Node, Express and MongoDB

Overview

This is an easy, basic and raw example of HOW to implement an API with Node, Express and MongoDB/Atlas (with Mongoose ODM).

Requirements

• Node 12+
• NPM
• MongoDB
• Mongoose ODM
• Optional: MongoDB account

Install dependencies

npm install

Environment variables

Create your env file from the sample. The app loads src/config/<ENVIRONMENT>.env, so create dev.env for npm run dev and prod.env for npm start:

cp src/config/.env.example src/config/dev.env

Fill in your MongoDB Atlas connection (DB_USER, DB_PASSWORD, DB_HOST, DB_NAME).

Installs use legacy-peer-deps (set in .npmrc) because the pinned 2021 dev tooling predates npm 7's stricter peer-dependency resolution.

Running the server

Development

npm run dev

Production

npm run build

npm start

API endpoints

GET /api/users

• Returns an object with the key data containing an array of objects with 40 records.
• Supports query string:
  • ?limit=integer
  • ?offset=integer

Request:

curl http://127.0.0.1:3333/api/users

Sample response:

{
  "data": [
    {
      "_id": "60da6b74fc13ae7069000d4b",
      "firstname": "Dedra",
      "lastname": "Demangel",
      "age": 96,
      "gender": "Agender",
      "username": "ddemangel3",
      "company": "Skidoo",
      "email": "ddemangel3@networkadvertising.org",
      "phone": "759-142-2883",
      "address": "4 Fisk Drive"
    },
    {
      "_id": "60da6b74fc13ae7069000d48",
      "firstname": "Martynne",
      "lastname": "Pimmocke",
      "age": 79,
      "gender": "Female",
      "username": "mpimmocke0",
      "company": "Edgeify",
      "email": "mpimmocke0@amazonaws.com",
      "phone": "354-508-5487",
      "address": "20633 Stone Corner Trail"
    }
  ]
}

Query string

GET /api/users?limit=1

• Returns n record(s) where n is the value (type: Number) of the limit key.

Request:

curl http://127.0.0.1:3333/api/users?limit=1

Response:

{
  "data": [
    {
      "_id": "60da6b74fc13ae7069000d4b",
      "firstname": "Dedra",
      "lastname": "Demangel",
      "age": 96,
      "gender": "Agender",
      "username": "ddemangel3",
      "company": "Skidoo",
      "email": "ddemangel3@networkadvertising.org",
      "phone": "759-142-2883",
      "address": "4 Fisk Drive"
    }
  ]
}

A non-numeric value falls back to the default (limit 40, offset 0). Example: users?limit=%27Hello%27 returns the first 40 users.

GET /api/users?offset=10

• Returns from n (PRIMARY KEY) where n is the value (type: Number) of the offset key.

Request:

curl http://127.0.0.1:3333/api/users?offset=10

Response:

{
  "data": [
    {
      "_id": "60da6b74fc13ae7069000d55",
      "firstname": "Cindi",
      "lastname": "Harnell",
      "age": 57,
      "gender": "Bigender",
      "username": "charnelld",
      "company": "Skyble",
      "email": "charnelld@networkadvertising.org",
      "phone": "176-961-8815",
      "address": "09953 Susan Alley"
    },
    {
      "_id": "60da6b74fc13ae7069000d57",
      "firstname": "Olva",
      "lastname": "Hoodless",
      "age": 61,
      "gender": "Female",
      "username": "ohoodlessf",
      "company": "Jaloo",
      "email": "ohoodlessf@illinois.edu",
      "phone": "886-598-0586",
      "address": "8 Chinook Pass"
    }
  ]
}

GET /latency

• Returns an object with a delay of 1 second (default)
• Supports query string:
  • ?delay=integer (milliseconds, min 1000, max 4000)

Request:

curl http://127.0.0.1:3333/latency

Response:

{
  "data": "Thanks for waiting 1 second"
}

Query string

GET /latency?delay=2000

• Increases latency (delay) to n milliseconds where, min:1000 and max:4000. Default value: 1000ms.

Wrong type for n value will produce a default delay of 1000ms.

Request:

curl http://127.0.0.1:3333/latency?delay=2000

Response:

{
  "data": "Thanks for waiting 2 seconds"
}

GET everything else

• Any other endpoint will retrieve an object

Request:

curl http://127.0.0.1:3333/

Response:

{
  "message": "Node.js, Express, and MongoDB API!"
}

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Notes:

If you need it, see Migrating from mLab to MongoDB Atlas.