RESTful API Node Server

Installation

Install frontend project (for docker-compose orchestration):

git submodule update --init --recursive

Install the dependencies:

yarn install

Set the environment variables:

cp .env.example .env

# open .env and modify the environment variables (if needed)

Running locally:

yarn docker:dev

Running migrations:

After running docker you have to make sure that the migrations are run otherwise the data for services won't be there, running

./node_modules/.bin/migrate up --md migrations

Make sure to SELECT the migration with SPACE_BAR key and then hit enter.

Open up the app in the Browser

Navigate to http://localhost:3001

Testing:

Have in mind that for running test the project must be running as some of them use the database (integration tests).

# run all tests
yarn test

# run all tests in watch mode
yarn test:watch

# run test coverage
yarn coverage

Linting:

# run ESLint
yarn lint

# fix ESLint errors
yarn lint:fix

# run prettier
yarn prettier

# fix prettier errors
yarn prettier:fix

Environment Variables

The environment variables can be found and modified in the .env file. They come with these default values:

# Port number
PORT=3000

# URL of the Mongo DB
MONGODB_URL=mongodb://127.0.0.1:27017/test-assessment-db

MIGRATE_dbConnectionUri=mongodb://127.0.0.1:27017/test-assessment-db

NODE_ENV=development

Project Structure

src\
 |--config\         # Environment variables and configuration related things
 |--controllers\    # Route controllers (controller layer)
 |--docs\           # Swagger files
 |--middlewares\    # Custom express middlewares
 |--models\         # Mongoose models (data layer)
 |--routes\         # Routes
 |--services\       # Business logic (service layer)
 |--utils\          # Utility classes and functions
 |--validations\    # Request data validation schemas
 |--app.js          # Express app
 |--index.js        # App entry point

API Documentation

To view the list of available APIs and their specifications, run the server and go to http://localhost:3000/v1/docs in your browser. This documentation page is automatically generated using the swagger definitions written as comments in the route files.

Error Handling

The app has a centralized error handling mechanism.

Controllers should try to catch the errors and forward them to the error handling middleware (by calling next(error)). For convenience, you can also wrap the controller inside the catchAsync utility wrapper, which forwards the error.

const catchAsync = require('../utils/catchAsync');

const controller = catchAsync(async (req, res) => {
  // this error will be forwarded to the error handling middleware
  throw new Error('Something wrong happened');
});

The error handling middleware sends an error response, which has the following format:

{
  "code": 404,
  "message": "Not found"
}

When running in development mode, the error response also contains the error stack.

The app has a utility ApiError class to which you can attach a response code and a message, and then throw it from anywhere (catchAsync will catch it).

For example, if you are trying to get a user from the DB who is not found, and you want to send a 404 error, the code should look something like:

const httpStatus = require('http-status');
const ApiError = require('../utils/ApiError');
const User = require('../models/User');

const getUser = async (userId) => {
  const user = await User.findById(userId);
  if (!user) {
    throw new ApiError(httpStatus.NOT_FOUND, 'User not found');
  }
};

Logging

Import the logger from src/config/logger.js. It is using the Winston logging library.

Logging should be done according to the following severity levels (ascending order from most important to least important):

const logger = require('<path to src>/config/logger');

logger.error('message'); // level 0
logger.warn('message'); // level 1
logger.info('message'); // level 2
logger.http('message'); // level 3
logger.verbose('message'); // level 4
logger.debug('message'); // level 5

In development mode, log messages of all severity levels will be printed to the console.

In production mode, only info, warn, and error logs will be printed to the console.
It is up to the server (or process manager) to actually read them from the console and store them in log files.
This app uses pm2 in production mode, which is already configured to store the logs in log files.

Note: API request information (request url, response code, timestamp, etc.) are also automatically logged (using morgan).

Custom Mongoose Plugins

The app also contains 2 custom mongoose plugins that you can attach to any mongoose model schema. You can find the plugins in src/models/plugins.

const mongoose = require('mongoose');
const { toJSON, paginate } = require('./plugins');

const userSchema = mongoose.Schema(
  {
    /* schema definition here */
  },
  { timestamps: true }
);

userSchema.plugin(toJSON);
userSchema.plugin(paginate);

const User = mongoose.model('User', userSchema);

toJSON

The toJSON plugin applies the following changes in the toJSON transform call:

• removes __v, createdAt, updatedAt, and any schema path that has private: true
• replaces _id with id

paginate

The paginate plugin adds the paginate static method to the mongoose schema.

Adding this plugin to the User model schema will allow you to do the following:

const queryUsers = async (filter, options) => {
  const users = await User.paginate(filter, options);
  return users;
};

The filter param is a regular mongo filter.

The options param can have the following (optional) fields:

const options = {
  sortBy: 'name:desc', // sort order
  limit: 5, // maximum results per page
  page: 2, // page number
};

The plugin also supports sorting by multiple criteria (separated by a comma): sortBy: name:desc,role:asc

The paginate method returns a Promise, which fulfills with an object having the following properties:

{
  "results": [],
  "page": 2,
  "limit": 5,
  "totalPages": 10,
  "totalResults": 48
}

Linting

Linting is done using ESLint and Prettier.

In this app, ESLint is configured to follow the Airbnb JavaScript style guide with some modifications. It also extends eslint-config-prettier to turn off all rules that are unnecessary or might conflict with Prettier.

To modify the ESLint configuration, update the .eslintrc.json file. To modify the Prettier configuration, update the .prettierrc.json file.

To prevent a certain file or directory from being linted, add it to .eslintignore and .prettierignore.

To maintain a consistent coding style across different IDEs, the project contains .editorconfig

MIT