MySQL

@chatpack/adapter-mysql provides full Chatpack persistence through Drizzle ORM's MySQL dialect and the mysql2 driver.

Install

pnpm add @chatpack/core @chatpack/adapter-mysql drizzle-orm mysql2

Configure

import mysql from "mysql2/promise";
import { drizzle } from "drizzle-orm/mysql2";
import { chatpack } from "@chatpack/core";
import { migrationStatements, mysqlAdapter } from "@chatpack/adapter-mysql";

const pool = mysql.createPool(process.env.DATABASE_URL!);
for (const statement of migrationStatements) await pool.query(statement);

export const chat = chatpack({ storage: mysqlAdapter(drizzle(pool)), auth });

Create the pool and apply migrations in server-only application code. Never expose the pool or adapter to browser code.

Support boundary

The supported target is MySQL 8 with Drizzle mysql2 and a transaction-capable server-side connection or pool. This package does not claim MariaDB, Aurora, PlanetScale, HTTP/serverless MySQL drivers, read replicas, or edge-runtime support. Verify each alternative against its real driver and database before deployment.

Migrations

The package exports chatpackSchema, all twelve tables, migrationSql, and migrationStatements. Use migrationStatements for one-statement-per-call drivers. Each table includes its indexes, so rerunning statements is safe for a compatible existing schema. IF NOT EXISTS does not repair an incompatible table; inspect such a database and perform an explicit migration. Run backfillMessageSearchTokens(db) after importing messages from before search tokens existed.

Correctness

• MySQL's nullable unique pair_key allows unlimited group rows with NULL while concurrent non-NULL direct pairs converge on one row.
• The migration uses binary UTF-8 collation so opaque IDs and canonical search tokens remain exact instead of acquiring collation-specific matches.
• Group and initial participant insertion use one transaction.
• addMessage increments last_seq with an atomic update, then reads that value while InnoDB holds the conversation row lock until commit. It never uses MAX(seq) + 1.
• Invite use checks and increments in one conditional update. Mentions replace inside one transaction. Reactions and participant inserts use unique-key idempotent upserts. Active ban creation locks the indexed user range in one transaction.

All adapter results convert database timestamps to real Date instances.