Line

OAuth 2.0 provider for Line.

Also see the OAuth 2.0 guide.

Initialization

import { Line } from "arctic";

const line = new Line(clientId, clientSecret, redirectURI);

Create authorization URL

import { generateState, generateCodeVerifier } from "arctic";

const state = generateState();
const codeVerifier = generateCodeVerifier();
const scopes = ["openid", "profile"];
const url = line.createAuthorizationURL(state, codeVerifier, scopes);

Validate authorization code

validateAuthorizationCode() will either return an OAuth2Tokens, or throw one of OAuth2RequestError, ArcticFetchError, or a standard Error (parse errors). Line returns an access token, the access token expiration, and a refresh token.

import { OAuth2RequestError, ArcticFetchError } from "arctic";

try {
	const tokens = await line.validateAuthorizationCode(code, codeVerifier);
	const accessToken = tokens.accessToken();
	const accessTokenExpiresAt = tokens.accessTokenExpiresAt();
	const refreshToken = tokens.refreshToken();
} catch (e) {
	if (e instanceof OAuth2RequestError) {
		// Invalid authorization code, credentials, or redirect URI
		const code = e.code;
		// ...
	}
	if (e instanceof ArcticFetchError) {
		// Failed to call `fetch()`
		const cause = e.cause;
		// ...
	}
	// Parse error
}

Refresh access tokens

Use refreshAccessToken() to get a new access token using a refresh token. Line only returns a new access token and its expiration. This method also returns OAuth2Tokens and throws the same errors as validateAuthorizationCode()

import { OAuth2RequestError, ArcticFetchError } from "arctic";

try {
	const tokens = await line.refreshAccessToken(accessToken);
	const accessToken = tokens.accessToken();
	const accessTokenExpiresAt = tokens.accessTokenExpiresAt();
} catch (e) {
	if (e instanceof OAuth2RequestError) {
		// Invalid authorization code, credentials, or redirect URI
	}
	if (e instanceof ArcticFetchError) {
		// Failed to call `fetch()`
	}
	// Parse error
}

OpenID Connect

Use OpenID Connect with the openid scope to get the user's profile with an ID token or the userinfo endpoint. Arctic provides decodeIdToken() for decoding the token's payload.

const scopes = ["openid"];
const url = line.createAuthorizationURL(state, codeVerifier, scopes);

import { decodeIdToken } from "arctic";

const tokens = await line.validateAuthorizationCode(code, codeVerifier);
const idToken = tokens.idToken();
const claims = decodeIdToken(idToken);

const response = await fetch("https://api.line.me/oauth2/v2.1/userinfo", {
	headers: {
		Authorization: `Bearer ${accessToken}`
	}
});
const user = await response.json();

Get user profile

Make sure to add the profile scope to get the user profile and the email scope to get the user email.

const scopes = ["openid", "profile", "email"];
const url = line.createAuthorizationURL(state, codeVerifier, scopes);

Or, alternatively use the /profile endpoint.