Initial fullstack project setup with Next.js 15, Gin, PostgreSQL and Docker Compose

- Frontend: Next.js 15 (App Router), Auth.js v5, shadcn/ui, MagicUI
- Backend: Go + Gin + GORM with layered architecture
- Auth: Local credentials login with optional Keycloak OAuth binding
- Admin: RBAC user management for admin role
- Dev: Docker Compose with hot reload for both frontend and backend
- Docker: 3-service orchestration (frontend, backend, postgres)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/app/login/login-form.tsx

@@ -0,0 +1,101 @@
+"use client";
+
+import { useState } from "react";
+import { signIn } from "next-auth/react";
+import { useSearchParams } from "next/navigation";
+import { Button } from "@/components/ui/button";
+import { Input } from "@/components/ui/input";
+import { Label } from "@/components/ui/label";
+import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
+
+export function LoginForm({ hasKeycloak }: { hasKeycloak: boolean }) {
+  const searchParams = useSearchParams();
+  const callbackUrl = searchParams.get("callbackUrl") || "/dashboard";
+  const [username, setUsername] = useState("");
+  const [password, setPassword] = useState("");
+  const [error, setError] = useState("");
+
+  async function handleSubmit(e: React.FormEvent) {
+    e.preventDefault();
+    setError("");
+
+    const res = await signIn("credentials", {
+      username,
+      password,
+      redirect: false,
+      callbackUrl,
+    });
+
+    if (res?.error) {
+      setError("登录失败，请检查用户名和密码");
+    } else {
+      const redirectUrl = callbackUrl.startsWith("http")
+        ? callbackUrl
+        : window.location.origin + callbackUrl;
+      window.location.href = redirectUrl;
+    }
+  }
+
+  return (
+    <Card className="w-full max-w-md">
+      <CardHeader>
+        <CardTitle className="text-center">登录</CardTitle>
+      </CardHeader>
+      <CardContent className="space-y-4">
+        <form onSubmit={handleSubmit} className="space-y-4">
+          <div>
+            <Label htmlFor="username">用户名</Label>
+            <Input
+              id="username"
+              value={username}
+              onChange={(e) => setUsername(e.target.value)}
+              required
+            />
+          </div>
+          <div>
+            <Label htmlFor="password">密码</Label>
+            <Input
+              id="password"
+              type="password"
+              value={password}
+              onChange={(e) => setPassword(e.target.value)}
+              required
+            />
+          </div>
+          {error && <p className="text-sm text-red-500">{error}</p>}
+          <Button type="submit" className="w-full">
+            本地账号登录
+          </Button>
+        </form>
+
+        {hasKeycloak && (
+          <>
+            <div className="relative">
+              <div className="absolute inset-0 flex items-center">
+                <span className="w-full border-t" />
+              </div>
+              <div className="relative flex justify-center text-xs uppercase">
+                <span className="bg-white px-2 text-gray-500">或者</span>
+              </div>
+            </div>
+
+            <Button
+              variant="outline"
+              className="w-full"
+              onClick={() => signIn("keycloak", { callbackUrl })}
+            >
+              Keycloak 登录
+            </Button>
+          </>
+        )}
+
+        <p className="text-center text-sm text-gray-500">
+          还没有账号？{" "}
+          <a href="/register" className="text-blue-600 hover:underline">
+            立即注册
+          </a>
+        </p>
+      </CardContent>
+    </Card>
+  );
+}