feat: forward signIn auth params to /authorize (#1149)

* refactor: authorisation -> authorization

* feat: forward authorizationParams from signIn function

* refactor: take auth params as third argument

* docs: document signIn authorizationParams

src/client/index.js

@@ -234,7 +234,7 @@ const _useSessionHook = (session) => {
 }
 
 // Client side method
-export const signIn = async (provider, args = {}) => {
+export const signIn = async (provider, args = {}, authorizationParams = {}) => {
   const baseUrl = _apiBaseUrl()
   const callbackUrl = args.callbackUrl ?? window.location
   const providers = await getProviders()
@@ -257,6 +257,7 @@ export const signIn = async (provider, args = {}) => {
       },
       body: _encodedForm({
         ...args,
+        authorizationParams,
         csrfToken: await getCsrfToken(),
         callbackUrl: callbackUrl,
         json: true

src/server/lib/signin/oauth.js

@@ -2,23 +2,25 @@ import oAuthClient from '../oauth/client'
 import { createHash } from 'crypto'
 import logger from '../../../lib/logger'
 
-export default async function oauth (provider, csrfToken) {
-  const { callbackUrl } = provider
+export default async function getAuthorizationUrl (req) {
+  const { provider, csrfToken } = req.options
+
   const client = oAuthClient(provider)
   if (provider.version?.startsWith('2.')) {
     // Handle OAuth v2.x
     let url = client.getAuthorizeUrl({
-      redirect_uri: callbackUrl,
+      ...provider.authorizationParams,
+      ...req.body.authorizationParams,
+      redirect_uri: provider.callbackUrl,
       scope: provider.scope,
       // A hash of the NextAuth.js CSRF token is used as the state
-      state: createHash('sha256').update(csrfToken).digest('hex'),
-      ...provider.authorizationParams
+      state: createHash('sha256').update(csrfToken).digest('hex')
     })
 
     // If the authorizationUrl specified in the config has query parameters on it
     // make sure they are included in the URL we return.
     //
-    // This is a fix for an open issue with the oAuthClient library we are using
+    // This is a fix for an open issue with the OAuthClient library we are using
     // which inadvertantly strips them.
     //
     // https://github.com/ciaranj/node-oauth/pull/193
@@ -28,14 +30,17 @@ export default async function oauth (provider, csrfToken) {
       url = url.replace(baseUrl, provider.authorizationUrl + '&')
     }
 
+    logger.debug('GET_AUTHORIZATION_URL', url)
     return url
   }
 
   try {
-    const oAuthToken = await client.getOAuthRequestToken(callbackUrl)
-    return `${provider.authorizationUrl}?oauth_token=${oAuthToken}`
+    const oAuthToken = await client.getOAuthRequestToken(provider.callbackUrl)
+    const url = `${provider.authorizationUrl}?oauth_token=${oAuthToken}`
+    logger.debug('GET_AUTHORIZATION_URL', url)
+    return url
   } catch (error) {
-    logger.error('GET_AUTHORISATION_URL_ERROR', error)
+    logger.error('GET_AUTHORIZATION_URL_ERROR', error)
     throw error
   }
 }

src/server/routes/signin.js

@@ -1,4 +1,4 @@
-import oAuthSignin from '../lib/signin/oauth'
+import getAuthorizationUrl from '../lib/signin/oauth'
 import emailSignin from '../lib/signin/email'
 import logger from '../../lib/logger'
 
@@ -9,8 +9,7 @@ export default async function signin (req, res) {
     baseUrl,
     basePath,
     adapter,
-    callbacks,
-    csrfToken
+    callbacks
   } = req.options
 
   if (!provider.type) {
@@ -19,8 +18,8 @@ export default async function signin (req, res) {
 
   if (provider.type === 'oauth' && req.method === 'POST') {
     try {
-      const oAuthSigninUrl = await oAuthSignin(provider, csrfToken)
-      return res.redirect(oAuthSigninUrl)
+      const authorizazionUrl = await getAuthorizationUrl(req)
+      return res.redirect(authorizazionUrl)
     } catch (error) {
       logger.error('SIGNIN_OAUTH_ERROR', error)
       return res.redirect(`${baseUrl}${basePath}/error?error=OAuthSignin`)

www/docs/errors.md

@@ -45,7 +45,7 @@ These errors are displayed on the terminal.
 
 ### Signin / Callback
 
-#### GET_AUTHORISATION_URL_ERROR
+#### GET_AUTHORIZATION_URL_ERROR
 
 #### SIGNIN_OAUTH_ERROR
 

www/docs/getting-started/client.md

@@ -210,6 +210,25 @@ e.g.
 
 The URL must be considered valid by the [redirect callback handler](/configuration/callbacks#redirect). By default it requires the URL to be an absolute URL at the same hostname, or else it will redirect to the homepage. You can define your own redirect callback to allow other URLs, including supporting relative URLs.
 
+#### Additional params
+
+It is also possible to pass additional parameters to the `/authorize` endpoint through the third argument of `signIn()`.
+
+See the [Authorization Request OIDC spec](https://openid.net/specs/openid-connect-core-1_0.html#AuthRequest) for some ideas.
+
+e.g.
+
+* `signIn("identity-server4", null, { prompt: "login" })` *always ask the user to reauthenticate*
+* `signIn("auth0", null, { login_hint: "info@example.com" })` *hints the e-mail address to the provider*
+
+:::note
+You can also set these parameters through [`provider.authorizationParams`](/configuration/providers#oauth-provider-options).
+:::
+
+:::note
+The following parameters are always overridden: `redirect_uri`, `scope`, `state`
+:::
+
 ---
 
 ## signOut()