feat: add system configuration API endpoint and frontend hook for dynamic settings

k-notes-frontend/src/hooks/useConfig.ts

@@ -0,0 +1,15 @@
+
+import { useQuery } from "@tanstack/react-query";
+import { api } from "@/lib/api";
+
+export interface ConfigResponse {
+    allow_registration: boolean;
+}
+
+export function useConfig() {
+    return useQuery<ConfigResponse>({
+        queryKey: ["config"],
+        queryFn: () => api.get("/config"),
+        staleTime: Infinity, // Config rarely changes
+    });
+}

k-notes-frontend/src/pages/login.tsx

@@ -6,6 +6,7 @@ import { zodResolver } from "@hookform/resolvers/zod";
 import { z } from "zod";
 import { Link } from "react-router-dom";
 import { useLogin } from "@/hooks/use-auth";
+import { useConfig } from "@/hooks/useConfig";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/components/ui/card";
@@ -22,6 +23,7 @@ type LoginFormValues = z.infer<typeof loginSchema>;
 
 export default function LoginPage() {
   const { mutate: login, isPending } = useLogin();
+  const { data: config } = useConfig();
 
   const form = useForm<LoginFormValues>({
     resolver: zodResolver(loginSchema),
@@ -95,12 +97,14 @@ export default function LoginPage() {
           </Form>
         </CardContent>
         <CardFooter className="flex justify-center">
+          {config?.allow_registration !== false && (
             <p className="text-sm text-gray-500 dark:text-gray-400">
               Don't have an account?{" "}
               <Link to="/register" className="font-semibold text-primary hover:underline">
                 Sign up
               </Link>
             </p>
+          )}
         </CardFooter>
       </Card>
       <SettingsDialog open={settingsOpen} onOpenChange={setSettingsOpen} dataManagementEnabled={false} />

k-notes-frontend/src/pages/register.tsx

@@ -1,11 +1,12 @@
-import { useState } from "react";
+import { useState, useEffect } from "react";
 import { useForm } from "react-hook-form";
 import { Settings } from "lucide-react";
 import { SettingsDialog } from "@/components/settings-dialog";
 import { zodResolver } from "@hookform/resolvers/zod";
 import { z } from "zod";
-import { Link } from "react-router-dom";
+import { Link, useNavigate } from "react-router-dom";
 import { useRegister } from "@/hooks/use-auth";
+import { useConfig } from "@/hooks/useConfig";
 import { Button } from "@/components/ui/button";
 import { Input } from "@/components/ui/input";
 import { Card, CardContent, CardDescription, CardFooter, CardHeader, CardTitle } from "@/components/ui/card";
@@ -26,6 +27,19 @@ type RegisterFormValues = z.infer<typeof registerSchema>;
 
 export default function RegisterPage() {
   const { mutate: register, isPending } = useRegister();
+  const { data: config, isLoading: isConfigLoading } = useConfig();
+  const navigate = useNavigate();
+
+  useEffect(() => {
+    if (!isConfigLoading && config?.allow_registration === false) {
+      toast.error("Registration is currently disabled");
+      navigate("/login");
+    }
+  }, [config, isConfigLoading, navigate]);
+
+  if (isConfigLoading || config?.allow_registration === false) {
+    return null; // Or a loading spinner
+  }
 
   const form = useForm<RegisterFormValues>({
     resolver: zodResolver(registerSchema),

notes-api/src/dto.rs

@@ -166,3 +166,9 @@ impl From<notes_domain::NoteVersion> for NoteVersionResponse {
         }
     }
 }
+
+/// System configuration response
+#[derive(Debug, Serialize)]
+pub struct ConfigResponse {
+    pub allow_registration: bool,
+}

notes-api/src/routes/config.rs

@@ -0,0 +1,14 @@
+//! Configuration routes
+
+use axum::{Json, extract::State};
+
+use crate::dto::ConfigResponse;
+use crate::error::ApiResult;
+use crate::state::AppState;
+
+/// Get system configuration
+pub async fn get_config(State(state): State<AppState>) -> ApiResult<Json<ConfigResponse>> {
+    Ok(Json(ConfigResponse {
+        allow_registration: state.config.allow_registration,
+    }))
+}

notes-api/src/routes/mod.rs

@@ -1,6 +1,7 @@
 //! Route definitions and module structure
 
 pub mod auth;
+pub mod config;
 pub mod import_export;
 pub mod notes;
 pub mod tags;
@@ -40,4 +41,6 @@ pub fn api_v1_router() -> Router<AppState> {
             "/tags/{id}",
             delete(tags::delete_tag).patch(tags::rename_tag),
         )
+        // System Config
+        .route("/config", get(config::get_config))
 }