Add support for allowing users based on their domain (#1651)

e.g.
  ALLOWED_USER_DOMAINS=`["example.com"]`
  will allow both foo@example.com and bar@example.com

A user can log in if one of the conditions is true:
  - ALLOWED_USER_DOMAINS and ALLOWED_USER_EMAILS are empty
  - their email is in ALLOWED_USER_EMAILS
  - their email domain ALLOWED_USER_DOMAINS

Co-authored-by: Nathan Sarrazin <sarrazin.nathan@gmail.com>

.env

@@ -71,6 +71,8 @@ OPENID_CONFIG=
 MESSAGES_BEFORE_LOGIN=# how many messages a user can send in a conversation before having to login. set to 0 to force login right away
 # if it's defined, only these emails will be allowed to use login
 ALLOWED_USER_EMAILS=`[]` 
+# If it's defined, users with emails matching these domains will also be allowed to use login
+ALLOWED_USER_DOMAINS=`[]`
 # valid alternative redirect URLs for OAuth, used for HuggingChat apps
 ALTERNATIVE_REDIRECT_URLS=`[]` 
 ### Cookies

src/routes/login/callback/+page.server.ts

@@ -12,6 +12,12 @@ const allowedUserEmails = z
 	.default([])
 	.parse(JSON5.parse(env.ALLOWED_USER_EMAILS));
 
+const allowedUserDomains = z
+	.array(z.string().regex(/\.\w+$/)) // Contains at least a dot
+	.optional()
+	.default([])
+	.parse(JSON5.parse(env.ALLOWED_USER_DOMAINS));
+
 export async function load({ url, locals, cookies, request, getClientAddress }) {
 	const { error: errorName, error_description: errorDescription } = z
 		.object({
@@ -46,16 +52,21 @@ export async function load({ url, locals, cookies, request, getClientAddress })
 		iss
 	);
 
-	// Filter by allowed user emails
-	if (allowedUserEmails.length > 0) {
+	// Filter by allowed user emails or domains
+	if (allowedUserEmails.length > 0 || allowedUserDomains.length > 0) {
 		if (!userData.email) {
 			error(403, "User not allowed: email not returned");
 		}
 		const emailVerified = userData.email_verified ?? true;
 		if (!emailVerified) {
 			error(403, "User not allowed: email not verified");
 		}
-		if (!allowedUserEmails.includes(userData.email)) {
+
+		const emailDomain = userData.email.split("@")[1];
+		const isEmailAllowed = allowedUserEmails.includes(userData.email);
+		const isDomainAllowed = allowedUserDomains.includes(emailDomain);
+
+		if (!isEmailAllowed && !isDomainAllowed) {
 			error(403, "User not allowed");
 		}
 	}