This gist was created by using a reference article by Roopali Singh in Medium.com.
npm install mongoose
Create userModel.js with userSchema for database structure
// userModel.js
import mongoose from "mongoose";
const userSchema = new mongoose.Schema(
{
// It atomatically assigns a unique _id, so we don't need to define another id for it.
firstName: { type: String, required: true },
lastName: { type: String, required: false },
email: { type: String, required: true, unique: true },
pin: { type: Number, required: true },
},
{
timestamps: true,
// Timestamp of creating a record and last update of record.
}
);Create mongoose model to call on userSchema:
const User = mongoose.model("User", userSchema);
export default User;Create userRouter.js file to set API routes for CRUD operations
import express from "express";
import User from "./userModel.js ";
// express.Router() => a function to make code Modular, instead of
// creating all routes in server.js we can define multiple files
// to have our routers...
const userRouter = express.Router();
// nature of mongoose operation is async
// so we will define the async functions here.
export default userRouter;Connect mongoose to database with server.js file
// server.js file will connect userRouter.js to database
import express from "express";
import mongoose from "mongoose";
mongoose.connect(process.env.MONGODB_URL ||
"mongodb://localhost/your_app_name", {
useNewUrlParser: true,
useUnifiedTopology: true,
useCreateIndex: true,
});Import userRouter into server.js to connect server.js to userRouter.js
import userRouter from "./userRouter.js";
app.use("/api/users", userRouter);Now, server.js looks like this:
import express from "express";
import dotenv from "dotenv"; // npm install dotenv
import mongoose from "mongoose";
import userRouter from "./router/userRouter.js";
dotenv.config(); // to use .env file content
const app = express();
app.use(express.json());
app.use(express.urlencoded({ extended: true }));
// To connect mongoose to mongoDB database
mongoose.connect(process.env.MONGODB_URL ||
"mongodb://localhost/your_app_name", {
useNewUrlParser: true,
useUnifiedTopology: true,
useCreateIndex: true,
});
// To connect server.js to userRouter.js
app.use("/api/users", userRouter);
// listen command
const port = process.env.PORT || 5000;
app.listen(port, () => {
console.log(`Serve at http://localhost:${port}`);
});Return to userRouter.js file to create routes for CRUD operations:
// userRouter.js
import express from "express";
import User from "./userModel.js ";
const userRouter = express.Router();
// 1) to read/fetch all users:
userRouter.get(
"/seed",async (request, response) => {
// there is no condition defined in find, so it will
// fetch all users.
const allUsers = await User.find({});
response.send({ allUsers });
};
);
// 2) to create new user:
userRouter.post(
"/register",async (request, response) => {
// A request body is data sent by the client to your API.
const newUser = new User({
firstName: request.body.firstName,
lastName: request.body.lastName,
email: request.body.email,
pin: request.body.pin,
});
const createdUser = await newUser.save();
response.send({ createdUser });
};
);
// 3) to update existing user:
// first we need to find that user and then update its info.
userRouter.post(
"/update",async (request, response) => {
const editUser = await User.find({ email: request.body.email });
// When there are no matches find() returns [].
// So we could not use the condition: if(!editUser){...}
if (!editUser.length) {
response.status(400).send({ message: "No User Found" });
} else {
editUser.firstName: request.body.firstName,
editUser.lastName: request.body.lastName,
editUser.pin: request.body.pin,
const updatedUser = await editUser.save();
response.status(201).send({ updatedUser });
}
};
);
// 4) to delete a user:
// first we need to find that user and then delete it.
userRouter.delete(
"/delete",async (request, response) => {
const deleteUser = await User.find({ email: request.body.email });
if (!deleteUser.length) {
response.status(400).send({ message: "No User Found" });
} else {
const userDeleted = await deleteUser.deleteOne();
response.status(201).send({ message: "User removed" });
}
};
);
export default userRouter;Now it's possible to make request to server for desired data, such as:
GET request to fetch all users: /api/users/seed
Thank you to the author of this article posted in Medium.com, for helping me understand how to structure web app integration with MongoDB using Mongoose!
I am a new web developer learning MERN stack applications