kysely 0.30.0-beta.2

on Node.js NPM

Hey 👋

0.30 season is upon us. pnpm i kysely@next and get a sneak peak into the future!

We've got a new transactionMode: 'per-run' | 'per-migration' | 'none' property you can pass to Migrator or it's methods.

• 'per-run' is the classic behavior you're used to where kysely wrap the entire run in a transaction when your dialect supports transactional DDL.
• 'per-migration' enables each migration to pick whether it runs in its own transaction or not. Just expose config: { transaction: false } from the module, right next to the up/down functions.
• 'none' means no transactions are used, which is similar to the now deprecated disableTransactions: true.

import * as fs from 'node:fs/promises'
import * as path from 'node:path'
import { FileMigrationProvider, Migrator } from 'kysely/migration'

const migrator = new Migrator({
  db,
  provider: new FileMigrationProvider({
    fs,
    migrationFolder: path.join(import.meta.dirname, 'migrations'),
  }),
  transactionMode: 'per-migration', // <-------------------------------
})

await migrator.migrateToLatest()

We've got a new defineMigration helper function that you can use to easily write your migrations and meet the contract requirements:

import { defineMigration } from 'kysely/migration'

export default defineMigration({
  up: async (db) => {
    // ...
  },

  config: { transaction: false }, // <--------------------
})

You can now use mysql2/promise, where in the past it would hang forever since we only supported the callback style of mysql2 root import.

We're trying various type-level solutions that provide compilation performance and type-safety improvements of Kysely, Transaction, ControlledTransaction and their readonly variants.

We've got a new stream method on RawBuilder that allows you to:

import { sql } from 'kysely'
import { db } from 'path/to/db'

for await (const row of sql`select * from person`.stream(db)) {
  // ...
}

🚀 Features

• feat(migrator): add migrateTo(name, { direction: 'Up' | 'Down' }) to enforce direction. by @igalklebanov in #1957
• feat(introspector): add where option for partial introspection. by @igalklebanov in #2005
• feat(introspector): add where option in getSchemas. by @igalklebanov in #2006
• feat(introspector): add comment property in table metadata. by @igalklebanov in #2008
• feat: stream raw query results. by @igalklebanov in #2037

PostgreSQL 🐘 / MSSQL 🥅

• feat: Per-migration transaction configuration by @lourd & @igalklebanov in #1671

PostgreSQL 🐘

• feat(postgres): support introspecting materialized views. by @igalklebanov in #2010

MySQL 🐬

• feat(mysql): support both mysql2 and mysql2/promise in MysqlDialect. by @igalklebanov in #1958
• feat(mysql): add withNonDefaultDatabases to support introspection of non-default databases. by @igalklebanov in #2007

SQLite 📘

• feat: deny passing BLOB-like columns to SQLite JSON helpers by @hwisu & @igalklebanov in #1698
• feat(sqlite): stream queries that return rows. by @igalklebanov in
  #2036

🐞 Bugfixes

• fix: reject database assignments with missing tables. by @igalklebanov in #2015
• fix: allow transactions with extra tables to satisfy narrower schemas. by @igalklebanov in #2017
• fix: accept Kysely instances with extra tables on TypeScript 5. by @igalklebanov in #2018
• fix: preserve column read and write types in assignments. by @igalklebanov in #2019
• fix: preserve controlled transaction column write assignability. by @igalklebanov in #2022
• fix: preserve generic table extension assignability. by @igalklebanov in #2025
• fix: allow ControlledTransaction<any> to satisfy Transaction<DB>. by @igalklebanov in #2027
• fix: preserve readonly schema guarantees during assignment. by @igalklebanov in #2029
• fix: allow compatible readonly transactions as database handles. by @igalklebanov in #2033
• fix: allow compatible readonly controlled transactions as parent handles. by @igalklebanov in #2034

📖 Documentation

• docs: correct DummyDriver execution JSDoc. by @igalklebanov in #2032

📦 CICD & Tooling

• test: add Vitest typechecking to TypeScript CI. by @igalklebanov in #2014

⚠️ Breaking Changes

• disableTransactions is deprecated. Use the new transactionMode: 'none', or transactionMode: 'per-migration' with combination of config: { transaction: false }.
• You might start seeing invocations of some your custom helpers failing compilation now that Kysely, Transaction, ControlledTransaction and their readonly variants are compared more tightly. Please report these cases.

SQLite 📘

• Trying to pass records with BLOB columns in JSON helpers emits compile-time errors - e.g.

   KyselyTypeError<'SQLite does not support passing `BLOB` values to `json_object`. Cast to `TEXT`.'>

🐤 New Contributors

What's Changed

Full Changelog: v0.29.5...v0.30.0-beta.2