Add admin login page for web UI

server/auth.py

@@ -19,7 +19,7 @@ from typing import Optional
 
 from jose import JWTError, jwt
 from passlib.context import CryptContext
-from fastapi import Depends, HTTPException, status
+from fastapi import Depends, HTTPException, Request, status
 from fastapi.security import OAuth2PasswordBearer
 from sqlalchemy.orm import Session
 
@@ -36,7 +36,7 @@ ACCESS_TOKEN_EXPIRE_MINUTES = int(os.getenv("ACCESS_TOKEN_EXPIRE_MINUTES", "60")
 # Password hashing context
 pwd_context = CryptContext(schemes=["bcrypt"], deprecated="auto")
 
-oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/login")
+oauth2_scheme = OAuth2PasswordBearer(tokenUrl="/api/login", auto_error=False)
 
 
 def hash_password(password: str) -> str:
@@ -58,7 +58,9 @@ def create_access_token(data: dict, expires_delta: Optional[datetime.timedelta]
 
 
 async def get_current_user(
-    token: str = Depends(oauth2_scheme), db: Session = Depends(get_db)
+    request: Request,
+    token: str | None = Depends(oauth2_scheme),
+    db: Session = Depends(get_db),
 ) -> models.User:
     """Retrieve the current user from a JWT token."""
     credentials_exception = HTTPException(
@@ -66,8 +68,11 @@ async def get_current_user(
         detail="Could not validate credentials",
         headers={"WWW-Authenticate": "Bearer"},
     )
+    raw_token = token or request.cookies.get("access_token")
+    if not raw_token:
+        raise credentials_exception
     try:
-        payload = jwt.decode(token, SECRET_KEY, algorithms=[ALGORITHM])
+        payload = jwt.decode(raw_token, SECRET_KEY, algorithms=[ALGORITHM])
         user_id: int | None = payload.get("sub")
         if user_id is None:
             raise credentials_exception

server/main.py

@@ -37,9 +37,10 @@ from fastapi import (
     Request,
     Response,
 )
-from fastapi.responses import HTMLResponse, FileResponse
+from fastapi.responses import HTMLResponse, FileResponse, RedirectResponse
 from fastapi.templating import Jinja2Templates
 from fastapi.security import OAuth2PasswordRequestForm
+from fastapi.exception_handlers import http_exception_handler
 from sqlalchemy.orm import Session
 
 from . import models, schemas, auth, storage as storage_module, database
@@ -50,6 +51,17 @@ templates = Jinja2Templates(directory=os.path.join(os.path.dirname(__file__), "t
 storage = storage_module.get_storage()
 
 
+@app.exception_handler(HTTPException)
+async def custom_http_exception_handler(request: Request, exc: HTTPException) -> Response:
+    if (
+        exc.status_code == status.HTTP_401_UNAUTHORIZED
+        and "text/html" in request.headers.get("accept", "")
+        and not request.url.path.startswith("/api")
+    ):
+        return RedirectResponse(url="/login")
+    return await http_exception_handler(request, exc)
+
+
 @app.on_event("startup")
 async def on_startup() -> None:
     # Create database tables if they do not exist
@@ -649,6 +661,53 @@ async def update_client_config(
 
 # ======== Web interface routes =========
 
+@app.get("/login", response_class=HTMLResponse)
+async def login_page(request: Request) -> Response:
+    return templates.TemplateResponse(
+        "login.html",
+        {
+            "request": request,
+            "title": "Admin Login",
+        },
+    )
+
+
+@app.post("/login", response_class=HTMLResponse)
+async def login_submit(
+    request: Request,
+    username: str = Form(...),
+    password: str = Form(...),
+    db: Session = Depends(database.get_db),
+) -> Response:
+    user = db.query(models.User).filter(models.User.username == username).first()
+    if not user or not auth.verify_password(password, user.hashed_password):
+        return templates.TemplateResponse(
+            "login.html",
+            {
+                "request": request,
+                "title": "Admin Login",
+                "error": "Invalid username or password.",
+            },
+            status_code=status.HTTP_401_UNAUTHORIZED,
+        )
+    access_token = auth.create_access_token(data={"sub": user.id, "is_admin": user.is_admin})
+    response = RedirectResponse(url="/clients", status_code=status.HTTP_303_SEE_OTHER)
+    response.set_cookie(
+        "access_token",
+        access_token,
+        httponly=True,
+        samesite="lax",
+    )
+    return response
+
+
+@app.get("/logout")
+async def logout() -> Response:
+    response = RedirectResponse(url="/login", status_code=status.HTTP_303_SEE_OTHER)
+    response.delete_cookie("access_token")
+    return response
+
+
 @app.get("/clients", response_class=HTMLResponse)
 async def list_clients_page(
     request: Request,

server/templates/base.html

@@ -12,6 +12,13 @@
         <nav class="container mx-auto px-4 py-3 flex items-center space-x-4">
             <a href="/" class="text-xl font-semibold">Backup Service</a>
             <a href="/clients" class="hover:underline">Clients</a>
+            <div class="ml-auto">
+                {% if user %}
+                    <a href="/logout" class="hover:underline">Logout</a>
+                {% else %}
+                    <a href="/login" class="hover:underline">Login</a>
+                {% endif %}
+            </div>
         </nav>
     </header>
     <main class="container mx-auto p-4">

server/templates/login.html

@@ -0,0 +1,23 @@
+{% extends "base.html" %}
+{% block content %}
+<div class="max-w-md mx-auto bg-white shadow rounded-lg p-6 mt-8">
+    <h1 class="text-2xl font-bold mb-2">Admin Login</h1>
+    <p class="text-sm text-gray-600 mb-6">Sign in to manage clients and backups.</p>
+    {% if error %}
+        <div class="mb-4 rounded border border-red-200 bg-red-50 px-3 py-2 text-sm text-red-700">
+            {{ error }}
+        </div>
+    {% endif %}
+    <form action="/login" method="post" class="space-y-4">
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1" for="username">Username</label>
+            <input id="username" type="text" name="username" required class="shadow-sm focus:ring-blue-500 focus:border-blue-500 block w-full sm:text-sm border-gray-300 rounded-md p-2" />
+        </div>
+        <div>
+            <label class="block text-sm font-medium text-gray-700 mb-1" for="password">Password</label>
+            <input id="password" type="password" name="password" required class="shadow-sm focus:ring-blue-500 focus:border-blue-500 block w-full sm:text-sm border-gray-300 rounded-md p-2" />
+        </div>
+        <button type="submit" class="inline-flex items-center px-4 py-2 border border-transparent text-sm font-medium rounded-md shadow-sm text-white bg-blue-600 hover:bg-blue-700 focus:outline-none focus:ring-2 focus:ring-offset-2 focus:ring-blue-500">Sign In</button>
+    </form>
+</div>
+{% endblock %}