idb-migrations
DevelopmentHow to create and implement IndexedDB storage migrations in the Trezor Suite web app. Use when writing migrations that transform persisted data between Suite versions.
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IDB Storage Migrations
Overview
Suite uses IndexedDB for persistent storage. When the data schema changes between versions, a migration transforms old data to match the new shape. Migrations live in packages/suite/src/storage/migrations/versions/.
Creating a Migration
Step 1: Scaffold
# Auto-detect version (recommended)
yarn workspace @trezor/suite make:migration
# Specific version
yarn workspace @trezor/suite make:migration 26.5.0
# Revision within a version
yarn workspace @trezor/suite make:migration 26.5.0.1
This creates the migration file and updates the auto-generated index at packages/suite/src/storage/migrations/versions/index.ts.
Step 2: Implement
Every migration file uses createMigration from @suite/idb-migration-utils and default-exports the result.
Minimal (schema-only) migration
Use when creating/deleting object stores — no data transformation needed:
import { createMigration } from '@suite/idb-migration-utils';
import { type SuiteDBSchema } from 'src/storage/definitions';
export default createMigration<SuiteDBSchema>('26.5.0', db => {
db.createObjectStore('newStore');
});
Data transformation migration
Use updateAll from ../utils to iterate and transform all records in a store. The callback receives each record and must return:
- the updated record to update it
nullto delete itundefined/void to leave it untouched
import { createMigration } from '@suite/idb-migration-utils';
import { type SuiteDBSchema } from 'src/storage/definitions';
import { updateAll } from '../utils';
export default createMigration<SuiteDBSchema>('26.5.0', async (_, tx) => {
await updateAll(tx, 'devices', device => {
// Add a new field with a default value
if (!device.newField) {
device.newField = 'default';
}
return device;
});
});
Accessing multiple stores
The migration callback receives (db, tx) where db is the database and tx is the versionchange transaction. You can access any store via tx.objectStore('storeName'):
export default createMigration<SuiteDBSchema>('26.5.0', async (db, tx) => {
// Read from a store directly
const store = tx.objectStore('suiteSettings');
const settings = await store.get('suite');
// Modify and write back
if (settings) {
settings.someField = 'newValue';
await store.put(settings, 'suite');
}
// Also transform another store
await updateAll(tx, 'devices', device => {
device.field = 'value';
return device;
});
});
Accessing deleted stores
When a store was removed from SuiteDBSchema, use @ts-expect-error to access it:
// @ts-expect-error storeName no longer exists
if (db.objectStoreNames.contains('oldStore')) {
// @ts-expect-error storeName no longer exists
const store = tx.objectStore('oldStore');
const data = await store.get('key');
// ... migrate data to new location
// @ts-expect-error storeName no longer exists
db.deleteObjectStore('oldStore');
}
Step 3: Update the CHANGELOG
For base migrations (revision 0), a ## x.y.z header is auto-added to packages/suite/src/storage/CHANGELOG.md. Add a description of what the migration does under it.
Key Stores
| Store | Key | Description |
|---|---|---|
devices | string | Remembered devices (DeviceWithEmptyPath) |
persistentDeviceData | string | Device metadata that persists across connections (PersistentDeviceData[]) |
suiteSettings | string | Suite settings, flags, EVM settings |
accounts | string | Wallet accounts |
txs | string | Wallet transactions |
Full schema: packages/suite/src/storage/definitions.ts (SuiteDBSchema)
Version Encoding
IndexedDB version is a 32-bit integer encoding SemVer: (major << 24) | (minor << 16) | (patch << 8) | revision. Each component is 0-255. See suite/idb-migration-utils/MIGRATION.md for details.
Important Notes
- Migration files must default-export the
createMigrationresult - The
versions/index.tsfile is auto-generated — use the scaffold command, don't edit manually - Use
@ts-expect-errorfor accessing stores/fields that no longer exist in the current schema - Always guard with
ifchecks before accessing potentially missing data - The
updateAllutility handles cursor iteration — just provide the transform function