934 3f9a1c7b2e04 -> a1c4e7b93f22 -> 577c7a215934 Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Summary
mainhas two alembic heads, soscripts/check-multiple-alembic-heads.pyexits 1:Both migrations branched off the same parent
3f9a1c7b2e04and merged independently:b988f01b17a1(fair-share uniqueness)a1c4e7b93f22(kernel history read perms)Fix
Per
src/ai/backend/manager/models/alembic/README.md— keep a single linear head, never create merge migrations, fixdown_revisionpointers instead.Reparent the later-merged
a1c4e7b93f22onto the earlierb988f01b17a1. The two migrations are independent (an RBAC permission seed vs. a uniqueness-constraint change), so reordering is safe.Test plan
python3 scripts/check-multiple-alembic-heads.py→Detected head revisions: a1c4e7b93f22, exit 0pants fmt lint --changed-since=HEADclean🤖 Generated with Claude Code