Node.js: مشروع RESTful API

book-api/
├── app.js
├── routes/
│   └── books.js
├── controllers/
│   └── bookController.js
├── middleware/
│   ├── validate.js
│   └── errorHandler.js
└── models/
    └── bookModel.js

{
  "success": true,
  "data": { "id": 1, "title": "Node.js Guide", "author": "Alice" }
}

{
  "success": false,
  "error": { "code": 404, "message": "Book not found" }
}

const books = [
  { id: 1, title: "Node.js Guide", author: "Alice", year: 2024 }
];

let nextId = 2;

function findAll() {
  return books;
}

function findById(id) {
  return books.find(b => b.id === id);
}

function create(data) {
  const book = { id: nextId++, ...data };
  books.push(book);
  return book;
}

function update(id, data) {
  const index = books.findIndex(b => b.id === id);
  if (index === -1) return null;
  books[index] = { ...books[index], ...data };
  return books[index];
}

function remove(id) {
  const index = books.findIndex(b => b.id === id);
  if (index === -1) return false;
  books.splice(index, 1);
  return true;
}

module.exports = { findAll, findById, create, update, remove };

function validateBook(req, res, next) {
  const { title, author, year } = req.body;
  const errors = [];
  if (!title || typeof title !== "string") {
    errors.push("title is required and must be a string");
  }
  if (!author || typeof author !== "string") {
    errors.push("author is required and must be a string");
  }
  if (year !== undefined && (typeof year !== "number" || year < 0)) {
    errors.push("year must be a non-negative number");
  }
  if (errors.length > 0) {
    return res.status(400).json({
      success: false,
      error: { code: 400, message: errors.join("; ") }
    });
  }
  next();
}

module.exports = { validateBook };

function errorHandler(err, req, res, next) {
  console.error(err.stack);
  const status = err.status || 500;
  res.status(status).json({
    success: false,
    error: { code: status, message: err.message || "Internal Server Error" }
  });
}

function createError(status, message) {
  const err = new Error(message);
  err.status = status;
  return err;
}

module.exports = { errorHandler, createError };

const Book = require("../models/bookModel");
const { createError } = require("../middleware/errorHandler");

function getAllBooks(req, res) {
  res.json({ success: true, data: Book.findAll() });
}

function getBookById(req, res, next) {
  const book = Book.findById(Number(req.params.id));
  if (!book) return next(createError(404, "Book not found"));
  res.json({ success: true, data: book });
}

function createBook(req, res) {
  const book = Book.create(req.body);
  res.status(201).json({ success: true, data: book });
}

function updateBook(req, res, next) {
  const book = Book.update(Number(req.params.id), req.body);
  if (!book) return next(createError(404, "Book not found"));
  res.json({ success: true, data: book });
}

function deleteBook(req, res, next) {
  const removed = Book.remove(Number(req.params.id));
  if (!removed) return next(createError(404, "Book not found"));
  res.json({ success: true, data: { message: "Book deleted" } });
}

module.exports = { getAllBooks, getBookById, createBook, updateBook, deleteBook };

const express = require("express");
const router = express.Router();
const controller = require("../controllers/bookController");
const { validateBook } = require("../middleware/validate");

router.get("/", controller.getAllBooks);
router.get("/:id", controller.getBookById);
router.post("/", validateBook, controller.createBook);
router.put("/:id", validateBook, controller.updateBook);
router.delete("/:id", controller.deleteBook);

module.exports = router;

const express = require("express");
const booksRoute = require("./routes/books");
const { errorHandler } = require("./middleware/errorHandler");

const app = express();
app.use(express.json());

app.use("/api/books", booksRoute);
app.use(errorHandler);

const PORT = 3000;
app.listen(PORT, () => console.log(`Server running on port ${PORT}`));

# Add a book
curl -X POST -H "Content-Type: application/json" \
  -d '{"title":"Express in Action","author":"Evan","year":2024}' \
  localhost:3000/api/books

{"success":true,"data":{"id":2,"タイトル":"Express in Action","author":"Evan","year":2024}}

# Search All Books
curl localhost:3000/api/books

{"success":true,"data":[{"id":1,"title":"Node.js Guide","author":"Alice","year":2024},{"id":2,"title":"Express in Action","author":"Evan","year":2024}]}

// models/bookModel.js
const books = [{ id: 1, title: "Node.js Guide", author: "Alice", year: 2024 }];
let nextId = 2;
function findAll() { return books; }
function findById(id) { return books.find(b => b.id === id); }
function create(data) {
  const book = { id: nextId++, ...data };
  books.push(book);
  return book;
}
function update(id, data) {
  const index = books.findIndex(b => b.id === id);
  if (index === -1) return null;
  books[index] = { ...books[index], ...data };
  return books[index];
}
function remove(id) {
  const index = books.findIndex(b => b.id === id);
  if (index === -1) return false;
  books.splice(index, 1);
  return true;
}
module.exports = { findAll, findById, create, update, remove };

// middleware/validate.js
function validateBook(req, res, next) {
  const { title, author } = req.body;
  const errors = [];
  if (!title || typeof title !== "string") errors.push("title is required");
  if (!author || typeof author !== "string") errors.push("author is required");
  if (errors.length > 0) {
    return res.status(400).json({
      success: false,
      error: { code: 400, message: errors.join("; ") }
    });
  }
  next();
}
module.exports = { validateBook };

// middleware/errorHandler.js
function errorHandler(err, req, res, next) {
  const status = err.status || 500;
  res.status(status).json({
    success: false,
    error: { code: status, message: err.message || "Internal Server Error" }
  });
}
function createError(status, message) {
  const err = new Error(message);
  err.status = status;
  return err;
}
module.exports = { errorHandler, createError };

// controllers/bookController.js
const Book = require("../models/bookModel");
const { createError } = require("../middleware/errorHandler");
function getAllBooks(req, res) {
  res.json({ success: true, data: Book.findAll() });
}
function getBookById(req, res, next) {
  const book = Book.findById(Number(req.params.id));
  if (!book) return next(createError(404, "Book not found"));
  res.json({ success: true, data: book });
}
function createBook(req, res) {
  const book = Book.create(req.body);
  res.status(201).json({ success: true, data: book });
}
function updateBook(req, res, next) {
  const book = Book.update(Number(req.params.id), req.body);
  if (!book) return next(createError(404, "Book not found"));
  res.json({ success: true, data: book });
}
function deleteBook(req, res, next) {
  const removed = Book.remove(Number(req.params.id));
  if (!removed) return next(createError(404, "Book not found"));
  res.json({ success: true, data: { message: "Book deleted" } });
}
module.exports = { getAllBooks, getBookById, createBook, updateBook, deleteBook };

// routes/books.js
const express = require("express");
const router = express.Router();
const ctrl = require("../controllers/bookController");
const { validateBook } = require("../middleware/validate");
router.get("/", ctrl.getAllBooks);
router.get("/:id", ctrl.getBookById);
router.post("/", validateBook, ctrl.createBook);
router.put("/:id", validateBook, ctrl.updateBook);
router.delete("/:id", ctrl.deleteBook);
module.exports = router;

// app.js
const express = require("express");
const booksRoute = require("./routes/books");
const { errorHandler } = require("./middleware/errorHandler");
const app = express();
app.use(express.json());
app.use("/api/books", booksRoute);
app.use(errorHandler);
app.listen(3000, () => console.log("Server running on port 3000"));

# Start and Test
node app.js
curl -X POST -H "Content-Type: application/json" \
  -d '{"title":"Clean Code","author":"Robert","year":2008}' \
  localhost:3000/api/books
curl localhost:3000/api/books/1
curl -X DELETE localhost:3000/api/books/1