fix(magicmapper): prevent _uuid index collisions across dynamic tables

[SudoThijn]

Summary

• MagicMapper::createTable now emits a named CONSTRAINT ... UNIQUE (...) so MySQL/MariaDB no longer auto-name the constraint/index after the column.
• Adds repair migration Version1Date20260521120000 to drop the bare _uuid index on every existing oc_openregister_table_*.

Bug

Installing any app (first reported with doriath) failed with:

InvalidArgumentException: Index name "_uuid" for table "oc_openregister_table_1_5"
collides with the constraint on table "oc_openregister_table_1_2".

Root cause: MagicMapper::createTable built CREATE TABLE ... , UNIQUE (`_uuid`) without naming the constraint. MySQL/MariaDB then used the column name (_uuid) as the index name. Every dynamic table accumulated a bare _uuid index alongside the correctly-prefixed {table}_uuid_idx from createTableIndexes. Nextcloud's MigrationService::ensureUniqueNamesConstraints throws fatally on duplicate index names across tables, but only at install time (isInstalling=true) — so the broken state silently accumulated and the next app:enable blew up.

Fix

1. Name the constraint. lib/Db/MagicMapper.php — the inline UNIQUE now uses CONSTRAINT `{tableName}_{col}_uq` UNIQUE (...), with the matching double-quoted variant for PostgreSQL. New dynamic tables get a table-scoped, collision-free constraint name.
2. Repair existing installs. lib/Migration/Version1Date20260521120000.php — postSchemaChange queries INFORMATION_SCHEMA.STATISTICS (MySQL/MariaDB) or pg_indexes (PostgreSQL) for oc_openregister_table_* tables that still carry a bare _uuid index and drops it. The correctly-prefixed {table}_uuid_idx (also unique, also on _uuid) stays in place, so column uniqueness and PG ON CONFLICT are preserved.

Test plan

• Run repair migration against a broken DB — Dropped bare _uuid index on 9 of 9 dynamic openregister table(s).
• INFORMATION_SCHEMA.STATISTICS shows only {table}_uuid_idx per dynamic table afterwards.
• occ app:enable doriath succeeds (previously failed with the collision exception).
• Verify on PostgreSQL (no PG environment available here — migration's PG path uses pg_indexes lookup + per-index DROP INDEX IF EXISTS and only matches ^_uuid(\d+)?$ names, but please confirm in a PG setup before merging).
• Confirm a freshly-created dynamic table on MySQL shows CONSTRAINT openregister_table_X_Y_uuid_uq UNIQUE (`_uuid`) in SHOW CREATE TABLE.

[github-actions]

Quality Report — ConductionNL/openregister @ a8eb4ff

Check	PHP	Vue	Security	License	Tests
lint	✅
phpcs	❌
phpmd	✅
psalm	✅
phpstan	✅
phpmetrics	✅
eslint		❌
stylelint		❌
composer			❌	✅ 162/162
npm			✅	✅ 532/532
PHPUnit					⏭️
Newman					⏭️
Playwright					⏭️

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Quality workflow — 2026-05-21 12:38 UTC

Download the full PDF report from the workflow artifacts.

[WilcoLouwerse]

APPROVE — Thorough review.

Fix is correct and well-scoped: names the inline UNIQUE constraint ({tableName}_{col}_uq) so MySQL/MariaDB no longer auto-name the index after the column, and pairs it with an idempotent repair migration that drops the bare _uuid index on existing broken installs. Verified locally:

• ✅ php -l clean on both files
• ✅ phpstan clean on PR files (99 pre-existing errors all in other files)
• ❌ composer phpcs — 19 errors on the new migration file (18 auto-fixable via composer phpcs:fix + 1 manual on line 113)
• ✅ Smoke-checked SQL — MySQL ALTER TABLE … DROP INDEX _uuid is correct; PG pg_indexes lookup + DROP INDEX IF EXISTS is standard; column quoting flows correctly per-platform via the existing $colName branching at MagicMapper.php:2582-2585

No blockers. Six inline comments — 3× 🟡 (phpcs, PG asymmetry, PG path unverified per your own test plan), 3× 🟢 (hardcoded oc_ prefix, redundant unique indexes).

Nothing in the 🟡 list changes the verdict, but the phpcs failure is the project's own CI signal — worth running composer phpcs:fix before merge to keep the file green.

[WilcoLouwerse]

Re-review verdict: ✅ APPROVE (Quick mode)

Both actionable prior findings have been addressed by the new commits:

• 🟡 phpcs CI failure (named parameter + 18 auto-fix violations) — resolved in d5b023f
• 🟡 PG asymmetry between findAffectedTables and postSchemaChange — resolved in 9213278 (both queries now share the LIKE '\_uuid%' ESCAPE '\\' pattern; strict ^_uuid(\d+)?$ regex at drop time preserves safety)

Resolved as non-blocking (not blockers; tracked as follow-ups or verification asks):

• 🟡 PG path verification — remains a useful pre-merge smoke test
• 🟢 Hardcoded oc_ prefix — cosmetic, consistent with existing precedent
• 🟢 Two unique indexes on _uuid per dynamic table — pre-existing redundancy

No new issues identified on the additional diff. CI Newman API Test Suite is failing due to a pre-existing infrastructure issue (config.platform PHP 8.1 vs composer.json requiring ^8.3) unrelated to this PR — not a required check per the Development ruleset.