Nodejs NPM
Table of Content
Introduction
npm is the world's largest software registry (npm docs). it consists of three major components:
- the website to discover packages, set up profiles, and manage other aspects of your npm experience.
- The CLI runs from a terminal, and is how most developers interact with npm.
- The registry is a large public database of JavaScript software and the meta-information surrounding it.
Common package configuration
package that gets used among projects
easy exporting and importing
To get a better importing experience of the common package
(import {requireAuth} from "@maguas/common"; instead of import requireAuth from "@maguas/common/src/requireAuth";)
the following is recommended:
- index.js with all files being exported
// Re-export stuff from errors and middlewares
export * from './errors/bad-request-error'
export * from './errors/custom-error'
export * from './errors/database-connection-error'
export * from './errors/not-authorized-error'
export * from './errors/not-found-error'
export * from './errors/request-validation-error'
export * from './middlewares/current-user'
export * from './middlewares/error-handler'
export * from './middlewares/require-auth'
export * from './middlewares/validate-request'
- add the main file property and the declarations property
{
"main": "./build/index.js",
"types": "./build/index.d.ts",
"files": [
"build/**/*"
]
}
- add this useful scripts to package.json
{
"scripts": {
"clean": "rimraf ./build",
"build": "npm run clean && tsc",
"pub": "git add . && git commit -m \"Updates\" && npm version patch && npm run build && npm publish --access public "
}
}
- set these properties in tsconfig.json
{
"declaration": true,
"outDir": "./build",
"esModuleInterop": true,
"skipLibCheck": true,
"forceConsistentCasingInFileNames": true
}
Favorite libraries
LERNA
A tool for managing JavaScript projects with multiple packages. lerna docs
lerna.json
{
"name": "root",
"private": true,
"devDependencies": {
"lerna": "^4.0.0"
},
"scripts": {
"start": "lerna run start --parallel"
}
}
package.json
{
"name": "root",
"private": true,
"devDependencies": {
"lerna": "^4.0.0"
},
"scripts": {
"start": "lerna run start --parallel"
}
}
PM2
PM2 is daemon process manager that will help you manage and keep
your application online. Getting started with PM2
is straightforward, it is offered as a simple
and intuitive CLI, installable via NPM. (pm2 docs)
- command used for executing a npm script
pm2 start npm --name "{app_name}" -- run {script_name}
- command to log any pm2 application running
pm2 logs
- command to monitor an application (memory usage)
pm2 monit
Commander
Here is an example of how to use commander
package.json
{
"name": "@maguas/jsnote",
"version": "1.0.0",
"description": "",
"scripts": {
"start": "tsc --watch --preserveWatchOutput",
"test": "echo \"Error: no test specified\" && exit 1",
"prepublishOnly": "esbuild src/index.ts --platform=node --outfile=dist/index.js --bundle --minify --define:process.env.NODE_ENV=\\\"production\\\""
},
"files": [
"dist"
],
"bin": "dist/index.js",
"publishConfig": {
"access": "public"
},
"keywords": [],
"author": "",
"license": "ISC",
"dependencies": {
"@maguastupaguas/local-client": "^1.0.0"
},
"devDependencies": {
"@maguastupaguas/local-api": "^1.0.0",
"@types/node": "^14.14.31",
"commander": "^7.1.0",
"esbuild": "0.8.26",
"typescript": "^4.2.2"
}
}
tsconfig.json
{
"compilerOptions": {
"target": "es5",
"module": "commonjs",
"outDir": "./dist",
"strict": true,
"esModuleInterop": true,
"skipLibCheck": true,
"forceConsistentCasingInFileNames": true
}
}
#!/usr/bin/env node
import {program} from 'commander'
import {serveCommand} from "./commands/serve";
// comment
program
.addCommand(serveCommand)
program.parse(process.argv)
./src/commands/serve
import {Command} from "commander";
import path from "path";
import {serve} from "@maguastupaguas/local-api";
const isProduction = process.env.NODE_ENV === 'production'
export const serveCommand = new Command()
.command('serve [filename]')
.description('Open a file for edting')
.option('-p, --port <number>', 'port to run server on', '4005')
.action(async (filename = 'notebook.js', options: { port: string }) => {
try {
const dir = path.join(process.cwd(), path.dirname(filename))
await serve(parseInt(options.port), path.basename(filename), dir, !isProduction)
console.log(`Opened ${filename}, Navigate to http://localhost:${options.port} to edit the file.`)
} catch (err) {
if (err.code === 'EADDRINUSE') {
console.error('Port is in use. Try running on a different port.')
} else {
console.log('Here the problem', err.message)
}
process.exit(1)
}
})
@maguastupaguas/local-api serve index.ts
import express from 'express'
import {createProxyMiddleware} from "http-proxy-middleware";
import path from "path";
import {createCellsRouter} from "./routes/cells";
export const serve = (port: number, filename: string, dir: string, useProxy: boolean) => {
const app = express()
app.use(createCellsRouter(filename, dir))
if (useProxy){
app.use(createProxyMiddleware({
target: 'http://localhost:3000',
ws: true,
logLevel: 'silent'
}))
} else {
// WHY resolve???
const packagePath = require.resolve('@maguastupaguas/local-client/build/index.html')
app.use(express.static(path.dirname(packagePath)))
}
return new Promise<void>((resolve, reject) => {
app.listen(port, resolve).on('error', reject)
})
}
Concurrently
Run multiple commands concurrently. Like npm run watch-js & npm run watch-less but better. (concurrently docs)
{
"scripts": {
"start": "node index.js",
"server": "nodemon index.js",
"client": "npm run start --prefix client",
"dev": "concurrently \"npm run server\" \"npm run client\""
}
}
Ngrok
Ngrok exposes local servers behind NATs and firewalls to the public internet over secure tunnels. (ngrok docs)
Expose a web server on port 80 of your local machine to the internet
ngrok http 80