[adapter-mysql] client connection support and release pool (#1126)

Co-authored-by: pilcrowOnPaper <[email protected]>

.auri/$oex8k1h4.md

@@ -0,0 +1,6 @@
+---
+package: "@lucia-auth/adapter-mysql"
+type: "minor"
+---
+
+Added support for client Connection and fixed a bug in Pool connections.

packages/adapter-mysql/src/drivers/mysql2.ts

@@ -13,11 +13,12 @@ import type {
 	RowDataPacket,
 	OkPacket,
 	ResultSetHeader,
-	PoolConnection
+	PoolConnection,
+	Connection
 } from "mysql2/promise";
 
 export const mysql2Adapter = (
-	db: Pool,
+	db: Pool | Connection,
 	tables: {
 		user: string;
 		session: string | null;
@@ -29,23 +30,6 @@ export const mysql2Adapter = (
 		? escapeName(tables.session)
 		: null;
 	const ESCAPED_KEY_TABLE_NAME = escapeName(tables.key);
-
-	const transaction = async <
-		_Execute extends (connection: PoolConnection) => Promise<void>
-	>(
-		execute: _Execute
-	) => {
-		const connection = await db.getConnection();
-		try {
-			await connection.beginTransaction();
-			await execute(connection);
-			await connection.commit();
-			return;
-		} catch (e) {
-			await connection.rollback();
-			throw e;
-		}
-	};
 	return (LuciaError) => {
 		return {
 			getUser: async (userId) => {
@@ -66,7 +50,7 @@ export const mysql2Adapter = (
 					return;
 				}
 				try {
-					await transaction(async (connection) => {
+					await transaction(db, async (connection) => {
 						const [userFields, userValues, userArgs] = helper(user);
 						await connection.execute(
 							`INSERT INTO ${ESCAPED_USER_TABLE_NAME} ( ${userFields} ) VALUES ( ${userValues} )`,
@@ -319,3 +303,37 @@ export const getAll = async <Schema>(
 	if (!isPacketArray(rows)) return [];
 	return rows as any;
 };
+
+const transaction = async <
+	_Execute extends (connection: Connection | PoolConnection) => Promise<void>
+>(
+	db: Pool | Connection,
+	execute: _Execute
+) => {
+	if (isPool(db)) {
+		const connection = await db.getConnection();
+		try {
+			await connection.beginTransaction();
+			await execute(connection);
+			await connection.commit();
+			connection.release();
+		} catch (e) {
+			await connection.rollback();
+			connection.release();
+			throw e;
+		}
+	} else {
+		try {
+			await db.beginTransaction();
+			await execute(db);
+			await db.commit();
+		} catch (e) {
+			await db.rollback();
+			throw e;
+		}
+	}
+};
+
+const isPool = (db: Pool | Connection): db is Pool => {
+	return "getConnection" in db;
+};