The Illustrated Guide to Node.js - KCDC 2023

Node.js is a compelling platform for building all types of applications for startups to enterprises. Node.js strategically unites developers through the universal language of JavaScript. Or TypeScript! Why should you learn Node.js, and where do you start?

You will walk away from this fun introduction to Node.js having learned its strengths and the tools you need to be productive. We will cover a typical workflow of creating and debugging a web application. We'll also look at popular frameworks, libraries, and learning resources to give you the best start.

Transcript

18. Why Node.js? • Rapid innovation & delivery • Developer happiness • Attract & retain talent • Performance “Why Node.js is Becoming the Go-To Technology in the Enterprise” – nearform.com
19. Why Node.js? productivity satisfaction performance lower costs Improved results year-over-year Node.js Foundation User Survey
23. • Backend API for SPAs, Mobile apps, etc. • “Serverless” computing • Real-time, streaming • WebSockets, push notifications • Chat, IM, social media Node.js Use Cases
24. More than just backend • Automation Scripts (DevOps) • CLI tools (compile with nexe) • Microservices • Internet of Things • Desktop Apps
25. Slack Visual Studio Code
27. DevOps • Small footprint • Cross-platform • Event-driven • OSS tools • Containers
34. Releases and Long-Term Support (LTS)
38. Install Node.js https://nodejs.org
39. Install Node.js with NVM Mac or Linux? Use nvm! https://github.com/nvm-sh/nvm Windows? Install Windows Subsytem for Linux (WSL)! > nvm install 18
40. Install Node.js with NVM https://github.com/coreybutler/nvm-windows > nvm install 18
41. What You Get > node –v v18.16.1 > npm –v 9.7.1
42. > node –v v18.16.1 > npm –v 9.7.1 What You Get
43. First Things First! > mkdir myproject > cd myproject > npm init This utility will walk you through creating a package.json file...
44. Install Dependencies > npm install axios > npm install --save-dev eslint > npm install -D eslint-config-reverentgeek
45. const fs = require( "fs" ); // Built-in Node.js module const express = require( "express" ); // Module installed via npm const ApiService = require( "./app/ApiService" ); // Local module const api = new ApiService( { port: 8888 } ); module-examples.js
46. const fs = require( "fs" ); // Built-in Node.js module const express = require( "express" ); // Module installed via npm const ApiService = require( "./app/ApiService" ); // Local module const api = new ApiService( { port: 8888 } ); module-examples.js
47. const fs = require( "fs" ); // Built-in Node.js module const express = require( "express" ); // Module installed via npm const ApiService = require( "./app/ApiService" ); // Local module const api = new ApiService( { port: 8888 } ); module-examples.js
48. const fs = require( "fs" ); // Built-in Node.js module const express = require( "express" ); // Module installed via npm const ApiService = require( "./app/ApiService" ); // Local module const api = new ApiService( { port: 8888 } ); module-examples.js
49. const fs = require( "fs" ); // Built-in Node.js module const express = require( "express" ); // Module installed via npm const ApiService = require( "./app/ApiService" ); // Local module const api = new ApiService( { port: 8888 } ); module-examples.js
50. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Traditional Node-style callback api.methodWithACallback( "bacon", 42, function( err, results ) { if ( err ) { // Do something with the error console.log( err ); return; } // Do stuff with results for ( let i = 0; i < results.length; i++ ) { // stuff... } } ); callback-example.js
51. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Traditional Node-style callback api.methodWithACallback( "bacon", 42, function( err, results ) { if ( err ) { // Do something with the error console.log( err ); return; } // Do stuff with results for ( let i = 0; i < results.length; i++ ) { // stuff... } } ); callback-example.js
52. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Traditional Node-style callback api.methodWithACallback( "bacon", 42, function( err, results ) { if ( err ) { // Do something with the error console.log( err ); return; } // Do stuff with results for ( let i = 0; i < results.length; i++ ) { // stuff... } } ); callback-example.js
53. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Promise-style callback api.methodReturningAPromise( "bacon", 42 ) .then( results => { for ( let i = 0; i < results.length; i++ ) { // stuff... } } ) .catch( err => { console.log( err ); } ); promise-example.js
54. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Promise-style callback api.methodReturningAPromise( "bacon", 42 ) .then( results => { for ( let i = 0; i < results.length; i++ ) { // stuff... } } ) .catch( err => { console.log( err ); } ); promise-example.js
55. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Promise-style callback api.methodReturningAPromise( "bacon", 42 ) .then( results => { for ( let i = 0; i < results.length; i++ ) { // stuff... } } ) .catch( err => { console.log( err ); } ); promise-example.js
56. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Promise-style callback api.methodReturningAPromise( "bacon", 42 ) .then( results => { for ( let i = 0; i < results.length; i++ ) { // stuff... } } ) .catch( err => { console.log( err ); } ); promise-example.js
57. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Async-await callback async function doTheThing() { try { const users = await api.asyncMethodReturningUsers(); const results = await api.methodReturningAPromise( "bacon", 42 ); for ( let i = 0; i < results.length; i++ ) { // stuff... } } catch( err ) { console.log( err ); } } doTheThing(); async-await-example.js
58. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Async-await callback async function doTheThing() { try { const users = await api.asyncMethodReturningUsers(); const results = await api.methodReturningAPromise( "bacon", 42 ); for ( let i = 0; i < results.length; i++ ) { // stuff... } } catch( err ) { console.log( err ); } } doTheThing(); async-await-example.js
59. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Async-await callback async function doTheThing() { try { const users = await api.asyncMethodReturningUsers(); const results = await api.methodReturningAPromise( "bacon", 42 ); for ( let i = 0; i < results.length; i++ ) { // stuff... } } catch( err ) { console.log( err ); } } doTheThing(); async-await-example.js
60. const ApiService = require( "./app/ApiService" ); const api = new ApiService( { port: 8888 } ); // Async-await callback async function doTheThing() { try { const users = await api.asyncMethodReturningUsers(); const results = await api.methodReturningAPromise( "bacon", 42 ); for ( let i = 0; i < results.length; i++ ) { // stuff... } } catch( err ) { console.log( err ); } } doTheThing(); async-await-example.js
61. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js
62. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js
63. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js
64. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js
65. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js const t = require( "./temperature" ); const c = t.boilingCelsius; const f = t.convertToFahrenheit( c ); console.log( `${ c } C is ${ f } F` ); // output: 100 C is 212 F temp-example.js
66. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js const t = require( "./temperature" ); const c = t.boilingCelsius; const f = t.convertToFahrenheit( c ); console.log( `${ c } C is ${ f } F` ); // output: 100 C is 212 F temp-example.js
67. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js const t = require( "./temperature" ); const c = t.boilingCelsius; const f = t.convertToFahrenheit( c ); console.log( `${ c } C is ${ f } F` ); // output: 100 C is 212 F temp-example.js
68. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js const t = require( "./temperature" ); const c = t.boilingCelsius; const f = t.convertToFahrenheit( c ); console.log( `${ c } C is ${ f } F` ); // output: 100 C is 212 F temp-example.js
69. function convertToCelsius( f ) { return ( f - 32 ) * ( 5 / 9 ); } function convertToFahrenheit( c ) { return ( c * ( 9 / 5 ) ) + 32; } const temp = { freezingCelsius: 0, freezingFahrenheit: 32, boilingCelsius: 100, boilingFahrenheit: 212, convertToCelsius, convertToFahrenheit }; module.exports = temp; temperature.js const t = require( "./temperature" ); const c = t.boilingCelsius; const f = t.convertToFahrenheit( c ); console.log( `${ c } C is ${ f } F` ); // output: 100 C is 212 F temp-example.js
70. import { readFile } from "node:fs/promises"; export async function readFileJson( fileName ) { const text = await readFile( fileName ); const data = JSON.parse( text ); return data; } esm-module-example.js
71. import { readFile } from "node:fs/promises"; export async function readFileJson( fileName ) { const text = await readFile( fileName ); const data = JSON.parse( text ); return data; } esm-module-example.js
72. import { readFile } from "node:fs/promises"; export async function readFileJson( fileName ) { const text = await readFile( fileName ); const data = JSON.parse( text ); return data; } esm-module-example.js
73. esm-module-example.js import { readFile } from "node:fs/promises"; export async function readFileJson( fileName ) { const text = await readFile( fileName ); const data = JSON.parse( text ); return data; } esm-example.js import { readFileJson } from "./esm-module-example.mjs"; const baconFile = new URL( "./bacon.json", import.meta.url ); const bacon = await readFileJson( baconFile ); console.log( bacon );
74. esm-module-example.js import { readFile } from "node:fs/promises"; export async function readFileJson( fileName ) { const text = await readFile( fileName ); const data = JSON.parse( text ); return data; } esm-example.js import { readFileJson } from "./esm-module-example.mjs"; const baconFile = new URL( "./bacon.json", import.meta.url ); const bacon = await readFileJson( baconFile ); console.log( bacon );
75. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
76. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
77. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
78. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
79. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
80. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
81. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
82. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { try { const pool = await sql.connect( cnx ); const result = await pool.request() .input( "email", sql.VarChar( 100 ), email ) .query( "select * from accounts where email = @email" ); return result; } catch ( err ) { // log error } } sql-example.js
83. const sql = require( "mssql" ); // Read from environment variables const cnx = process.env.SQL_CONNECTION; async function getAccountByEmail( email ) { ... } module.exports = { getAccountByEmail }; sql-example.js
87. Developer tools Package(s) Description eslint lint and format rules for JavaScript nodemon automatically restarts in dev node:test, jest, mocha test frameworks testdouble, sinon spies, stubs, mocks
88. Recommended tools Package(s) Description dotenv loads environment variables from a .env file fs-extra adds convenient extensions to file system fetch, axios, or got http clients socket.io sockets, real-time commander command-line argument library for building CLIs nexe compile app to a standalone executable
89. Frameworks • Express.js • Fastify • Nest.js • Electron.js
90. Integration Strategies • Node.js as proxy, use http client • nginx • Messaging (e.g. RabbitMQ, ZeroMQ Azure Service Bus)
91. https://bit.ly/node-crash-course