├── .gitignore ├── README.md ├── gulpfile.js ├── package-lock.json ├── package.json ├── src ├── cats.js ├── client.jsx └── index.js └── webpack.config.js /.gitignore: -------------------------------------------------------------------------------- 1 | node_modules/ 2 | lib/ 3 | dist/ 4 | npm-debug.log 5 | .DS_Store 6 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # Intro to React 2 | 3 | Quick intro to [React](https://reactjs.org/). 4 | 5 | ### Contents 6 | 7 | 1. [What is React?](https://github.com/mjhea0/react-intro#what-is-react) 8 | 1. [Project setup](https://github.com/mjhea0/react-intro#project-setup) 9 | 1. [Lint the code](https://github.com/mjhea0/react-intro#lint-the-code) 10 | 1. [Add a cat](https://github.com/mjhea0/react-intro#add-a-cat) 11 | 1. [React setup](https://github.com/mjhea0/react-intro#react-setup) 12 | 1. [Webpack setup](https://github.com/mjhea0/react-intro#webpack-setup) 13 | 14 | ### Objectives 15 | 16 | By the end of this tutorial, you should be able to: 17 | 18 | 1. Explain what React is and how it compares to Angular and Vue 19 | 1. Set up a modern React environment with Babel and Webpack 20 | 1. Create and render a React component in the browser 21 | 22 | ## What is React? 23 | 24 | > YOUR TURN: What is React? How does it compare to Angular and Vue? 25 | 26 | ## Project setup 27 | 28 | Create a new project directory: 29 | 30 | ```sh 31 | $ mkdir react-intro 32 | $ cd react-intro 33 | $ npm init -y 34 | ``` 35 | 36 | Install gulp and babel: 37 | 38 | ```sh 39 | $ npm install --save-dev gulp@4.0.2 gulp-babel@8.0.0 @babel/core@7.21.0 @babel/preset-env@7.20.2 40 | ``` 41 | 42 | > YOUR TURN: What's babel? What does `@babel/preset-env` do? 43 | 44 | 45 | Create a *gulpfile.js* file in the project root: 46 | 47 | ```javascript 48 | const gulp = require('gulp'); 49 | const babel = require('gulp-babel'); 50 | 51 | gulp.task('build', (done) => { 52 | gulp.src(['src/**/*.js']) 53 | .pipe(babel({ presets: ['@babel/preset-env'] })) 54 | .pipe(gulp.dest('lib')); 55 | done(); 56 | }); 57 | ``` 58 | 59 | Now add a "src" and "lib" folder, and then add an *index.js* file to the "src" to test babel: 60 | 61 | ```javascript 62 | console.log('hello, world!'); 63 | ``` 64 | 65 | Finally, add a `start` script to *package.json*: 66 | 67 | ```json 68 | "scripts": { 69 | "start": "gulp build && node lib/index.js" 70 | }, 71 | ``` 72 | 73 | Sanity Check: 74 | 75 | ```sh 76 | $ npm start 77 | 78 | > react-intro@0.0.0 start /react-intro 79 | > gulp build && node lib/index.js 80 | 81 | [18:00:21] Using gulpfile ~/react-intro/gulpfile.js 82 | [18:00:21] Starting 'build'... 83 | [18:00:22] Finished 'build' after 361 ms 84 | hello, world! 85 | ``` 86 | 87 | > YOUR TURN: What happened? 88 | 89 | ## Lint the code 90 | 91 | Install: 92 | 93 | ```sh 94 | $ npm install --save-dev eslint@8.35.0 eslint-config-airbnb@18.2.1 95 | $ npm install --save-dev eslint-plugin-import@2.27.5 eslint-plugin-jsx-a11y@6.7.1 96 | $ npm install --save-dev eslint-plugin-react@7.32.2 gulp-eslint@6.0.0 97 | ``` 98 | 99 | > YOUR TURN: Why lint? What do those packages do? 100 | 101 | Add the config to *package.json*: 102 | 103 | ```json 104 | "eslintConfig": { 105 | "extends": "airbnb", 106 | "plugins": [ 107 | "import" 108 | ] 109 | }, 110 | ``` 111 | 112 | Update *gulpfile.js* with a new task: 113 | 114 | ```javascript 115 | gulp.task('lint', (done) => { 116 | gulp.src([ 117 | 'gulpfile.js', 118 | 'src/**/*.js', 119 | ]) 120 | .pipe(eslint()) 121 | .pipe(eslint.format()) 122 | .pipe(eslint.failAfterError()); 123 | done(); 124 | }); 125 | ``` 126 | 127 | Make sure to add the dependency: 128 | 129 | ```javascript 130 | const eslint = require('gulp-eslint'); 131 | ``` 132 | 133 | Then add the `lint` task to the `build`: 134 | 135 | ```javascript 136 | gulp.task('build', gulp.series('lint', (done) => { 137 | gulp.src(['src/**/*.js']) 138 | .pipe(babel({ presets: ['@babel/preset-env'] })) 139 | .pipe(gulp.dest('lib')); 140 | done(); 141 | })); 142 | ``` 143 | 144 | Run the linter: 145 | 146 | ```sh 147 | $ npm start 148 | ``` 149 | 150 | You should see a warning: 151 | 152 | ```sh 153 | /react-intro/src/index.js 154 | 1:1 warning Unexpected console statement no-console 155 | 156 | ✖ 1 problem (0 errors, 1 warning) 157 | ``` 158 | 159 | Ignore it. 160 | 161 | > YOUR TURN: Why are we ignoring it? 162 | 163 | ## Add a cat 164 | 165 | Within "src" add a new file called *cats.js*: 166 | 167 | ```javascript 168 | class Cat { 169 | constructor(name) { 170 | this.name = name; 171 | } 172 | 173 | meow() { 174 | return `Meow meow, I am ${this.name}`; 175 | } 176 | } 177 | 178 | module.exports = Cat; 179 | ``` 180 | 181 | Update *index.js*: 182 | 183 | ```javascript 184 | const Cat = require('./cats'); 185 | 186 | const toby = new Cat('Toby'); 187 | console.log(toby.meow()); 188 | ``` 189 | 190 | Run `npm start`: 191 | 192 | ```sh 193 | Meow meow, I am Toby 194 | ``` 195 | 196 | > YOUR TURN: What's happening here? 197 | 198 | ## React setup 199 | 200 | Install: 201 | 202 | ```sh 203 | $ npm install --save react@18.2.0 react-dom@18.2.0 prop-types@15.8.1 204 | ``` 205 | 206 | > YOUR TURN: What's React DOM? 207 | 208 | Then add a "dist" folder with an *index.html* file: 209 | 210 | ```html 211 | 212 | 213 | 214 | React Intro 215 | 216 | 217 | 218 | 219 | 220 | ``` 221 | 222 | > YOUR TURN: What's bundle.js? 223 | 224 | Add a `div` to the *index.html* file, just above the `script` tag: 225 | 226 | ```html 227 |
228 | ``` 229 | 230 | Create a new file in "src" called *client.jsx*: 231 | 232 | ```javascript 233 | import React from 'react'; 234 | import ReactDOM from 'react-dom'; 235 | import PropTypes from 'prop-types'; 236 | import Cat from './cats'; 237 | 238 | const catMeow = new Cat('Browser Cat').meow(); 239 | 240 | const App = (props) => { 241 | const { message } = props; 242 | return ( 243 |
244 | The cat says:  245 | { message } 246 |
247 | ); 248 | }; 249 | 250 | App.propTypes = { 251 | message: PropTypes.string.isRequired, 252 | }; 253 | 254 | ReactDOM.render(, document.querySelector('.app')); 255 | ``` 256 | 257 | > YOUR TURN: Is that HTML in a JS file? Why? What's JSX? Also, what does @babel/preset-react do? 258 | 259 | To process the *.jsx* file, install: 260 | 261 | ```sh 262 | $ npm install --save-dev @babel/preset-react@7.18.6 263 | ``` 264 | 265 | Add the preset to the `build` task in *gulpfile.js*: 266 | 267 | ```javascript 268 | gulp.task('build', gulp.series('lint', (done) => { 269 | gulp.src(['src/**/*.js']) 270 | .pipe(babel({ presets: ['@babel/preset-env', '@babel/preset-react'] })) 271 | .pipe(gulp.dest('lib')); 272 | done(); 273 | })); 274 | ``` 275 | 276 | Finally, update the `lint` task to handle *.jsx* files: 277 | 278 | ```javascript 279 | gulp.task('lint', (done) => { 280 | gulp.src([ 281 | 'gulpfile.js', 282 | 'src/**/*.js', 283 | 'src/**/*.jsx', 284 | ]) 285 | .pipe(eslint()) 286 | .pipe(eslint.format()) 287 | .pipe(eslint.failAfterError()); 288 | done(); 289 | }); 290 | ``` 291 | 292 | Run the linter: 293 | 294 | ```sh 295 | $ ./node_modules/.bin/gulp lint 296 | ``` 297 | 298 | You should see the following error: 299 | 300 | ```sh 301 | /react-intro/src/client.jsx 302 | 22:44 error 'document' is not defined no-undef 303 | ``` 304 | 305 | > YOUR TURN: Why did we get this error? 306 | 307 | To correct this, update the `eslintConfig` in *package.json*: 308 | 309 | ```javascript 310 | "eslintConfig": { 311 | "extends": "airbnb", 312 | "plugins": [ 313 | "import" 314 | ], 315 | "env": { 316 | "browser": true 317 | } 318 | }, 319 | ``` 320 | 321 | ## Webpack setup 322 | 323 | Install: 324 | 325 | ```sh 326 | $ npm install --save-dev webpack@5.75.0 webpack-cli@5.0.1 babel-loader@9.1.2 ajv@8.12.0 327 | ``` 328 | 329 | > YOUR TURN: What's webpack? What does babel-loader do? Why all these damn tools?!?! 330 | 331 | Then add *webpack.config.js* to the project root: 332 | 333 | ```javascript 334 | const path = require('path'); 335 | 336 | module.exports = { 337 | mode: 'development', 338 | entry: './src/client.jsx', 339 | output: { 340 | path: path.resolve(__dirname, 'dist'), 341 | filename: 'bundle.js', 342 | }, 343 | module: { 344 | rules: [ 345 | { 346 | test: /\.jsx?$/, 347 | exclude: /node_modules/, 348 | use: [ 349 | { 350 | loader: 'babel-loader', 351 | options: { 352 | presets: [ 353 | '@babel/preset-env', 354 | '@babel/preset-react', 355 | ] 356 | }, 357 | }, 358 | ], 359 | }, 360 | ], 361 | }, 362 | resolve: { 363 | extensions: ['*', '.js', '.jsx'], 364 | }, 365 | } 366 | ``` 367 | 368 | Update the `start` script in *package.json*: 369 | 370 | ```json 371 | "start": "gulp lint && webpack" 372 | ``` 373 | 374 | Run: 375 | 376 | ```sh 377 | $ npm start 378 | ``` 379 | 380 | Then open the *index.html* file within "dist" in your browser. You should see: 381 | 382 | ``` 383 | The cat says: Meow meow, I am Browser Cat 384 | ``` 385 | -------------------------------------------------------------------------------- /gulpfile.js: -------------------------------------------------------------------------------- 1 | const gulp = require('gulp'); 2 | const babel = require('gulp-babel'); 3 | const eslint = require('gulp-eslint'); 4 | 5 | gulp.task('lint', (done) => { 6 | gulp.src([ 7 | 'gulpfile.js', 8 | 'src/**/*.js', 9 | 'src/**/*.jsx', 10 | ]) 11 | .pipe(eslint()) 12 | .pipe(eslint.format()) 13 | .pipe(eslint.failAfterError()); 14 | done(); 15 | }); 16 | 17 | gulp.task('build', gulp.series('lint', (done) => { 18 | gulp.src(['src/**/*.js']) 19 | .pipe(babel({ presets: ['@babel/preset-env', '@babel/preset-react'] })) 20 | .pipe(gulp.dest('lib')); 21 | done(); 22 | })); 23 | -------------------------------------------------------------------------------- /package.json: -------------------------------------------------------------------------------- 1 | { 2 | "name": "react-intro", 3 | "version": "1.0.0", 4 | "description": "Quick intro to [React](https://reactjs.org/).", 5 | "main": "index.js", 6 | "scripts": { 7 | "start": "gulp lint && webpack" 8 | }, 9 | "repository": { 10 | "type": "git", 11 | "url": "git+https://github.com/mjhea0/react-intro.git" 12 | }, 13 | "keywords": [], 14 | "author": "", 15 | "license": "ISC", 16 | "bugs": { 17 | "url": "https://github.com/mjhea0/react-intro/issues" 18 | }, 19 | "homepage": "https://github.com/mjhea0/react-intro#readme", 20 | "devDependencies": { 21 | "@babel/core": "^7.21.0", 22 | "@babel/preset-env": "^7.20.2", 23 | "@babel/preset-react": "^7.18.6", 24 | "ajv": "^8.12.0", 25 | "babel-loader": "^9.1.2", 26 | "eslint": "^8.35.0", 27 | "eslint-config-airbnb": "^18.2.1", 28 | "eslint-plugin-import": "^2.27.5", 29 | "eslint-plugin-jsx-a11y": "^6.7.1", 30 | "eslint-plugin-react": "^7.32.2", 31 | "gulp": "^4.0.2", 32 | "gulp-babel": "^8.0.0", 33 | "gulp-eslint": "^6.0.0", 34 | "webpack": "^5.75.0", 35 | "webpack-cli": "^5.0.1" 36 | }, 37 | "eslintConfig": { 38 | "extends": "airbnb", 39 | "plugins": [ 40 | "import" 41 | ], 42 | "env": { 43 | "browser": true 44 | } 45 | }, 46 | "dependencies": { 47 | "prop-types": "^15.8.1", 48 | "react": "^18.2.0", 49 | "react-dom": "^18.2.0" 50 | } 51 | } 52 | -------------------------------------------------------------------------------- /src/cats.js: -------------------------------------------------------------------------------- 1 | class Cat { 2 | constructor(name) { 3 | this.name = name; 4 | } 5 | 6 | meow() { 7 | return `Meow meow, I am ${this.name}`; 8 | } 9 | } 10 | 11 | module.exports = Cat; 12 | -------------------------------------------------------------------------------- /src/client.jsx: -------------------------------------------------------------------------------- 1 | import React from 'react'; 2 | import ReactDOM from 'react-dom'; 3 | import PropTypes from 'prop-types'; 4 | import Cat from './cats'; 5 | 6 | const catMeow = new Cat('Browser Cat').meow(); 7 | 8 | const App = (props) => { 9 | const { message } = props; 10 | return ( 11 |
12 | The cat says:  13 | { message } 14 |
15 | ); 16 | }; 17 | 18 | App.propTypes = { 19 | message: PropTypes.string.isRequired, 20 | }; 21 | 22 | ReactDOM.render(, document.querySelector('.app')); 23 | -------------------------------------------------------------------------------- /src/index.js: -------------------------------------------------------------------------------- 1 | const Cat = require('./cats'); 2 | 3 | const toby = new Cat('Toby'); 4 | console.log(toby.meow()); 5 | -------------------------------------------------------------------------------- /webpack.config.js: -------------------------------------------------------------------------------- 1 | const path = require('path'); 2 | 3 | module.exports = { 4 | mode: 'development', 5 | entry: './src/client.jsx', 6 | output: { 7 | path: path.resolve(__dirname, 'dist'), 8 | filename: 'bundle.js', 9 | }, 10 | module: { 11 | rules: [ 12 | { 13 | test: /\.jsx?$/, 14 | exclude: /node_modules/, 15 | use: [ 16 | { 17 | loader: 'babel-loader', 18 | options: { 19 | presets: [ 20 | '@babel/preset-env', 21 | '@babel/preset-react', 22 | ] 23 | }, 24 | }, 25 | ], 26 | }, 27 | ], 28 | }, 29 | resolve: { 30 | extensions: ['*', '.js', '.jsx'], 31 | }, 32 | } 33 | --------------------------------------------------------------------------------