Function runMigrationsWithRetry

packages/db/scripts/migrate.ts:182–209

* Run pending migrations, retrying on lock timeout (55P03, found anywhere in * the wrapped `cause` chain). Each attempt re-verifies the lock session (pid) * and re-asserts the session timeouts — a migration file may have changed them, * and `SET` cannot be parameterized, hence `client.unsafe` wit

()

 * CONCURRENTLY statements are idempotent by convention.
 */
async function runMigrationsWithRetry(): Promise<void> {
  for (let attempt = 1; ; attempt++) {
    if (hasDirectMigrationUrl) {
      const [{ pid }] = await client`SELECT pg_backend_pid() AS pid`
      if (pid !== lockSessionPid) {
        throw new Error(
          `Database session changed mid-run (backend pid ${lockSessionPid} -> ${pid}); ` +
            'the migration advisory lock was lost. Aborting so a fresh runner can retry safely.'
        )
      }
    }
    await client.unsafe('SET statement_timeout = 0')
    await client.unsafe(`SET lock_timeout = '${DDL_LOCK_TIMEOUT}'`)
    try {
      await migrate(drizzle(client), { migrationsFolder: './migrations' })
      return
    } catch (error) {
      const isLockTimeout = getPostgresErrorCode(error) === '55P03'
      if (!isLockTimeout || attempt >= MAX_MIGRATE_ATTEMPTS) throw error
      const delayMs = backoffWithJitter(attempt, null, MIGRATE_RETRY_BACKOFF)
      console.warn(
        `WARN: migration DDL hit lock_timeout (attempt ${attempt}/${MAX_MIGRATE_ATTEMPTS}); ` +
          `retrying in ${Math.round(delayMs)}ms.`
      )
      await sleep(delayMs)
    }
  }
}

/**
 * A failed CONCURRENTLY build leaves an INVALID index that `IF NOT EXISTS`