LINE
Get your LINE credentials
- Create a channel in the LINE Developers Console.
- Note your Channel ID (client_id) and Channel secret (client_secret).
- In the channel settings, add your Redirect URI, e.g.
http://localhost:3000/api/auth/callback/linefor local development. - Enable required scopes (at least
openid; addprofile,emailif you need name, avatar, email).
See LINE Login v2.1 reference for details: [https://developers.line.biz/en/reference/line-login/#issue-access-token]
Configure the provider
Add your LINE credentials to socialProviders.line in your auth configuration.
import { betterAuth } from "better-auth";
export const auth = betterAuth({
socialProviders: {
line: {
clientId: process.env.LINE_CLIENT_ID as string,
clientSecret: process.env.LINE_CLIENT_SECRET as string,
// Optional: override redirect if needed
// redirectURI: "https://your.app/api/auth/callback/line",
// scopes are prefilled: ["openid","profile","email"]. Append if needed
},
},
});Usage
Sign In with LINE
Use the client signIn.social with provider: "line".
import { createAuthClient } from "better-auth/client";
const authClient = createAuthClient();
async function signInWithLINE() {
const res = await authClient.signIn.social({ provider: "line" });
}Sign In with LINE using ID Token (optional)
If you obtain the LINE ID token on the client, you can sign in directly without redirection.
await authClient.signIn.social({
provider: "line",
idToken: {
token: "<LINE_ID_TOKEN>",
accessToken: "<LINE_ACCESS_TOKEN>",
},
});Notes
- Default scopes include
openid profile email. Adjust as needed via provider options. - Verify redirect URI exactly matches the value configured in LINE Developers Console.
- LINE ID token verification uses the official endpoint and checks audience and optional nonce per spec.
Designing a login button? Follow LINE's button guidelines.