feat: Add Line OAuth provider (#312)

Co-authored-by: wichai.damalee <renogies@gmail.com>
Co-authored-by: Sébastien Chopin <seb@nuxt.com>
Co-authored-by: Sébastien Chopin <atinux@gmail.com>

Author: 3 people

README.md

@@ -217,6 +217,7 @@ It can also be set using environment variables:
 - Hubspot
 - Instagram
 - Keycloak
+- Line
 - Linear
 - LinkedIn
 - Microsoft

playground/.env.example

@@ -100,4 +100,8 @@ NUXT_OAUTH_STRAVA_CLIENT_SECRET=
 # Hubspot
 NUXT_OAUTH_HUBSPOT_CLIENT_ID=
 NUXT_OAUTH_HUBSPOT_CLIENT_SECRET=
-NUXT_OAUTH_HUBSPOT_REDIRECT_URL=
+NUXT_OAUTH_HUBSPOT_REDIRECT_URL=
+# Line
+NUXT_OAUTH_LINE_CLIENT_ID=
+NUXT_OAUTH_LINE_CLIENT_SECRET=
+NUXT_OAUTH_LINE_REDIRECT_URL=

playground/app.vue

@@ -33,6 +33,12 @@ const providers = computed(() =>
       disabled: Boolean(user.value?.gitlab),
       icon: 'i-simple-icons-gitlab',
     },
+    {
+      label: user.value?.line || 'Line',
+      to: '/auth/line',
+      disabled: Boolean(user.value?.line),
+      icon: 'i-simple-icons-line',
+    },
     {
       label: user.value?.linear || 'Linear',
       to: '/auth/linear',

playground/auth.d.ts

@@ -13,6 +13,7 @@ declare module '#auth-utils' {
     discord?: string
     battledotnet?: string
     keycloak?: string
+    line?: string
     linear?: string
     linkedin?: string
     cognito?: string

playground/server/routes/auth/line.get.ts

@@ -0,0 +1,12 @@
+export default defineOAuthLineEventHandler({
+  async onSuccess(event, { user }) {
+    await setUserSession(event, {
+      user: {
+        line: user.userId,
+      },
+      loggedInAt: Date.now(),
+    });
+
+    return sendRedirect(event, '/');
+  },
+});

src/module.ts

@@ -355,5 +355,11 @@ export default defineNuxtModule<ModuleOptions>({
       clientSecret: '',
       redirectURL: '',
     })
+    // Line OAuth
+    runtimeConfig.oauth.line = defu(runtimeConfig.oauth.line, {
+      clientId: '',
+      clientSecret: '',
+      redirectURL: '',
+    })
   },
 })

src/runtime/server/lib/oauth/line.ts

@@ -0,0 +1,139 @@
+import type { H3Event } from 'h3'
+import { eventHandler, getQuery, sendRedirect, createError } from 'h3'
+import { withQuery } from 'ufo'
+import { defu } from 'defu'
+import { handleMissingConfiguration, handleAccessTokenErrorResponse, getOAuthRedirectURL, requestAccessToken } from '../utils'
+import { useRuntimeConfig } from '#imports'
+import type { OAuthConfig } from '#auth-utils'
+
+export interface OAuthLineConfig {
+  /**
+   * Line OAuth Client ID
+   * @default process.env.NUXT_OAUTH_LINE_CLIENT_ID
+   */
+  clientId?: string
+
+  /**
+   * Line OAuth Client Secret
+   * @default process.env.NUXT_OAUTH_LINE_CLIENT_SECRET
+   */
+  clientSecret?: string
+
+  /**
+   * Line OAuth Scope
+   * @default ['profile', 'openid']
+   * @see https://developers.line.biz/en/docs/line-login/integrate-line-login/
+   */
+  scope?: string[]
+
+  /**
+   * Line OAuth Authorization URL
+   * @default 'https://access.line.me/oauth2/v2.1/authorize'
+   */
+  authorizationURL?: string
+
+  /**
+   * Line OAuth Token URL
+   * @default 'https://api.line.me/oauth2/v2.1/token'
+   */
+  tokenURL?: string
+
+  /**
+   * Line OAuth User Info URL
+   * @default 'https://api.line.me/v2/profile'
+   */
+  userURL?: string
+
+  /**
+   * Extra authorization parameters to provide to the authorization URL
+   * @example { bot_prompt: 'normal' }
+   */
+  authorizationParams?: Record<string, string>
+
+  /**
+   * Redirect URL to to allow overriding for situations like prod failing to determine public hostname
+   * @default process.env.NUXT_OAUTH_LINE_REDIRECT_URL or current URL
+   */
+  redirectURL?: string
+}
+
+export function defineOAuthLineEventHandler({
+  config,
+  onSuccess,
+  onError,
+}: OAuthConfig<OAuthLineConfig>) {
+  return eventHandler(async (event: H3Event) => {
+    config = defu(config, useRuntimeConfig(event).oauth?.line, {
+      authorizationURL: 'https://access.line.me/oauth2/v2.1/authorize',
+      tokenURL: 'https://api.line.me/oauth2/v2.1/token',
+      userURL: 'https://api.line.me/v2/profile',
+      authorizationParams: {},
+    }) as OAuthLineConfig
+
+    const query = getQuery<{ code?: string, error?: string, state?: string }>(event)
+
+    if (query.error) {
+      return onError(
+        event,
+        new Error(`Line login failed: ${query.error || 'Unknown error'}`),
+      )
+    }
+
+    if (!config.clientId || !config.clientSecret) {
+      return handleMissingConfiguration(event, 'line', ['clientId', 'clientSecret'], onError)
+    }
+
+    const redirectURL = config.redirectURL || getOAuthRedirectURL(event)
+    if (!query.code) {
+      config.scope = config.scope || ['profile', 'openid']
+      // Redirect to Line OAuth page
+      return sendRedirect(
+        event,
+        withQuery(config.authorizationURL as string, {
+          response_type: 'code',
+          client_id: config.clientId,
+          redirect_uri: redirectURL,
+          scope: config.scope.join(' '),
+          state: query.state || '',
+          ...config.authorizationParams,
+        }),
+      )
+    }
+
+    const tokens = await requestAccessToken(config.tokenURL as string, {
+      body: {
+        grant_type: 'authorization_code',
+        code: query.code as string,
+        client_id: config.clientId,
+        client_secret: config.clientSecret,
+        redirect_uri: redirectURL,
+      },
+    })
+
+    if (tokens.error) {
+      return handleAccessTokenErrorResponse(event, 'line', tokens, onError)
+    }
+
+    const accessToken = tokens.access_token
+    const user = await $fetch(config.userURL as string, {
+      headers: {
+        Authorization: `Bearer ${accessToken}`,
+      },
+    })
+
+    if (!user) {
+      const error = createError({
+        statusCode: 500,
+        message: 'Could not get Line user',
+        data: tokens,
+      })
+      if (!onError) throw error
+      return onError(event, error)
+    }
+
+    return onSuccess(event, {
+      tokens,
+      user,
+    })
+  })
+}

src/runtime/types/oauth-config.ts

@@ -1,6 +1,6 @@
 import type { H3Event, H3Error } from 'h3'
 
-export type OAuthProvider = 'auth0' | 'authentik' | 'battledotnet' | 'cognito' | 'discord' | 'dropbox' | 'facebook' | 'github' | 'gitlab' | 'google' | 'hubspot' | 'instagram' | 'keycloak' | 'linear' | 'linkedin' | 'microsoft' | 'paypal' | 'polar' | 'spotify' | 'seznam' | 'steam' | 'strava' | 'tiktok' | 'twitch' | 'vk' | 'workos' | 'x' | 'xsuaa' | 'yandex' | 'zitadel' | (string & {})
+export type OAuthProvider = 'auth0' | 'authentik' | 'battledotnet' | 'cognito' | 'discord' | 'dropbox' | 'facebook' | 'github' | 'gitlab' | 'google' | 'hubspot' | 'instagram' | 'keycloak' | 'line' | 'linear' | 'linkedin' | 'microsoft' | 'paypal' | 'polar' | 'spotify' | 'seznam' | 'steam' | 'strava' | 'tiktok' | 'twitch' | 'vk' | 'workos' | 'x' | 'xsuaa' | 'yandex' | 'zitadel' | (string & {})
 
 export type OnError = (event: H3Event, error: H3Error) => Promise<void> | void