expressjs_com/
Express JS
Fast, unopinionated, minimalist web framework for Node.js
$ npm install express --savev PS C:\nodeproject> npm install express --save
expressjs_com/en/starter/hello-world.html
mongoose
mongoosejs/docs/
npm install mongoose --save
cors
CORS is a node.js package for providing a Connect/Express middleware that can be used to enable CORS with various options.
npmjs-com/package/cors
PS C:\nodeproject>npm i cors
run PS C:\nodeproject> node index.js
index.js
//index.js
const express = require('express')
const mongoose = require('mongoose')
const cors = require('cors')
const UserModel = require('./User')
const app = express()
const port = 3001
app.use(cors())
app.use(express.json())
main().catch(err => console.log(err));
async function main() {
try { //"mongodb+srv://"username":"password"@cluster0.x45tgvn.mongodb.net/"databasename"?retryWrites=true&w=majority&appName=Cluster0"
await mongoose.connect('mongodb+srv://cairocoders:123456@cluster0.x45tgvn.mongodb.net/expressdb?retryWrites=true&w=majority&appName=Cluster0', {});
console.log("CONNECTED TO DATABASE SUCCESSFULLY");
} catch (error) {
console.error('COULD NOT CONNECT TO DATABASE:', error.message);
}
}
app.get('/', (req, res) => {
res.send('Hello World!')
})
//Pagination
app.get("/pagination", async (req, res) => {
let { page, limit } = req.query;
if (!page) page = 1;
if (!limit) limit = 2;
const skip = (page - 1) * 2;
const users = await UserModel.find().sort({ "_id":-1})
.skip(skip)
.limit(limit);
const total = await UserModel.find().countDocuments()
res.header('Access-Control-Expose-Headers', 'X-Total-Count')
res.header('X-Total-Count', total)
res.send({ page: page, limit: limit, users: users });
});
app.get('/users', (req, res) => {
UserModel.find()
.then(users => res.json(users))
.catch(err => res.json(err))
})
app.post('/users/create', (req, res) => {
UserModel.create(req.body)
.then(user => res.json(user))
.catch(err => res.json(err))
})
app.get('/users/get/:id', (req, res) => {
const id = req.params.id
UserModel.findById({_id: id})
.then(post => res.json(post))
.catch(err => console.log(err))
})
app.put('/users/update/:id', (req, res) => {
const id = req.params.id;
UserModel.findByIdAndUpdate({_id: id}, {
name: req.body.name,
email: req.body.email,
age: req.body.age
}).then(user => res.json(user))
.catch(err => res.json(err))
})
app.delete('/users/delete/:id', (req, res) => {
const id = req.params.id;
UserModel.findByIdAndDelete({_id: id})
.then(response => res.json(response))
.catch(err => res.json(err))
})
app.listen(port, () => {
console.log(`Example app listening on port ${port}`)
})
User.js
//User.js
const mongoose = require('mongoose')
const UserSchema = new mongoose.Schema({
name: String,
email: String,
age: Number
})
const UserModel = mongoose.model("users", UserSchema)
module.exports = UserModel;
Install nextjs npx create-next-app@latest nextjs_org/docs/getting-started/installation Install react-query
npm i @tanstack/react-query
tanstack_com/query/latest/docs/framework/react/installation
app\page.tsx
//app\page.tsx
"use client";
import { useQuery } from "@tanstack/react-query"; //npm i @tanstack/react-query tanstack_com/query/latest/docs/framework/react/installation
import UserList from "./components/UserList";
import { getUserList } from "./api/users";
import AddUser from './components/AddUser'
import LoadingSpinner from "./components/LoadingSpinner";
import Paginationnumber from "./components/Paginationnumber";
import { useSearchParams } from 'next/navigation'
export default function Home() {
const searchParams = useSearchParams()
const page = searchParams.get('page')
//console.log(page);
//const page = 1
const currentPage = Number(page) || 1;
const { isLoading, data, isError, isFetching, error } = useQuery({
queryKey: ["users", currentPage],
queryFn: () => getUserList(currentPage)
});
//console.log(data);
if (isLoading) return "Loading...";
if (isError) return `Error: ${error.message}`;
const ITEMS_PER_PAGE = 3;
const totalPages = Math.ceil(Number(data.totalData) / ITEMS_PER_PAGE);
return (
<div className="w-screen py-20 flex justify-center flex-col items-center">
<div className="flex items-center justify-between gap-1 mb-5 pl-10 pr-5">
<h1 className="text-4xl font-bold">Nextjs 15 CRUD (Create, Read, Update and Delete) with Pagination Tanstack Query | Node Express MongoDB Atlas</h1>
</div>
<div className="overflow-x-auto py-10">
<AddUser/>
<UserList userlist={data.userlist} />
<div className="flex items-center justify-between my-5">
<Paginationnumber totalPages={totalPages} />
{isFetching ? <LoadingSpinner /> : null}
</div>
</div>
</div>
);
}
app\layout.tsx
//app\layout.tsx
import type { Metadata } from "next";
import { Geist, Geist_Mono } from "next/font/google";
import "./globals.css";
import QueryProvider from "./components/QueryProvider";
const geistSans = Geist({
variable: "--font-geist-sans",
subsets: ["latin"],
});
const geistMono = Geist_Mono({
variable: "--font-geist-mono",
subsets: ["latin"],
});
export const metadata: Metadata = {
title: "Create Next App",
description: "Generated by create next app",
};
export default function RootLayout({
children,
}: Readonly<{
children: React.ReactNode;
}>) {
return (
<html lang="en">
<body
className={`${geistSans.variable} ${geistMono.variable} antialiased`}
>
<QueryProvider>{children}</QueryProvider>
</body>
</html>
);
}
app\components\QueryProvider.tsx
//app\components\QueryProvider.tsx
"use client";
import { QueryClientProvider, QueryClient } from "@tanstack/react-query";
import { useState } from "react";
interface Props {
children: React.ReactNode;
}
export default function QueryProvider({ children }: Props) {
const [queryClient] = useState(() => new QueryClient());
return (
<QueryClientProvider client={queryClient}> {children} </QueryClientProvider>
);
}
app\components\AddUser.tsx
//app\components\AddUser.tsx
import { useMutation, useQueryClient } from "@tanstack/react-query"
import UserForm from "./UserForm"
import { v4 as uuidv4 } from 'uuid'; //npm i uuid
import { createUser } from "../api/users"
const AddUser = () => {
const queryClient = useQueryClient();
const createUserMutation = useMutation({
mutationFn: createUser,
onSuccess: () => {
queryClient.invalidateQueries({ queryKey: ['users']});
console.log("success!")
}
});
const handleAddPost = (user) => {
createUserMutation.mutate({
id: uuidv4(),
...user
})
}
return (
<div className="max-w-md mx-auto mt-5 mb-5">
<h1 className="text-2xl text-center mb-2">Add New User</h1>
<UserForm onSubmit={handleAddPost} initialValue={{}} />
</div>
)
}
export default AddUser
app\components\UserForm.tsx
//app\components\UserForm.tsx
import { useState } from "react"
const UserForm = ({ onSubmit, initialValue }) => {
const [user, setUser] = useState({
name: initialValue.name || "",
email: initialValue.email || "",
age: initialValue.age || ""
});
const handleChangeInput = (e) => {
setUser({
...user,
[e.target.name]: e.target.value
})
}
const renderField = (label) => (
<div>
<label className="block text-sm font-medium text-gray-900">{label}</label>
<input onChange={handleChangeInput} type="text" name={label.toLowerCase()} value={user[label.toLowerCase()]}
className="bg-gray-50 border border-gray-300 text-gray-900 text-sm rounded-lg focus:ring-blue-500 focus:border-blue-500 block w-full p-2.5 dark:bg-gray-700 dark:border-gray-600 dark:placeholder-gray-400 dark:text-white dark:focus:ring-blue-500 dark:focus:border-bg-gray-50 border border-gray-300 text-gray-900 text-sm rounded-lg focus:ring-blue-500 focus:border-blue-500 block w-full p-2.5 dark:bg-gray-700 dark:border-gray-600 dark:placeholder-gray-400 dark:text-white dark:focus:ring-blue-500 dark:focus:border-blue-500blue-500"
/>
</div>
);
const handleSubmit = (e) => {
e.preventDefault();
onSubmit(user);
setUser({
name: "",
email: "",
age: ""
})
}
return (
<form onSubmit={handleSubmit}>
<div className="mb-5">{renderField('Name')}</div>
<div className="mb-5">{renderField('Email')}</div>
<div className="mb-5">{renderField('Age')}</div>
<button type="submit"
className="text-white bg-blue-700 hover:bg-blue-800 focus:ring-4 focus:outline-none focus:ring-blue-300 font-medium rounded-lg text-sm w-full sm:w-auto px-5 py-2.5 text-center dark:bg-blue-600 dark:hover:bg-blue-700 dark:focus:ring-blue-800"
>
Submit</button>
</form>
)
}
export default UserForm
app\components\UserList.tsx
//app\components\UserList.tsx
import Link from "next/link";
import { useMutation, useQueryClient } from "@tanstack/react-query"; //npm i @tanstack/react-query
import { deleteUser } from "../api/users";
const UserList = ({ userlist }) => {
const queryClient = useQueryClient();
const deleteUserMutation = useMutation({
mutationFn: deleteUser,
onSuccess: () => {
queryClient.invalidateQueries({ queryKey: ['users']});
}
});
const handleDelete = (id) => {
deleteUserMutation.mutate(id)
}
return (
<table className="table table-zebra">
<thead className="text-sm text-gray-700 uppercase bg-gray-50">
<tr>
<th className="py-3 px-6">#</th>
<th className="py-3 px-6">Name</th>
<th className="py-3 px-6">Email</th>
<th className="py-3 px-6">Age</th>
<th className="py-3 px-6 text-center">Actions</th>
</tr>
</thead>
<tbody>
{userlist.map((user) => (
<tr key={user._id} className="bg-white border-b text-black">
<td className="py-3 px-6">{user._id}</td>
<td className="py-3 px-6">{user.name}</td>
<td className="py-3 px-6">{user.email}</td>
<td className="py-3 px-6">{user.age}</td>
<td className="flex justify-center gap-1 py-3">
<Link className="text-white bg-blue-700 hover:bg-blue-800 focus:ring-4 focus:ring-blue-300 font-medium rounded-lg text-sm px-5 py-2.5 me-2 mb-2 dark:bg-blue-600 dark:hover:bg-blue-700 focus:outline-none dark:focus:ring-blue-800"
href={`/user/${user._id}`}>Read</Link>
<Link className="focus:outline-none text-white bg-yellow-400 hover:bg-yellow-500 focus:ring-4 focus:ring-yellow-300 font-medium rounded-lg text-sm px-5 py-2.5 me-2 mb-2 dark:focus:ring-yellow-900"
href={`/user/edit/${user._id}/`}>
Edit
</Link>
<button onClick={() => handleDelete(user._id)} className="focus:outline-none text-white bg-red-700 hover:bg-red-800 focus:ring-4 focus:ring-red-300 font-medium rounded-lg text-sm px-5 py-2.5 me-2 mb-2 dark:bg-red-600 dark:hover:bg-red-700 dark:focus:ring-red-900">
Delete</button>
</td>
</tr>
))}
</tbody>
</table>
)
}
export default UserList
app\components\LoadingSpinner.tsx
//app\components\LoadingSpinner.tsx
export default function LoadingSpinner() {
return (
<h1>Loading...</h1>
)
}
app\components\Paginationnumber.tsx
//app\components\Paginationnumber.tsx
"use client";
import Link from "next/link";
import { HiChevronLeft, HiChevronRight } from "react-icons/hi"; //npm install react-icons --save npmjs_com/package/react-icons
import { usePathname, useSearchParams } from "next/navigation";
import clsx from "clsx"; //npm i clsx npmjs_com/package/clsx
export const generatePagination = (currentPage: number, totalPages: number) => {
if (totalPages <= 7) {
return Array.from({ length: totalPages }, (_, i) => i + 1);
}
if (currentPage <= 3) {
return [1, 2, 3, "...", totalPages - 1, totalPages];
}
if (currentPage >= totalPages - 2) {
return [1, 2, 3, "...", totalPages - 2, totalPages - 1, totalPages];
}
return [
1,
"...",
currentPage - 1,
currentPage,
currentPage + 1,
"...",
totalPages,
];
};
const Paginationnumber = ({ totalPages }: { totalPages: number }) => {
const pathname = usePathname();
const searchParams = useSearchParams();
const currentPage = Number(searchParams.get("page")) || 1;
const createPageURL = (pageNumber: string | number) => {
const params = new URLSearchParams(searchParams);
params.set("page", pageNumber.toString());
return `${pathname}?${params.toString()}`;
};
const allPages = generatePagination(currentPage, totalPages);
const PaginationNumber = ({
page,
href,
position,
isActive,
}: {
page: number | string;
href: string;
position?: "first" | "last" | "middle" | "single";
isActive: boolean;
}) => {
const className = clsx(
"flex h-10 w-10 items-center justify-center text-sm border",
{
"rounded-l-sm": position === "first" || position === "single",
"rounded-r-sm": position === "last" || position === "single",
"z-10 bg-blue-100 border-blue-500 text-white bg-blue-700": isActive,
"hover:bg-blue-700": !isActive && position !== "middle",
"text-gray-300 pointer-events-none": position === "middle",
}
);
return isActive && position === "middle" ? (
<div className={className}>{page}</div>
) : (
<Link href={href} className={className}>
{page}
</Link>
);
};
const PaginationArrow = ({
href,
direction,
isDisabled,
}: {
href: string;
direction: "left" | "right";
isDisabled?: boolean;
}) => {
const className = clsx(
"flex h-10 w-10 items-center justify-center text-sm border",
{
"pointer-events-none text-gray-300": isDisabled,
"hover:bg-gray-100": !isDisabled,
"mr-2": direction === "left",
"ml-2": direction === "right",
}
);
const icon =
direction === "left" ? (
<HiChevronLeft size={20} />
) : (
<HiChevronRight size={20} />
);
return isDisabled ? (
<div className={className}>{icon}</div>
) : (
<Link href={href} className={className}>
{icon}
</Link>
);
};
return (
<div className="inline-flex">
<PaginationArrow
direction="left"
href={createPageURL(currentPage - 1)}
isDisabled={currentPage <= 1}
/>
<div className="flex -space-x-px">
{allPages.map((page, index) => {
let position: "first" | "last" | "single" | "middle" | undefined;
if (index === 0) position = "first";
if (index === allPages.length - 1) position = "last";
if (allPages.length === 1) position = "single";
if (page === "...") position = "middle";
return (
<PaginationNumber
key={index}
href={createPageURL(page)}
page={page}
position={position}
isActive={currentPage === page}
/>
);
})}
</div>
<PaginationArrow
direction="right"
href={createPageURL(currentPage + 1)}
isDisabled={currentPage >= totalPages}
/>
</div>
);
};
export default Paginationnumber;
app\user\[id]\page.tsx
//app\user\[id]\page.tsx
"use client";
import { useQuery } from "@tanstack/react-query"; //npm i @tanstack/react-query
import { useParams } from 'next/navigation'
import { fetchUser } from "../../api/users";
const User = () => {
const {id}=useParams();
const {
isLoading,
isError,
data: user,
error,
} = useQuery({
queryKey: ["users", id],
queryFn: () => fetchUser(id),
});
if (isLoading) return "loading...";
if (isError) return `Error: ${error.message}`;
return (
<div className="w-screen py-20 flex justify-center flex-col items-center">
<div className="flex items-center justify-between gap-1 mb-5">
<h1 className="text-4xl font-bold">{user.name}</h1>
</div>
<div className="overflow-x-auto py-10">
<h2>{user.email}</h2>
<h3>{user.age}</h3>
</div>
</div>
)
}
export default User
app\user\edit\[id]\page.tsx
//app\user\edit\[id]\page.tsx
"use client";
import { useMutation, useQuery, useQueryClient } from "@tanstack/react-query";
import { useParams, useRouter } from 'next/navigation'
import { fetchUser, updateUser } from "../../../api/users";
import UserForm from "../../../components/UserForm"
const EditUser = () => {
const {id}=useParams();
//console.log(id);
const queryClient = useQueryClient();
const router = useRouter();
const {
isLoading,
isError,
data: user,
error,
} = useQuery({
queryKey: ["users", id],
queryFn: () => fetchUser(id),
});
const updateUserMutation = useMutation({
mutationFn: updateUser,
onSuccess: () => {
queryClient.invalidateQueries({ queryKey: ['users']});
router.push('/')
}
})
if (isLoading) return "loading...";
if (isError) return `Error: ${error.message}`;
const handleSubmit = (updatedUser) => {
updateUserMutation.mutate({id, ...updatedUser})
}
return (
<div className="max-w-md mx-auto mt-5">
<div className="flex items-center justify-between gap-1 mb-5">
<h1 className="text-4xl font-bold">{user.name}</h1>
</div>
<UserForm onSubmit={handleSubmit} initialValue={user} />
</div>
)
}
export default EditUser
app\api\page.tsx
//app\api\page.tsx
const ITEM_PER_PAGE = 3;
export async function getUserList(page) {
const response = await fetch(`http://localhost:3001/pagination?page=${page}&limit=${ITEM_PER_PAGE}`);
const totalData = response.headers.get('X-Total-Count');
const data = await response.json();
//console.log(totalData);
return {
userlist: data.users,
totalData
}
}
export async function fetchUsers() {
const response = await fetch('http://localhost:3001/users');
return response.json()
}
export async function createUser(newUser) {
const response = await fetch(`http://localhost:3001/users/create`, {
method: "POST",
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify(newUser)
});
return response.json()
}
export async function fetchUser(id) {
const response = await fetch(`http://localhost:3001/users/get/${id}`);
return response.json()
}
export async function updateUser(updatedUser) {
const response = await fetch(`http://localhost:3001/users/update/${updatedUser.id}`, {
method: "PUT",
headers: {
"Content-Type": "application/json"
},
body: JSON.stringify(updatedUser)
});
return response.json()
}
export async function deleteUser(id) {
const response = await fetch(`http://localhost:3001/users/delete/${id}`, {
method: "DELETE",
});
return response.json()
}
run C:\nextjs>npm run dev 
