Setting up MongoDB

1: Create new cluster

Create a new project and a new cluster in MongoDB Atlas. I select Azure as my cloud provider and name my cluster v1. I select the M0 free tier - it caps at 512 MB but that's no big deal because the entirety of Postulate is 13MB (as of last week).

Then, click "connect," allow access from anywhere with the 0.0.0.0/0 IP address, and select "from driver." I get a string that starts with mongodb+srv:// , and I add it as an environment variable, stored in a .env file in the root directory of our project.

MongoDB tells you to replace myFirstDatabase in the URL with a database name, which confused me as no further explanation was provided and I was doing this for the first time. I'll spare you some head banging and here's the answer: basically, you can replace it with whatever you want your database to be named as. I name mine v1 .

2. Connect to the database from your project

Install mongoose in your Next.js project via npm i mongoose @types/mongoose .

Create utils/dbConnnect.ts - a utility function to reuse database connections. I got this code from the Postulate repository:

// from https://github.com/vercel/next.js/blob/canary/examples/with-mongodb-mongoose/utils/dbConnect.js



import mongoose from "mongoose";



const MONGODB_URL = process.env.MONGODB_URL // access environment variable



if (!MONGODB_URL) {

throw new Error(

'Please define the MONGODB_URL environment variable inside .env'

)

}



async function dbConnect() {

// check if we have a connection to the database or if it's currently

// connecting or disconnecting (readyState 1, 2 and 3)

if (mongoose.connection.readyState >= 1) {

return;

}



return mongoose.connect(MONGODB_URL, {

useNewUrlParser: true,

useUnifiedTopology: true,

useFindAndModify: false,

useCreateIndex: true,

maxIdleTimeMS: 10000,

socketTimeoutMS: 20000,

});

}



export default dbConnect;

Here's where the earlier environment variable comes in handy. We access it with process.env.MONGODB_URL .

3. Set up models

Following the tree that Samson laid out earlier in the PM spec, I create models. In models folder, create Typescript files, each exporting one model. For example, here is models/account.ts :

import mongoose, {Model, Document} from "mongoose";

import {AccountObj} from "../utils/types";



const AccountSchema = new mongoose.Schema({

email: {type: String, required: true},

name: {type: String, required: true},

image: {type: String, required: true},

trialExpDate: {type: String, required: true},

}, {

timestamps: true,

})



export const AccountModel: Model<Document<AccountObj>> = mongoose.models.account || mongoose.model("account", AccountSchema);

And here is the corresponding Typescript type in utils/types.ts:

export interface AccountObj {

email: string,

name: string,

image: string,

trialExpDate: string // date string

}

With that, we have successfully set up our database!

Bonus: To verify that the configuration is correct, I can create an account from my Next app and store it in MongoDB after setting up NextAuth. To see our data, go to Clusters > v1 > Collections, and everything looks awesome 😁