persql

PerSQL Dart and Flutter SDK. Query your edge SQLite databases, and sign a user in with OAuth + PKCE so each one gets their own private cloud database — the user owns the data, you fund it. No backups or storage to manage on the device.

flutter pub add persql     # or: dart pub add persql

Give each user their own database ("Sign in with PerSQL")

The SDK does the OAuth 2.1 + PKCE handshake; your app only handles the browser redirect (e.g. with flutter_web_auth_2).

import 'package:persql/persql.dart';

// 1. Begin sign-in. Open req.url; keep req.codeVerifier + req.state.
final req = PerSQL.beginConnect(
  clientId: 'psqlrp_…',
  redirectUri: 'https://app.example.com/callback', // App Link / Universal Link
  scope: 'openid database',
);

// 2. After the redirect (verify state == req.state), exchange the code.
final persql = await PerSQL.completeConnect(
  clientId: 'psqlrp_…',
  redirectUri: 'https://app.example.com/callback',
  code: code,                       // from the redirect
  codeVerifier: req.codeVerifier,
);

// 3. Use the database provisioned in the user's own account.
final db = persql.database(persql.grant!.database);
await db.query('CREATE TABLE IF NOT EXISTS notes (id INTEGER PRIMARY KEY, body TEXT)');
await db.query('INSERT INTO notes (body) VALUES (?)', params: ['first note']);

Store persql.grant!.accessToken with flutter_secure_storage; on later launches skip the OAuth dance:

final db = PerSQL(token: storedToken).database(storedDatabaseRef);

Query

final res = await db.query('SELECT id, body FROM notes WHERE id = ?', params: [1]);
for (final row in res.data) {
  print('${row['id']}: ${row['body']}');
}

await db.batch([
  Statement('INSERT INTO notes (body) VALUES (?)', ['a']),
  Statement('INSERT INTO notes (body) VALUES (?)', ['b']),
], transaction: true);

final tables = await db.tables(); // List<TableInfo>

Errors throw `PerSQLException` with the HTTP status and message.

Notes

• Cloud-first by design. The user's data is durable from the first write — it survives a lost device and restores on reinstall, which is exactly what on-device-only storage can't promise.
• Redirect capture is your app's job — use flutter_web_auth_2 (or App Links / Universal Links). Custom URL schemes are rejected by PerSQL as phishable; register an HTTPS redirect or the platform proxy.
• v0.1 covers query / batch / tables + the connect flow. Snapshots, branches, and change subscriptions are not wrapped yet.

See the User-owned app databases recipe.