[comment]: # "markdown: { smartypants: true }" ### Navigating # Node.js #### in 2022 <small>a (very opinionated) beginner's guide</small>

 AJ ONeal <br> [@\_beyondcode](https://twitter.com/@_beyondcode) <br> [twitch.tv/coolaj86](https://twitch.tv/coolaj86)

Technophobic Technologist Dangerous Wrong Thinker Equal Opportunity Offender

<img title="node.js: official logo" src="https://nodejs.org/static/images/logos/nodejs-new-pantone-black.svg" width="60%" /> https://nodejs.org/en/about/resources/

<img title="node.js: an absolute dumpster fire" src="https://i.imgur.com/OlolkHa.png" width=70% />



1. Why Node.js? 2. Install 3. Tools 4. Hello World 5. Web Server

When there's _great_ options out there...

<img title="Go: logo" src="https://user-images.githubusercontent.com/727262/40395108-6bcc327a-5e1e-11e8-9f76-3917983b8563.png" width="30%"/><img src="https://raw.githubusercontent.com/keygx/Go-gopher-Vector/fe01b920482f9ab2c6ec7d1928c3c617341e3841/svg/gopher03c.svg" title="Golang Gopher" width="20%" /> <small><a href="https://go.dev/blog/go-brand">https://go.dev/blog/go-brand</a><br><a href="https://go.dev/blog/gopher">https://go.dev/blog/gopher</a></small>

 <img title="happy ferris" src="https://rustacean.net/assets/rustacean-flat-happy.png" width="30%"/> <small><a href="https://github.com/rust-lang/rust/issues/11562">https://github.com/rust-lang/rust/issues/11562</a><br><a href="https://rustacean.net/">https://rustacean.net/</a></small>

# 1. Why Node.js?

> "You're not paid to (ab)use _every_ feature of a language. > > You're paid to write _correct_ programs." ~ Douglas Crockford

### It is _possible_ ### to be # good ### at JavaScript

> "Perfection is achieved not when there is nothing more to add, > but when there is nothing left to take away" ~ Antoine de Saint-Exupery

# less ### is # more

# Benefits

- **Single-Threaded Execution** \ (no data races, like Rust) <br>

- **Event-Oriented** \ (high concurrency, like Go) <br>

- **Modern ALL-the-THINGS** \ (functional, duck-typed, pure-objects)

It's great for web services. ```js let server = express(); let app = Router(); server.use("/", app); Http.createServer(server).listen(3000); ``` <small><a href="https://www.npmjs.com/package/@root/async-router">https://www.npmjs.com/package/@root/async-router</a></small>

And quite usable for command line utilities. ```js let { $, question, sleep } = await import("zx"); await $`ls -lah`; ``` <small><a href="https://github.com/google/zx">https://github.com/google/zx</a></small>

...

it's there <small>a lot</small>

# Demerits

- **Too Much Legacy** \ (dumpster fire) <br>

- **No Cohesion** \ (too many cooks) <br>

...

- **Really, REALLY Bad Docs** \ (80/20 gone wrong)

Hold my MtnDew... <img title="AJ with pink heart sunglasses" src="https://i.imgur.com/HPCzpnY.png" width="50%" />

# 2. Install

<img title="node.js ALL downloads" src="https://i.imgur.com/2Jw7pPc.png" width="80%" />

<img title="node.js BAD downloads" src="https://i.imgur.com/2kQ1Cne.png" width="80%" />

## `sudo` <img title="sudo make me a sandwich" src="https://imgs.xkcd.com/comics/sandwich.png" width="37%" /> is _NOT_ your friend

<img title="node.js good downloads" src="https://i.imgur.com/AgWKZFu.png" width="80%" />

## `PATH` is _NOT_ your friend

(and neither is `brew`)

`webi` is your friend 

<img title="node.js good downloads" src="https://i.imgur.com/AgWKZFu.png" width="80%" />

- fastest (download) - fastest (setup) - conflict-free

and easy to remember ```sh curl "https://webinstall.dev" | bash webi node@lts ```

`+` cheat sheet ```bash webi node@latest ``` ```js let Http = require("http"); let app = function (req, res) { res.end("Hello, World!"); }; Http.createServer(app).listen(8080, function () { console.info("Listening on", this.address()); }); ```

# 3. Tools

Your brain is small.

And you suck at code.

(because you are human)

...

> "11 out of 10 dentists agree: > typing is the leading cause of typos" ~ ADA

# Tools 0. vim-essentials 1. prettier 2. jshint (or eslint) 3. jsdoc 4. tsc

## vim-essentials ```bash webi vim-essenntials ``` <https://webinstall.dev/vim-essentials>

## vim learn how to use the computer already

(are you back-end or not?)

## VS Code an acceptable alternative

### Spot Check How beginner are we?

- functions - events - primitives - variables - Promises - RegExp

- require - process - module scope - Fs - Buffer

## Prettier <https://prettier.io/docs/en/rationale.html>

0 BS

## Prettier ```bash webi prettier ``` ```bash npm install -g prettier ```

## Prettier `package.json`: ```bash { "scripts": { "prettier": "npx prettier@2.x -w '**/*.{md,js,html,css}'" } } ``` ```bash npm run prettier ```

## jshint <https://jshint.com/about/>

> "jslint has taught me more than I ever taught it" ~ Douglas Crockford

## jshint ```bash webi jshint ``` ```bash npm install -g jshint ```

## jshint `package.json`: ```json { "scripts": { "lint": "npx jshint@2.x -c ./.jshintrc *.js */*.js" } } ``` ```bash npm run lint ```

## vs eslint also good, but not as simple

## jsdoc ```bash npm install -g jsdoc ``` (for type hinting)

## jsdoc ```js /** * Starts the important thing with the stuff * @namespace Service * @param {Object} opts - all of the options * @param {String} opts.units - either 'meters' or 'feet' * @returns {Promise<Number>} - the process id */ Service.start = async function (opts) { // ... }; ```

## jsdoc `package.json`: ```json { "scripts": { "doc": "npx jsdoc@3.x --configure ./jsdoc.conf.json --destination ./docs --package ./package.json --readme ./README.md --access all --private --recurse ./index.js ./lib/" } } ``` ```bash npm run doc ```

## tsc ```bash npm install -g typescript ``` (for type hinting)

```js let answer = "Hello, World!"; answer = 42; // ❌ number is not a string ```

```js let Widget = require("widget"); Widget.getGizmo(); // ❌ did you mean getGadget()? ```

<img title="type hinting in javascript" src="https://user-images.githubusercontent.com/122831/130662033-d730d789-93b3-44b3-87fd-360b1168a634.jpg" width="80%" /> <small><a href="https://github.com/BeyondCodeBootcamp/jsdoc-typescript-starter">https://github.com/BeyondCodeBootcamp/jsdoc-typescript-starter</a></small>

# et cetera <https://webinstall.dev/>

## Why not Co-Pilot? <img title="octo-co-pilot" src="https://i.imgur.com/Gm8JRzH.png" width="60%" />

# 🚽

<small>(you'll write enough bad code all on your own)</small>

## 4. Hello World ```js console.info("Hello, World!"); ```

<small>(console.log is for burning)</small>

A better hello world... - a useful function - a unit test - an export - an import - a package

```js function greet(person) { return `Hello, ${person.name}!`; } ``` ❌ not useful

`messenger.js` ```js "use strict"; let Messenger = module.exports; ```

`module` `module.exports`

(🤯 don't overwrite `module.exports`!)

```js Messenger.parseEmails = function (text) { let emailRe = /[\w\.+-]+@[a-z][0-9a-z-\.]+[a-z]/gi; let emails = {}; for (;;) { let m = emailRe.exec(text); if (!m) { break; } let email = m[0].toLowerCase(); emails[email] = true; } return Object.keys(emails); }; ``` just trust me...

```js regexp.exec; ``` ```js for (;;) ``` ```js Object.keys; ```

Some sample input... ```txt Hello, my email is coolaj86@gmail.com. I like long messages from walks@beach.co coolaj86+node.js@gmail.com is an alias of mine. ```

A little self-test... ```js if (require.main === module) { let Assert = require("assert"); let text = ` Hello, my email is coolaj86@gmail.com. I like long messages from walks@beach.co `; let expected = "coolaj86@gmail.com,walks@beach.co,coolaj86+node.js@gmail.com"; let emails = Messenger.parseEmails(text).join(","); Assert.equal(expected, emails); console.info("Pass"); // ✅ "Pass" } ```

```js require; ``` ```js require.main; ``` ```js Assert; ```

how to use in multiple files?

`bin/parse-emails.js` ```js #!/usr/bin/env node "use strict"; let Messenger = require("./messenger.js"); let text = process.argv.slice(2).join(" "); let emails = Messenger.parseEmails(text); emails.forEach(function (email) { console.info(email); }); ``` ```bash chmod a+x bin/parse-emails.js ln -s parse-emails.js bin/parse-emails ```

```js #!/usr/bin/env node ``` ```js chmod; ``` ```js ln - s; ```

How to share with others?

## npm <img title="getting started with npm" src="https://i.imgur.com/ZTwFsAL.png" width="80%" /> <small><a href="https://i.imgur.com/ZTwFsAL.png">https://gist.github.com/coolaj86/1318304</a></small>

```bash npm config set init.author.email "you@example.com" ``` ```bash npm adduser ``` ```bash npm publish --access=public @YOUR_NAME/messenger ```

## 5. SaaS-ify

`server.js` ```js let Http = require("http"); let httpServer = require("http").createServer(app); httpServer.listen(3000, function () { console.info("Listening on", httpServer.address()); }); ```

```js function app(req, res) { let text = ""; req.on("readable", function () { for (;;) { let chunk = req.read()?.toString("utf8"); if (!chunk) { break; } text += chunk; } }); req.on("end", function () { let emails = Messenger.parseEmails(text).join(","); res.end(emails); }); }); ```

```js Http.createServer(app); ``` ```js req.on("readable"); ```

```bash npm run start ```

# Bonus Round

## telebit <img title="telebit explainer" src="https://i.imgur.com/nCx70uV.png" width="80%" />

## caddy + duckdns ```caddy example.duckdns.org { tls { dns duckdns xxxxxxxx-xxxx-4xxx-8xxx-xxxxxxxxxxxx } log { output stdout format console } reverse_proxy /api/* localhost:3000 root * /srv/example.com/public/ file_server } ```

> "if you use all of your intelligence to build the most complex thing you can, given there's a defect in there, by definition it's more complex than you can understand" ~ [Darryl Spencer](https://www.youtube.com/watch?v=OYMk4Zws-jE&t=3732s) ~ [Darryl Spencer](https://www.youtube.com/watch?v=OYMk4Zws-jE&t=3732s)