Files
Lumotia/docs/issues/c3-migrations-atomicity.md
Claude 89c63891fa chore: rebrand from Kon/Corbie to Magnotia
Replace all instances of the legacy product names "Kon" and "Corbie" with
"Magnotia" across user-facing copy, code identifiers, package names, bundle
ids, file paths, and documentation. Preserves the unrelated "konsole" (KDE
terminal) reference and the parent CORBEL company name.

- Renames 10 Rust crates (kon-* → magnotia-*) and the tauri binary
- Updates package.json, tauri.conf.json (productName + identifier)
- Renames CSS classes (kon-rh-* → magnotia-rh-*) and animations
- Renames brand and roadmap docs
- Regenerates Cargo.lock and package-lock.json

Verified: svelte-check passes; pure-rust crates compile under new names.
2026-04-30 13:06:55 +00:00

2.9 KiB

RB-02 CRITICAL: multi-statement migrations can half-apply

Severity: CRITICAL Path: crates/storage/src/migrations.rs:263-299 Source: 2026-04-22 code review Labels: release-blocker, critical, data-integrity, storage Status: RESOLVED (2026-04-22)

Resolution

Extracted run_migrations_slice(pool, migrations) as the single code path that applies pending migrations. For each pending version it opens a Transaction via pool.begin(), applies every split statement on that transaction, records the schema_version row inside the same transaction, and finally tx.commit()s. A failure anywhere in the sequence — statement, version insert, commit — rolls the whole migration back.

run_migrations delegates to run_migrations_slice(pool, MIGRATIONS) and the test helper run_migrations_up_to to a filtered subset, so only one version of the apply logic exists.

Regression test multi_statement_migration_rolls_back_on_failure feeds a poisoned v9 migration (CREATE TABLE poison_marker; SELECT this_function_does_not_exist()) through run_migrations_slice. The call returns Err, and post-call SELECT COUNT(*) FROM poison_marker fails with "no such table" while MAX(schema_version) remains at 8.

SQLite DDL participates in transactions, so this is sufficient for the Magnotia schema. If any future migration needs a statement that implicitly commits (VACUUM, REINDEX, ATTACH) — none do today — it must be split into its own non-transactional migration. Reviewer's job to flag.

Problem

run_migrations executes each statement individually and only records the schema version after the full migration succeeds. If a multi-statement migration (v5, v6, v8 — any containing more than one CREATE / ALTER / UPDATE) fails mid-run, or the process is killed between statements, the schema can end up partially changed while still appearing unapplied. The next startup replays the same migration against the mutated database, which can fail in confusing ways or corrupt data further.

Acceptance

  • Every migration runs inside a single BEGIN / COMMIT transaction.
  • The version row update happens inside the same transaction — atomic success or no change.
  • Regression test: a migration that panics partway through leaves the database at the previous schema version with no partial changes visible on restart.

Fix scope

Medium. Wrap each migration in pool.begin() / tx.commit(). The version update and the migration statements all execute on the same Transaction handle. Needs careful review of any migration that uses implicit commits (SQLite VACUUM, REINDEX, ATTACH — none of which Magnotia currently uses, but the review pattern should guard against future additions).

Dependencies

  • Coupled with RB-03 (any v9 migration adding the transcript-profile FK must itself be transactional — this fix is a prerequisite).