Quickstart Redux Create React App template

Opinionated quickstart Create React App (CRA) template with Redux, React Testing Library, eslint and stylelint configurations.

See full documentation.

Usage

npx create-react-app %PROJECT_NAME% --template quickstart-redux

yarn create react-app %PROJECT_NAME% --template quickstart-redux

npx command installs most recent stable version of CRA from npm. --template parameter points to this template, note that cra-template- prefix is omitted.

Then

cd %PROJECT_NAME%
yarn start

Motivation

I use Create React App pretty much often. But I hate to write same boilerplate code to make Redux working and configure some other useful stuff again and again. This template contains test and eslint configurations and Redux boilerplate code, required for rapid start of your fabulous project.

Redux

Template provides basic Redux configuration with feature based folder structure. You can use Redux devtools browser extension. Template has examples of sync (src/features/counter) and async (src/features/random) Redux features and tests for them.

Git hooks

Git hooks management is provided by husky and lint-staged.

Thus every time you commit something husky will run eslint --fix command on staged files, preventing you from committing badly formatted code. You can change or disable this behavior inside .linstagedrc config file. Before each push tests will run in the same manner.

Caveats

If pre-commit hooks not work (e. g. your code is not linted after commit), run yarn prepare in your project folder.
You need to update snapshots and fix failing tests to be able to commit or push your code.

Testing

Snapshot testing done with react-testing-library. Example tests are included. Redux connected components are tested with redux-mock-store.

Code quality tools

Code quality tools provide static check of your code and try to fix errors. Checks are triggered inside pre-commit hook. To run them manually:

yarn lint:js # runs eslint in src directory
yarn fix:js # runs eslint in src directory with --fix parameter
yarn lint:style # runs stylelint in src directory
yarn fix:style # runs stylelint in src directory with --fix parameter

eslint

Template extends CRA eslint rules with custom set, tailored for reasonable and clean development process. I added prettier to force consistent formatting and eslint-plugin-fp to avoid accidental mutations. Don't like trailing semicolons? Feel free to tweak prettier rules inside .prettierrc file to match your code style.

Eslint rules are commented for your convenience, feel free to tweak or remove them. No judgement.

// Allow jsx tags inside .js files.
"react/jsx-filename-extension": [1, {"extensions": [".js", ".jsx"]}],
// Disable props spreading (<App {...props} />) warning.
"react/jsx-props-no-spreading": 0,
// Throw warning instead of error when using array index as a key.
"react/no-array-index-key": 1,
// Allow modules with named exports only.
"import/prefer-default-export": 0,
// Force {foo: 'bar'} object literal syntax.
"object-curly-spacing": ["error", "never"],
// Throw warning instead of error when function is not properly formatted. 
// Feel free to choose your favorite option https://eslint.org/docs/rules/arrow-body-style
"arrow-body-style": ["warn", "as-needed"],
// Make prettier code formatting suggestions more verbose.
"prettier/prettier": ["warn"],
// Throw warning when <a href="#"> or <a href="javascript:void(0)"> are used.
// Use <button> instead.
"jsx-a11y/anchor-is-valid": ["warn", {"aspects": ["invalidHref"]}],
// Allow using (props) => <Component /> and ({propName}) => <Component /> syntax.
"react/destructuring-assignment": "off",
// Disable <Fragment> => <> replacement. Feel free to change
"react/jsx-fragments": "off",
// Below is the set of functional rules to warn developer about accidental mutations, 
// which may cause error in reducers etc.
// No delete operator.
"fp/no-delete": "warn",
// Warning when Object.assign(a, b) used, since it mutates first argument.
// Object.assign({}, a, b) is ok.
"fp/no-mutating-assign": "warn",
// Warning when mutating method (pop, push, reverse, shift, sort, splice, unshift, etc) 
// is used. Ramda and lodash/fp are allowed (_.pop, R.push)
"fp/no-mutating-methods": [
  "warn",
  {
    "allowedObjects": ["_", "R"]
  }
],
// Warning when mutating operators (++, --, etc) are used, object = {} also. 
// `Component.propTypes`, `Component.defaultProps`, common.js (`module.exports`)
// and `ref.current` are ok.
"fp/no-mutation": [
  "warn",
  {
    "commonjs": true,
    "allowThis": true,
    "exceptions": [{"property": "propTypes"}, {"property": "defaultProps"}, {"property": "current"}]
  }
]

stylelint

Template includes stylelint, to check CSS/SASS/LESS files. We are using stylelint-config-standard rule set extended with:

// Check `calc` functions formatting, required for `calc` to work in IE11
"function-calc-no-unspaced-operator": true,
// Custom rules (aka CSS vars) should go first
"order/order": [
  "custom-properties",
  "declarations"
],
// Require rules to be in alphabetical order
"order/properties-alphabetical-order": true,
// Disallow vendor prefixes, since CRA has autoprefixer enabled
"property-no-vendor-prefix": true,
"media-feature-name-no-vendor-prefix": true,
"at-rule-no-vendor-prefix": true,
"selector-no-vendor-prefix": true,
// Limit rules nesting for readablity purposes
"max-nesting-depth": 3,
// Limit selector complexity for readablity purposes
"selector-max-compound-selectors": 5

Stylelint errors don't prevent build of application in development mode.

Styling

Template uses vanilla CSS with autoprefixer enabled. To avoid classname collisions and reduce nesting we are using css-modules. To make css-modules work, stylesheet file name should have .module suffix.

import React from 'react';
import classes from './Component.module.css';

const Component = () => (
  <div className={classes.wrapper}>Component</div>
)

CRA doesn't support style pre-processors except SASS. But this doesn't mean, that we shouldn't use them. In order to add support for custom style processor without ejecting, we can use file watchers. File watchers will track changes in style files and compile them to vanilla CSS, consumed by CRA.

SASS/SCSS

SASS/SCSS support comes "out of the box" in CRA. To enable it:

Install node-sass
```
yarn add node-sass --dev
```

Import SASS/SCSS files straight into Component.

import React from 'react';
import classes from './Component.module.scss'; // note the changed extension

const Component = () => (
  <div className={classes.wrapper}>Component</div>
)

Change .lintstagedrc to lint scss files instead of css.

{
  "*.js": [
    "eslint --fix"
  ],
  "*.scss": [
    "stylelint --fix"
  ]
}

You can see all changes required to enable SASS/SCSS in corresponding PR.

PostCSS watcher

Install postcss-cli and related plugins:

yarn add --dev postcss-nested postcss-cli postcss-preset-env npm-run-all

Modify package scripts:

{
    "build:style": "postcss src/**/*.pcss --dir src --base src --ext css",
    "watch:style": "yarn build:style -w",
    "start": "npm-run-all -p watch:style start:js",
    "start:js": "react-scripts start",
    "build:js": "react-scripts build",
    "build": "npm-run-all build:style build:js"
}

Add postcss.config.js file in the root folder. With following configuration:

const pkg = require('./package.json');

module.exports = {
  plugins: [
    require('postcss-nested'), // handle nested selectors, like LESS or SASS
    require('postcss-preset-env')({
      browsers: pkg.browserslist.production, // use browsers list from production mode
      stage: 1,
    }),
  ],
};

Add rule to .gitignore and .stylelintrc to ignore all css files, since we are generating them.

.gitignore
```
# css
*.css
```
.stylelintrc
```
 {
 "ignoreFiles": ["**/*.snap", "**/*.css"]
 }
```

Change .lintstagedrc to lint pcss files instead of css.

{
  "*.js": [
    "eslint --fix"
  ],
  "*.pcss": [
    "stylelint --fix"
  ]
}

You can see all changes required to enable PostCSS in corresponding PR.

Less watcher

Install less and related plugins:

yarn add --dev less less-watch-compiler npm-run-all

Modify package scripts:

{
    "build:style": "yarn watch:style --run-once",
    "watch:style": "less-watch-compiler src src",
    "start": "npm-run-all -p watch:style start:js",
    "start:js": "react-scripts start",
    "build:js": "react-scripts build",
    "build": "npm-run-all build:style build:js"
}

Add rule to .gitignore and .stylelintrc to ignore all css files, since we are generating them.

.gitignore
```
# css
*.css
```
.stylelintrc
```
 {
 "ignoreFiles": ["**/*.snap", "**/*.css"]
 }
```

Change .lintstagedrc to lint less files instead of css.

{
  "*.js": [
    "eslint --fix"
  ],
  "*.less": [
    "stylelint --fix"
  ]
}

You can see all changes required to enable Less in corresponding PR.

Absolute imports

You can use source folder relative paths for imports. import Component from './../../../../../../src/components/Component' becomes import Component from 'components/Component'. Configuration is inside jsconfig.json file. You will love it 💖!

├── .env # dotenv config file
├── .eslintrc # eslint configutation
├── .lintstagedrc # lintstaged configutation
├── .nvmrc # required Node version
├── .prettierrc # prettier configutation
├── .stylelintrc # stylelint configutation
├── README.md # this file
├── README_CRA.md # original Readme from CRA
├── .gitignore
├── huskyrc-template # template for husky configuration
├── jsconfig.json # absolute path configuration
├── public # public assets
└── src
    ├── components # React components folder
    ├── config.js # shared config file
    ├── features # features logic folder
    ├── index.css
    ├── index.js # entry point file
    ├── serviceWorker.js # service worker boilerplate
    ├── setupTests.js # configuration ti run jest tests
    ├── withProvider.js # utility to generate Provider components
    └── withReduxFeatures.js # Redux store HOC

Feature architecture

Feature is a minimal working set of code capable of performing business logic task (e.g. event tracking, shopping basket etc). From the architectural point of view feature is ES Module. Exports of the module (see index.js in each folder) define feature's public interface.

Features live in the src/features folder.

Feature interface

All possible exports from the feature module can be divided in two groups:

Selectors return data from the feature state or external source.
Action creators mutate data inside feature state or perform externally applied actions (ajax requests, websocket messages etc).

Both groups are implemented as React hooks.

Rules and limitations

Each folder has index.js file which contains all public methods of this feature. Please do not import directly from feature files. They considered to be private methods.
In order to avoid circular dependencies don't use own index.js defined exports inside module, use relative imports instead.
Features may depend on other features existing using public interface.
Features' hooks may and should be used in React components. Please avoid making React components too smart in terms of business logic. Use features instead.
Some features may require internal state. State management is provided by Redux.
Though Redux state is not mandatory for the feature. Some features may only depend on external sources (ajax endpoints, URL parameters etc).

umitduran/cra-template-quickstart-redux