Introduction

In modern web development, integrating a backend with a scalable database is essential for building dynamic applications. In this blog, we will explore how to create a RESTful API using Node.js, Express.js, and Supabase (a powerful open-source alternative to Firebase). This API will handle basic CRUD (Create, Read, Update, Delete) operations for user management.

Why Supabase?

Supabase is an open-source backend-as-a-service (BaaS) that provides features like:

  • PostgreSQL database with real-time capabilities
  • Authentication and authorization
  • Storage for managing files
  • Auto-generated APIs for database interactions

With Supabase, you get a fully managed PostgreSQL database with an easy-to-use JavaScript SDK.

Tech Stack

  • Node.js: Server-side JavaScript runtime
  • Express.js: Minimalist web framework for Node.js
  • Supabase: PostgreSQL-based backend
  • dotenv: For managing environment variables
  • Swagger: API documentation tool
  • CORS: Enables cross-origin resource sharing

Project Setup

1. Clone the Repository 

git clone https://github.com/manthanank/nodejs-supabase.git
cd nodejs-supabase

2. Install Dependencies 

npm install

3. Configure Environment Variables

Create a .env file and add your Supabase credentials:

SUPABASE_URL=https://your-project-url.supabase.co
SUPABASE_KEY=your-anon-or-service-role-key
PORT=5000

4. Run the Application

Start the development server:

npm run dev

For production:

npm start

Your API will now be running at http://localhost:5000.

Project Structure 

nodejs-supabase
├── .env                   # Environment variables
├── index.js               # Main application entry point
├── package.json           # Project dependencies and scripts
├── README.md              # Project documentation
├── config/
│   ├── supabaseClient.js  # Supabase client configuration
│   └── swagger.js         # Swagger configuration
├── controllers/
│   └── userController.js  # User controller functions
├── routes/
│   └── userRoutes.js      # API route definitions with Swagger docs
└── services/
    └── userService.js     # Business logic for user operations

API Endpoints

Users CRUD Operations

Method Endpoint Description
POST /api/users Create a new user
GET /api/users Get all users
GET /api/users/search?query=name Search users by name
GET /api/users/:id Get user by ID
GET /api/users/email/:email Get user by email
PUT /api/users/:id Update user by ID
DELETE /api/users/:id Delete user by ID

Key Implementations

Supabase Client Setup

Create config/supabaseClient.js:

import { createClient } from "@supabase/supabase-js";
import dotenv from "dotenv";

dotenv.config();

const supabase = createClient(
  process.env.SUPABASE_URL,
  process.env.SUPABASE_KEY
);

export default supabase;

CRUD Operations in userService.js

Create User 

export const createUser = async (userData) => {
  const { data, error } = await supabase
    .from("users")
    .insert([userData])
    .select();

  if (error) throw new Error(error.message);
  return data;
};

Fetch Users 

export const getUsers = async () => {
  const { data, error } = await supabase.from("users").select("*");

  if (error) throw new Error(error.message);
  return data;
};

Update User 

export const updateUser = async (id, updates) => {
  const { data, error } = await supabase
    .from("users")
    .update(updates)
    .eq("id", id)
    .select();

  if (error) throw new Error(error.message);
  return data;
};

Delete User 

export const deleteUser = async (id) => {
  const { error } = await supabase
    .from("users")
    .delete()
    .eq("id", id);

  if (error) throw new Error(error.message);
  return { success: true, message: "User deleted successfully" };
};

API Routes in userRoutes.js 

import express from "express";
import { addUser, fetchUsers, fetchUserById, fetchUserByEmail, modifyUser, removeUser } from "../controllers/userController.js";

const router = express.Router();

router.post("/users", addUser);
router.get("/users", fetchUsers);
router.get("/users/:id", fetchUserById);
router.get("/users/email/:email", fetchUserByEmail);
router.put("/users/:id", modifyUser);
router.delete("/users/:id", removeUser);

export default router;

Testing the API

Create a User 

curl -X POST http://localhost:5000/api/users \
  -H "Content-Type: application/json" \
  -d '{"name": "John Doe", "email": "[email protected]", "age": 30}'

Search Users 

curl -X GET http://localhost:5000/api/users/search?query=John

Swagger API Documentation

To enable API documentation, navigate to:

http://localhost:5000/api-docs

This provides an interactive UI for testing endpoints.

Conclusion

In this blog, we covered how to build a CRUD API using Node.js, Express.js, and Supabase. Supabase simplifies database management while offering powerful features like authentication and real-time updates. By integrating Swagger, we also ensured that our API is well-documented and easy to use.

This API can be extended with additional functionalities like authentication, role-based access control, and real-time updates.

Happy coding! 🚀

Exploring the Code

Visit the GitHub repository to explore the code in detail.