fix: mysql date conversion (#492)

examples/nextjs-example/package.json

@@ -11,10 +11,10 @@
     "start": "next start",
     "lint": "next lint"
   },
-  "dependencies": { 
+  "dependencies": {
+    "@better-auth/expo": "workspace:*",
     "@hookform/resolvers": "^3.9.0",
     "@libsql/client": "^0.12.0",
-    "@better-auth/expo": "workspace:*",
     "@libsql/kysely-libsql": "^0.4.1",
     "@prisma/adapter-libsql": "^5.19.1",
     "@prisma/client": "^5.19.1",
@@ -65,6 +65,7 @@
     "kysely": "^0.27.4",
     "lucide-react": "^0.439.0",
     "mini-svg-data-uri": "^1.4.4",
+    "mysql2": "^3.11.0",
     "next": "15.0.0-canary.185",
     "next-themes": "^0.3.0",
     "prisma": "^5.19.1",

packages/better-auth/src/adapters/kysely-adapter/index.ts

@@ -1,6 +1,7 @@
 import type { Kysely } from "kysely";
 import type { FieldAttribute } from "../../db";
 import type { Adapter, Where } from "../../types";
+import type { KyselyDatabaseType } from "./types";
 
 function convertWhere(w?: Where[]) {
 	if (!w)
@@ -96,13 +97,33 @@ function transformTo(
 	return val;
 }
 
+function formatDateForMySQL(date: Date): string {
+	const pad = (n: number) => (n < 10 ? "0" + n : n);
+	return (
+		date.getFullYear() +
+		"-" +
+		pad(date.getMonth() + 1) +
+		"-" +
+		pad(date.getDate()) +
+		" " +
+		pad(date.getHours()) +
+		":" +
+		pad(date.getMinutes()) +
+		":" +
+		pad(date.getSeconds())
+	);
+}
+
 function transformFrom(val: any, transform: KyselyAdapterConfig["transform"]) {
 	for (const key in val) {
 		if (typeof val[key] === "boolean" && transform?.boolean) {
 			val[key] = val[key] ? 1 : 0;
 		}
 		if (val[key] instanceof Date) {
-			val[key] = val[key].toISOString();
+			val[key] =
+				transform?.databaseType === "mysql"
+					? formatDateForMySQL(val[key])
+					: val[key].toISOString();
 		}
 	}
 	return val;
@@ -118,6 +139,7 @@ export interface KyselyAdapterConfig {
 		};
 		boolean: boolean;
 		date: boolean;
+		databaseType?: KyselyDatabaseType | null;
 	};
 	/**
 	 * Custom generateId function.
@@ -144,11 +166,22 @@ export const kyselyAdapter = (
 			if (config?.generateId !== undefined) {
 				val.id = config.generateId ? config.generateId() : undefined;
 			}
-			let res = await db
-				.insertInto(model)
-				.values(val as any)
-				.returningAll()
-				.executeTakeFirst();
+
+			const builder = db.insertInto(model).values(val as any);
+			let res: any;
+
+			if (config?.transform?.databaseType !== "mysql") {
+				res = await builder.returningAll().executeTakeFirst();
+			} else {
+				await builder.execute();
+				const primaryKey = "id";
+				const insertedId = val[primaryKey];
+				res = await db
+					.selectFrom(model)
+					.selectAll()
+					.where(primaryKey, "=", insertedId)
+					.executeTakeFirst();
+			}
 
 			if (config?.transform) {
 				const schema = config.transform.schema[model];
@@ -201,7 +234,6 @@ export const kyselyAdapter = (
 			if (config?.transform) {
 				const schema = config.transform.schema[model];
 				res = res && schema ? transformTo(res, schema, config.transform) : res;
-
 				return res || null;
 			}
 			return (res || null) as any;
@@ -251,7 +283,19 @@ export const kyselyAdapter = (
 			if (or) {
 				query = query.where((eb) => eb.or(or.map((expr) => expr(eb))));
 			}
-			const res = (await query.returningAll().executeTakeFirst()) || null;
+			let res: any;
+			if (config?.transform?.databaseType !== "mysql") {
+				res = (await query.returningAll().executeTakeFirst()) || null;
+			} else {
+				await query.execute();
+				const primaryKey = "id";
+				const insertedId = val[primaryKey];
+				res = await db
+					.selectFrom(model)
+					.selectAll()
+					.where(primaryKey, "=", insertedId)
+					.executeTakeFirst();
+			}
 			if (config?.transform) {
 				const schema = config.transform.schema[model];
 				return schema ? transformTo(res, schema, config.transform) : res;

packages/better-auth/src/api/routes/session-api.test.ts

@@ -43,6 +43,7 @@ describe("session", async () => {
 
 	it("should update session when close to expiry", async () => {
 		let headers = new Headers();
+
 		const res = await client.signIn.email(
 			{
 				email: testUser.email,

packages/better-auth/src/api/routes/session.ts

@@ -129,6 +129,7 @@ export const getSession = <Option extends BetterAuthOptions>() =>
 				}
 				const expiresIn = ctx.context.sessionConfig.expiresIn;
 				const updateAge = ctx.context.sessionConfig.updateAge;
+
 				/**
 				 * Calculate last updated date to throttle write updates to database
 				 * Formula: ({expiry date} - sessionMaxAge) + sessionUpdateAge
@@ -141,6 +142,7 @@ export const getSession = <Option extends BetterAuthOptions>() =>
 					session.session.expiresAt.valueOf() -
 					expiresIn * 1000 +
 					updateAge * 1000;
+
 				const shouldBeUpdated = sessionIsDueToBeUpdatedDate <= Date.now();
 
 				if (shouldBeUpdated) {

packages/better-auth/src/db/get-migration.ts

@@ -34,7 +34,7 @@ const mysqlMap = {
 		"float",
 		"double",
 	],
-	boolean: ["boolean"],
+	boolean: ["boolean", "tinyint"],
 	date: ["datetime", "date"],
 };
 

packages/better-auth/src/db/utils.ts

@@ -29,6 +29,7 @@ export async function getAdapter(options: BetterAuthOptions): Promise<Adapter> {
 			schema,
 			date: true,
 			boolean: databaseType === "sqlite",
+			databaseType,
 		},
 		generateId:
 			"generateId" in options.database

pnpm-lock.yaml

@@ -967,6 +967,9 @@ importers:
       mini-svg-data-uri:
         specifier: ^1.4.4
         version: 1.4.4
+      mysql2:
+        specifier: ^3.11.0
+        version: 3.11.3
       next:
         specifier: 15.0.0-canary.185
         version: 15.0.0-canary.185(@babel/core@7.26.0)(react-dom@19.0.0-rc-7771d3a7-20240827(react@19.0.0-rc-7771d3a7-20240827))(react@19.0.0-rc-7771d3a7-20240827)