NodeJS Utils

This package provides a several set of tools, libraries or utilities that I use in my projects as well as in the @sergiogc9/nodejs-server package.

Table of Contents

• Table of Contents
• Getting started
  • Available modules
    • API
    • Log
    • Auth
    • Cache
    • Pushover

Getting started

You can get everything importing the whole package or import only some available sub-modules. To install the package:

yarn add -S @sergiogc9/nodejs-server or npm install --save @sergiogc9/nodejs-server

Available modules

API

This module contains some methods, middleware and constants to be used in your API controllers using express:

• Constants can be used to keep same response codes or errors between different APIs. Available constants:

  SERVER_ERROR, OPENAPI_VALIDATION_ERROR and NOT_FOUND_ERROR.

• Methods exported by the API module:

  successResponse(req, res, data, status = 200):

  Sends a success response through the passed response (res). It returns a JSON with the following keys:

  request: An object containing some request data as the body, method, path, parameters, body, etc.

  response: The data to send. It can be any JSON serializable data.

  status: The response status. By default is 200.

  time: The execution time. Only appears if the request has a Date startTime property added using a middleware as @sergiogc9/nodejs-server does.

  errorResponse(req, res, data, status):

  Sends an error response through the passed response (res). It behaves the same as the method successResponse with these differences:

  • There is not a default status, hence it is required.
  • The data returned is done through an error key instead of response.

• The middlewares available are:

  expressAsyncHandler:

  An express middleware to use an async function inside a controller.

Example usage:

import { RequestHandler, Router } from 'express';
import { expressAsyncHandler, errorResponse, successResponse, SERVER_ERROR } from '@sergiogc9/nodejs-utils/Api';

import User from 'models/User';

class UserController {
	public static list: RequestHandler = async (req, res) => {
		try {
			const users = await User.find();
			successResponse(req, res, users);
		} catch (e) {
			errorResponse(req, res, SERVER_ERROR, 500);
		}
	};
}

const router = Router();
router.get('/team', expressAsyncHandler(UserController.list));

Log

A helper utility to more fancy logs. It creates a .logs directory inside the project root and creates a log file per each day.

It generate logs using the following format:

[DD/MM/YYYY HH:MM] [PROCESS_ID] [PREFIX] [TYPE] Text

Example:

[03/02/2021 17:33] [MASTER] [API] [INFO] Booting the 'Time' middleware..

From left to right:

• Date: The date and time when the log was added.
• Process id: If using cluster, it shows the pid of the process. If not using the cluster api or the log comes from the master process, MASTER is shown.
• Prefix: You can create a custom Log instance with a prefix (see example below). If a prefix is set, the prefix name is shown.
• Type: The log type. It can be info, warn, error or a custom one.
• Text: The message to log.

The Log module exports by default a singleton instance ready to be used. If you want a custom Log with a custom prefix you can use the instance method initNewLog(prefix) or create a new Log instance passing the prefix in the constructor to Log class, which is named exported.

ℹ️ When using a custom prefix, all logs are also located in .logs/${prefix} directory.

Example using the default exported Log instance:

import log from '@sergiogc9/nodejs-utils/Log';

log.warn('Some warning message');

Example using a custom prefix:

import { Log } from '@sergiogc9/nodejs-utils/Log';

const log = new Log('api');
log.info("Booting the 'Time' middleware..");
log.custom('GENERAL', 'Some general message');

Auth

The Auth module contains some middleware and utils to easily add authentication into the server.

Available middlewares:

• httpAuthMiddleware:

  This middleware enables HTTP authentication. It needs a realm and an object containing the users and their password. The realm must be unique for each server and passwords must be hashed using SHA512:

  type HTTPAuthConfig = { realm: string; users: Record<string, string> };

  Enable HTTP authentication in all the server:

  import { httpAuthMiddleware } from '@sergiogc9/nodejs-utils/Auth';
  
  app.use(httpAuthMiddleware({ realm: '@sergiogc9/nodejs-utils', users: { user: 'SHA512 hash' } }));

  Enable HTTP authentication only for a specific route:

  import { httpAuthMiddleware } from '@sergiogc9/nodejs-utils/Auth';
  
  const authCredentials: HTTPAuthConfig = { realm: '@sergiogc9/nodejs-utils', users: { user: 'SHA512 hash' } };
  app.get('/auth', httpAuthMiddleware(authCredentials), expressAsyncHandler());

• authMiddleware:

  Middleware to easily validate the authentication using custom logic. Pass a function that receives the request and returns a boolean. The function can be async:

  import { AuthChecker, authMiddleware } from '@sergiogc9/nodejs-utils';
  
  const authChecker: AuthChecker = async req => {
  	const importantHeader = req.headers['important'];
  
  	const isValid = await validate(importantHeader);
  	return isValid;
  };
  
  const withAuth = authMiddleware(authChecker);
  
  app.get('/auth', withAuth, expressAsyncHandler());

• authBearerMiddleware:

  Same as authMiddleware middleware but in this case the function passed received the Bearer token.

  import { AuthBearerChecker, authBearerMiddleware } from '@sergiogc9/nodejs-utils';
  
  const authBearerChecker: AuthBearerChecker = async token => {
  	const isValid = await validate(token);
  	return isValid;
  };
  
  const withAuth = authBearerMiddleware(authBearerChecker);
  
  app.get('/auth', withAuth, expressAsyncHandler());

Cache

A cache middleware for express routes. It caches the response of a request by its originalUrl or url. It is based on memory-cache package.

Example of use:

import { Router } from 'express';
import Cache from '@sergiogc9/nodejs-utils/Cache';

const { cache } = Cache;
const router = Router();

// Cache response during 10 seconds
router.get('/', cache(10), HomeController.index);

Pushover

Static utility class that helps sending notifications using Pushover.

You only need to introduce the user config data once and then use the send static method. Example of use:

// Set user config data
Pushover.setUserConfig({
	user: 'user-id',
	token: 'app-token'
});
Pushover.send({ title: 'Wow!', message: 'Awesome message' });