cutover: support multiple sources with rollback on partial failure#692
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Pull request overview
Refactors the move cutover flow to support N source databases by introducing per-source cutover configuration and adding a best-effort rollback when a multi-source rename partially fails.
Changes:
- Introduce
CutOverSourceand updateCutOver/NewCutOverto operate on[]CutOverSource. - Update cutover algorithm to lock/flush/verify/rename across all sources, with rollback of completed renames on partial failure.
- Update the move runner to wrap the existing single-source setup into a one-element
[]CutOverSource, and add multi-source cutover tests.
Reviewed changes
Copilot reviewed 3 out of 3 changed files in this pull request and generated 4 comments.
| File | Description |
|---|---|
| pkg/move/runner.go | Adapts runner cutover construction to the new NewCutOver([]CutOverSource, ...) API. |
| pkg/move/cutover.go | Implements multi-source locking/flush verification and sequential rename with rollback on partial failure. |
| pkg/move/cutover_test.go | Adds tests for NewCutOver validation and a 2-source “happy path” integration test. |
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Refactor CutOver to accept []CutOverSource instead of a single
db/feed pair. This prepares the cutover for N:M move operations
where multiple source databases need to be locked, flushed, and
renamed atomically.
Key changes:
- New CutOverSource struct with DB, ReplClient, Tables
- NewCutOver accepts []CutOverSource
- algorithmCutover locks all sources, flushes all feeds, checks
all changes flushed, then renames per source
- On partial rename failure, completed renames are rolled back
by reversing the RENAME TABLE statements
The runner wraps its single source into []CutOverSource{...} for
backward compatibility. No behavioral change for 1:1 moves.
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…me-named tables in different schemas Confirms that LOCK TABLES on t1 in schema_0 and LOCK TABLES on t1 in schema_1 can be held concurrently on the same MySQL server, since each connection is scoped to its own database. This is required for N:M move operations where multiple source databases have identically-named tables.
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Kiran01bm
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Apr 13, 2026
Kiran01bm
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Apr 14, 2026
Kiran01bm
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Apr 14, 2026
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Part of #690
Refactor CutOver to accept []CutOverSource instead of a single db/feed pair. This prepares the cutover for N:M move operations where multiple source databases need to be locked, flushed, and renamed atomically.
Key changes:
The runner wraps its single source into []CutOverSource{...} for backward compatibility. No behavioral change for 1:1 moves.