inianantony/course-management

Building Applications in React and Redux

Get Started

1. Install Node 8 or newer.
2. Navigate to this project's root directory on the command line.
3. Install Node Packages. - npm install
4. Install React developer tools and Redux Dev Tools in Chrome.
5. Having issues? See below.

Having Issues? Try these things first:

1. Run npm install - If you forget to do this, you'll get an error when you try to start the app later.
2. Don't run the project from a symbolic link. It will cause issues with file watches.
3. Delete any .eslintrc in your user directory and disable any ESLint plugin / custom rules within your editor since these will conflict with the ESLint rules defined in the course.
4. On Windows? Open your console as an administrator. This will assure the console has the necessary rights to perform installs.
5. Ensure you do not have NODE_ENV=production in your env variables as it will not install the devDependencies. To check run this on the command line: set NODE_ENV. If it comes back as production, you need to clear this env variable.
6. Nothing above work? Delete your node_modules folder and re-run npm install.

Production Dependencies

Dependency	Use
bootstrap	CSS Framework
immer	Helper for working with immutable data
prop-types	Declare types for props passed into React components
react	React library
react-dom	React library for DOM rendering
react-redux	Connects React components to Redux
react-router-dom	React library for routing
react-toastify	Display messages to the user
redux	Library for unidirectional data flows
redux-thunk	Async redux library
reselect	Memoize selectors for performance

Development Dependencies

Dependency	Use
@babel/core	Transpiles modern JavaScript so it runs cross-browser
@testing-library/react	Test React components
@wojtekmaj/enzyme-adapter-react-17	Configure Enzyme to work with React 17
babel-eslint	Lint modern JavaScript via ESLint
babel-loader	Add Babel support to Webpack
babel-preset-react-app	Babel preset for working in React. Used by create-react-app too.
css-loader	Read CSS files via Webpack
cssnano	Minify CSS
enzyme	Simplified JavaScript Testing utilities for React
eslint	Lints JavaScript
eslint-loader	Run ESLint via Webpack
eslint-plugin-import	Advanced linting of ES6 imports
eslint-plugin-react	Adds React-related rules to ESLint
fetch-mock	Mock fetch calls
html-webpack-plugin	Generate HTML file via webpack
http-server	Lightweight HTTP server to serve the production build locally
jest	Automated testing framework
json-server	Create mock API that simulates create, update, delete
mini-css-extract-plugin	Extract imported CSS to a separate file via Webpack
node-fetch	Make HTTP calls via fetch using Node - Used by fetch-mock
npm-run-all	Display results of multiple commands on single command line
postcss	Post-process CSS
postcss-loader	Post-process CSS via Webpack
react-test-renderer	Render React components for testing
redux-immutable-state-invariant	Warn when Redux state is mutated
redux-mock-store	Mock Redux store for testing
rimraf	Delete files and folders
style-loader	Insert imported CSS into app via Webpack
webpack	Bundler with plugin ecosystem and integrated dev server
webpack-bundle-analyzer	Generate report of what's in the app's production bundle
webpack-cli	Run Webpack via the command line
webpack-dev-server	Serve app via Webpack

Points

1. Add index file to mound our app inside src folder
2. Add entry point for the app with index.js inside src folder
   • Import React, render from react and react-dom
   • render a simple <Hi/> component
3. Use webpack to deliver our app
   • webpack has a local webserver that delivers our app
   • Its common to have webpack config for dev and prod in the root folder
   • since we are using node, we will use the commonJS syntax like require & module.exports in the webpack config
   • we configure the NODE_ENV as development
   • In development the bundelled files are delivered from memory
4. Configuring Babel & ESLint
   • To trnaspile moden js & jasx to any browser with ES5 standard
   • Can be configured through package.json under the section babel or through its own config file
   • Use the preset for react so that it configures babel for all the required settings
   • ESLint is also configured from package.json under the section eslintConfig
   • Set up webpack to file watch for us and lint any errors by changing the module loaders and add eslint-loader
5. Four ways of creating react components
   • createClass React.createClass({ render: function(){ return (<p>Hi</p>); } } );
   • ES class class Hello extends React.Component { render() { return (<p>Hi</p>); } }
   • Function Component function Hello(props) { return (<p>Hi</p>); }
   • Arrow function const Hello = (props) => <p>Hi</p>
   • Prefer Functional components
   • Container components are concerned with behaviour and littl/no markup. These are responsible for passing the data / actions to child components and they hold the state.
   • Presentation components contain all the markup and they receive the data from the container components through props and are not stateful
6. Folder structure
   • src/components
   • each module of the application is in a seperate folder as src/components/login
   • Add about and home modules
7. Redux
   • Immutable store, Action trigger, Reducer
   • store is created in App's entry point by using createStore(reducer);
   • Reducers are pure functions, no mutations or sideeffects, no randon, no datetime, no api calls etc
   • React-Redux has Provider component which attaches the entire app to the redux store. Connect is a function which connects components to the redux store for specific states
   • Provider component is used to wrap app's top level component to the store
   • Connect function wraps the component so that its connected to the store
   • Connect function has two optional parameters mapStateToProps and mapDispatchToProps. mapStateToProps is used to map a set of values from the state and to alter the shape of the state as needed for the component. mapDispatchToProps is used to map which actions are exposed to dispatch so that it can update the state. The mapDispatchToProps can be ingored to the connect function and in this case the dispatch menthod is available to the component and the component need to use, this.props.discpatch(loadUsers());. We can also manually wrap the mapdispatchTo Props

    function mapDispatchToProps(dispatch){
        return {
            loadUsers: ()=> dispatch(loadUsers());
        };
    }

   • The next option is to use bindActionCreators

   function mapDispatchToProps(dispatch) {
     return {
       actions: bindActionCreators(actions, dispatch),
     };
   }

   • The last choice is to use the return object

   const mapDispatchToProps = {
     loadUsers,
   };

8. Redux middleware ( we are using redux-thunk , the other popular one is redux-saga)
   • Redux middleware runs betwen the action and the action reaching the reducer.
   • In redux actions are synchronous and they must return an object and so to handle async calls we use a middleware
   • Normally we return an action from the ActionCreators, with redux-thunk we return a function
   • Thunk takes in the stores dispatch and getState parameters and they are passed automatically by the middleware
   • redux-think is configured when we create the store and is used in the applyMiddleware function call
9. Others
   • We use webpack webpack.DefinePlugin to publish the api url into the environment variable