メニュー
Modern React framework for building full-stack web applications with App Router, Server Components, and optimized performance
Database migration management for SQLAlchemy projects using Alembic
Advanced Python Scheduler - Task scheduling and job queue system
Build async APIs with FastAPI, including endpoints, dependency injection, validation, and testing. Use when creating REST APIs, web backends, or microservices.
Data validation and settings management using Python type annotations with Pydantic v2
Structured logging for Python applications with context support and powerful processors
ASGI server for Python web applications - Fast, production-ready server for async frameworks
| name | Next.js 15 |
| description | Modern React framework for building full-stack web applications with App Router, Server Components, and optimized performance |
| when_to_use | Building React applications with server-side rendering, static site generation, API routes, or full-stack applications |
Next.js is a React framework that provides server-side rendering, static site generation, API routes, and many other features for building modern web applications.
npx create-next-app@latest my-app
cd my-app
npm run dev
Server Components (default):
// app/page.tsx
async function getPosts() {
const res = await fetch("https://api.example.com/posts");
return res.json();
}
export default async function Page() {
const posts = await getPosts();
return <PostList posts={posts} />;
}
Client Components (with 'use client'):
// components/Counter.tsx
"use client";
import { useState } from "react";
export default function Counter() {
const [count, setCount] = useState(0);
return <button onClick={() => setCount(count + 1)}>Count: {count}</button>;
}
Static Data (Default):
// Cached until manually invalidated
export default async function Page() {
const data = await fetch("https://api.example.com/posts");
return <PostsList posts={await data.json()} />;
}
Dynamic Data (No Cache):
// Refetched on every request
export default async function Page() {
const data = await fetch("https://api.example.com/posts", {
cache: "no-store",
});
return <PostsList posts={await data.json()} />;
}
Revalidated Data:
// Revalidated every 60 seconds
export default async function Page() {
const data = await fetch("https://api.example.com/posts", {
next: { revalidate: 60 },
});
return <PostsList posts={await data.json()} />;
}
Create API endpoints in the app directory:
// app/api/posts/route.ts
import { NextResponse } from "next/server";
export async function GET() {
const res = await fetch("https://api.example.com/posts");
const posts = await res.json();
return NextResponse.json(posts);
}
export async function POST(request: Request) {
const body = await request.json();
// Create post logic
return NextResponse.json({ success: true });
}
Root Layout:
// app/layout.tsx
export default function RootLayout({
children,
}: {
children: React.ReactNode;
}) {
return (
<html lang="en">
<body>
<Header />
<main>{children}</main>
<Footer />
</body>
</html>
);
}
Dynamic Routes:
// app/blog/[slug]/page.tsx
export default async function BlogPost({
params,
}: {
params: Promise<{ slug: string }>;
}) {
const { slug } = await params;
const post = await getPost(slug);
return <article>{post.content}</article>;
}
import Link from "next/link";
import { useRouter } from "next/navigation";
function Navigation() {
const router = useRouter();
return (
<nav>
<Link href="/about">About</Link>
<Link href="/blog/[slug]" as="/blog/hello-world">
Blog Post
</Link>
<button onClick={() => router.push("/dashboard")}>Dashboard</button>
</nav>
);
}
Loading UI:
// app/dashboard/loading.tsx
export default function Loading() {
return <div>Loading dashboard...</div>;
}
Error Handling:
// app/dashboard/error.tsx
"use client";
export default function Error({
error,
reset,
}: {
error: Error;
reset: () => void;
}) {
return (
<div>
<h2>Something went wrong!</h2>
<button onClick={() => reset()}>Try again</button>
</div>
);
}
// app/actions.ts
"use server";
export async function createPost(formData: FormData) {
const title = formData.get("title") as string;
// Database operation
revalidatePath("/blog"); // Update cache
}
// Usage in component
export default function CreatePostForm() {
return (
<form action={createPost}>
<input name="title" />
<button type="submit">Create Post</button>
</form>
);
}
// app/products/[id]/page.tsx
import Image from "next/image";
import AddToCart from "./add-to-cart";
async function getProduct(id: string) {
const res = await fetch(`https://api.example.com/products/${id}`);
return res.json();
}
export default async function ProductPage({
params,
}: {
params: Promise<{ id: string }>;
}) {
const { id } = await params;
const product = await getProduct(id);
return (
<div>
<Image src={product.image} alt={product.name} width={300} height={300} />
<h1>{product.name}</h1>
<p>{product.description}</p>
<p>${product.price}</p>
<AddToCart productId={product.id} />
</div>
);
}
// app/blog/page.tsx
import BlogList from "./blog-list";
import SearchForm from "./search-form";
export default async function BlogPage({
searchParams,
}: {
searchParams: Promise<{ query?: string }>;
}) {
const { query } = await searchParams;
const posts = await getPosts(query);
return (
<div>
<SearchForm initialQuery={query} />
<BlogList posts={posts} />
</div>
);
}
// app/dashboard/page.tsx
import { Suspense } from "react";
import StatsCard from "./stats-card";
import RecentActivity from "./recent-activity";
export default function Dashboard() {
return (
<div>
<h1>Dashboard</h1>
<Suspense fallback={<div>Loading stats...</div>}>
<StatsCard />
</Suspense>
<Suspense fallback={<div>Loading activity...</div>}>
<RecentActivity />
</Suspense>
</div>
);
}