fix(auth): migrate from next-auth to better-auth (#1453)

app/(auth)/actions.ts

@@ -1,10 +1,7 @@
 "use server";
 
 import { z } from "zod";
-
-import { createUser, getUser } from "@/lib/db/queries";
-
-import { signIn } from "./auth";
+import { auth } from "@/lib/auth";
 
 const authFormSchema = z.object({
   email: z.string().email(),
@@ -25,10 +22,11 @@ export const login = async (
       password: formData.get("password"),
     });
 
-    await signIn("credentials", {
-      email: validatedData.email,
-      password: validatedData.password,
-      redirect: false,
+    await auth.api.signInEmail({
+      body: {
+        email: validatedData.email,
+        password: validatedData.password,
+      },
     });
 
     return { status: "success" };
@@ -61,24 +59,29 @@ export const register = async (
       password: formData.get("password"),
     });
 
-    const [user] = await getUser(validatedData.email);
-
-    if (user) {
-      return { status: "user_exists" } as RegisterActionState;
-    }
-    await createUser(validatedData.email, validatedData.password);
-    await signIn("credentials", {
-      email: validatedData.email,
-      password: validatedData.password,
-      redirect: false,
+    const result = await auth.api.signUpEmail({
+      body: {
+        email: validatedData.email,
+        password: validatedData.password,
+        name: validatedData.email,
+      },
     });
 
+    if (!result) {
+      return { status: "failed" };
+    }
+
     return { status: "success" };
   } catch (error) {
     if (error instanceof z.ZodError) {
       return { status: "invalid_data" };
     }
 
+    const message = error instanceof Error ? error.message : "";
+    if (message.includes("already exists") || message.includes("UNIQUE")) {
+      return { status: "user_exists" };
+    }
+
     return { status: "failed" };
   }
 };

app/(auth)/api/auth/[...nextauth]/route.ts

@@ -1 +0,0 @@
-export { GET, POST } from "@/app/(auth)/auth";

app/(auth)/api/auth/guest/route.ts

@@ -1,21 +0,0 @@
-import { NextResponse } from "next/server";
-import { getToken } from "next-auth/jwt";
-import { signIn } from "@/app/(auth)/auth";
-import { isDevelopmentEnvironment } from "@/lib/constants";
-
-export async function GET(request: Request) {
-  const { searchParams } = new URL(request.url);
-  const redirectUrl = searchParams.get("redirectUrl") || "/";
-
-  const token = await getToken({
-    req: request,
-    secret: process.env.AUTH_SECRET,
-    secureCookie: !isDevelopmentEnvironment,
-  });
-
-  if (token) {
-    return NextResponse.redirect(new URL("/", request.url));
-  }
-
-  return signIn("guest", { redirect: true, redirectTo: redirectUrl });
-}

app/(auth)/auth.config.ts

@@ -1,14 +0,0 @@
-import type { NextAuthConfig } from "next-auth";
-
-export const authConfig = {
-  basePath: "/api/auth",
-  pages: {
-    signIn: "/login",
-    newUser: "/",
-  },
-  providers: [
-    // added later in auth.ts since it requires bcrypt which is only compatible with Node.js
-    // while this file is also used in non-Node.js environments
-  ],
-  callbacks: {},
-} satisfies NextAuthConfig;

app/(auth)/auth.ts

@@ -1,94 +0,0 @@
-import { compare } from "bcrypt-ts";
-import NextAuth, { type DefaultSession } from "next-auth";
-import type { DefaultJWT } from "next-auth/jwt";
-import Credentials from "next-auth/providers/credentials";
-import { DUMMY_PASSWORD } from "@/lib/constants";
-import { createGuestUser, getUser } from "@/lib/db/queries";
-import { authConfig } from "./auth.config";
-
-export type UserType = "guest" | "regular";
-
-declare module "next-auth" {
-  interface Session extends DefaultSession {
-    user: {
-      id: string;
-      type: UserType;
-    } & DefaultSession["user"];
-  }
-
-  interface User {
-    id?: string;
-    email?: string | null;
-    type: UserType;
-  }
-}
-
-declare module "next-auth/jwt" {
-  interface JWT extends DefaultJWT {
-    id: string;
-    type: UserType;
-  }
-}
-
-export const {
-  handlers: { GET, POST },
-  auth,
-  signIn,
-  signOut,
-} = NextAuth({
-  ...authConfig,
-  providers: [
-    Credentials({
-      credentials: {},
-      async authorize({ email, password }: any) {
-        const users = await getUser(email);
-
-        if (users.length === 0) {
-          await compare(password, DUMMY_PASSWORD);
-          return null;
-        }
-
-        const [user] = users;
-
-        if (!user.password) {
-          await compare(password, DUMMY_PASSWORD);
-          return null;
-        }
-
-        const passwordsMatch = await compare(password, user.password);
-
-        if (!passwordsMatch) {
-          return null;
-        }
-
-        return { ...user, type: "regular" };
-      },
-    }),
-    Credentials({
-      id: "guest",
-      credentials: {},
-      async authorize() {
-        const [guestUser] = await createGuestUser();
-        return { ...guestUser, type: "guest" };
-      },
-    }),
-  ],
-  callbacks: {
-    jwt({ token, user }) {
-      if (user) {
-        token.id = user.id as string;
-        token.type = user.type;
-      }
-
-      return token;
-    },
-    session({ session, token }) {
-      if (session.user) {
-        session.user.id = token.id;
-        session.user.type = token.type;
-      }
-
-      return session;
-    },
-  },
-});

app/(auth)/login/page.tsx

@@ -2,12 +2,12 @@
 
 import Link from "next/link";
 import { useRouter } from "next/navigation";
-import { useSession } from "next-auth/react";
 import { useActionState, useEffect, useState } from "react";
 
 import { AuthForm } from "@/components/auth-form";
 import { SubmitButton } from "@/components/submit-button";
 import { toast } from "@/components/toast";
+import { useSession } from "@/lib/client";
 import { type LoginActionState, login } from "../actions";
 
 export default function Page() {
@@ -23,9 +23,9 @@ export default function Page() {
     }
   );
 
-  const { update: updateSession } = useSession();
+  const { refetch } = useSession();
 
-  // biome-ignore lint/correctness/useExhaustiveDependencies: router and updateSession are stable refs
+  // biome-ignore lint/correctness/useExhaustiveDependencies: router and refetch are stable refs
   useEffect(() => {
     if (state.status === "failed") {
       toast({
@@ -39,7 +39,7 @@ export default function Page() {
       });
     } else if (state.status === "success") {
       setIsSuccessful(true);
-      updateSession();
+      refetch();
       router.refresh();
     }
   }, [state.status]);

app/(auth)/register/page.tsx

@@ -2,11 +2,11 @@
 
 import Link from "next/link";
 import { useRouter } from "next/navigation";
-import { useSession } from "next-auth/react";
 import { useActionState, useEffect, useState } from "react";
 import { AuthForm } from "@/components/auth-form";
 import { SubmitButton } from "@/components/submit-button";
 import { toast } from "@/components/toast";
+import { useSession } from "@/lib/client";
 import { type RegisterActionState, register } from "../actions";
 
 export default function Page() {
@@ -22,9 +22,9 @@ export default function Page() {
     }
   );
 
-  const { update: updateSession } = useSession();
+  const { refetch } = useSession();
 
-  // biome-ignore lint/correctness/useExhaustiveDependencies: router and updateSession are stable refs
+  // biome-ignore lint/correctness/useExhaustiveDependencies: router and refetch are stable refs
   useEffect(() => {
     if (state.status === "user_exists") {
       toast({ type: "error", description: "Account already exists!" });
@@ -39,7 +39,7 @@ export default function Page() {
       toast({ type: "success", description: "Account created successfully!" });
 
       setIsSuccessful(true);
-      updateSession();
+      refetch();
       router.refresh();
     }
   }, [state.status]);