Learn D3, Redux and Svelte

JavaScript community has been shaken recently by a release of Svelte 3 and for a good reason - it's a completely different approach than React or Vue. To quote the docs:

"[Svelte](https://svelte.dev/) is a radical new approach to building user interfaces. Whereas traditional frameworks like React and Vue do the bulk of their work in the browser, Svelte shifts that work into a compile step that happens when you build your app."

**The best part?** If you have 26 spare minutes you can learn the basics of Svelte 3 and start building your own apps with it!

Enjoy!



The magical disappearing UI framework

 - The web's JavaScript bloat crisis, solved. Svelte turns your templates into tiny, framework-less vanilla JavaScript.
 - Simple and familiar. Build apps out of composable, easy-to-write blocks using languages you already know.
 - Super fast, rock solid. Compile-time static analysis ensures the browser does no more work than it needs to.

svelte

Up and running with Svelte 3

At a high level Redux is just a dispatching system, sitting atop a finite state machine, driving our application state. It just so happens that the State ADT is good at modeling a finite state machine. It allows us to represent our stateful transactions in discrete, easily composed transactions. We can create complicated stateful transitions by composing many simple transitions into one state transaction. By using the State ADT, we should be able to model all of our application state transitions and provide a single reducer function to Redux that integrates with our state machine model.

We’ll put this theory to the test by building a Memory type game called “Anger The Bunny”.  We start of by defining our state transitions using the State ADT, starting with simple, discrete transactions and using them to create the complex transitions typical of any game. Then once we have a majority of our game logic implemented, we will integrate those with Redux.

Redux is a predictable state container for JavaScript apps.
It helps you write applications that behave consistently, run in different environments (client, server, and native), and are easy to test.

redux

Redux and the State ADT

Redux is a powerful way to manage application state, but that power can come with a lot of code. A single update can sometimes require changes across many files and the code required to define action creators and to handle those actions in your reducer can start to get pretty repetitive.

The redux-actions library offers a small but powerful API to help cut down on some of the boilerplate that is typical of an application that uses Redux to handle state management.

Reduce Redux Boilerplate with Redux-Actions

Working with forms can be laborious, but redux-form takes out the tedium and replaces it with an enjoyable way to create beautifully crafted forms. You get the benefit of integrating form state with an existing Redux application, plus the ability to track the state of your form with precision in Redux DevTools, without writing lots of boilerplate code.

In this course, we will use the redux-form package to create a form whose state is easy and enjoyable to manage. Over 46 minutes and 14 lessons, we will:
* find out how redux-form ties into a React/Redux application
* learn how to use both synchronous and asynchronous validation
* use real-world examples and effective ways of presenting relevant information to the user

Learn to create precise, reusable form components, and enjoy yourself in the process.

React is one of the web’s most popular frameworks for building JavaScript applications. 

If you know what you’re doing, React can drastically simplify how you build, use, and maintain code.

Whether you’re a React newbie or you’re ready for advanced techniques, you can level-up with egghead. Explore our in-depth courses, lessons, and community resources to build more powerful applications and crack open your career.

react

Manage React Form State with redux-form

***Note: RxJS imports have changed since the publication of this course. Operators now must be passed into `.pipe` to be applied to an observable.***

In this course we will begin with nothing more than an empty directory & a text editor. Through small, focussed lessons we’ll learn how to setup a React project that uses Redux for state management and redux-observable for asynchronous actions. We’ll see how ‘epics’ are registered and how they each receive a ‘stream’ of actions from the store. 

With an understanding of how things work, we’ll move onto solving common problems such as Ajax cancellation, creating sequences of async actions, enabling code reuse through higher-order Observables and much more. 

## **UPDATE:** 
This course is outdated, view updated material here: [Asynchronous State Management with redux-observable v1](https://egghead.io/courses/asynchronous-state-management-with-redux-observable-v1)

Up and Running with redux-observable

Managing state in modern web applications is hard. As applications grows in complexity, keeping track of state changes and mapping those changes back to your UI becomes increasingly difficult.

One way data flow makes managing state more approachable and lightens the cognitive load required to follow the flow of data through your application. Using Redux takes this idea to the next level and moves the state and the state changes and centralizes them in a global store, managed with pure reducer functions.

In this course you will learn how to build a production quality React application using Redux. We will build up from using redux by itself, so we can understand the core API and how that interacts with a React application, then we’ll move on to introduce `react-redux` to abstract away some of the underlying details and clean up our code. We’ll use middleware and a mocked API server to understand how asynchronous code fits into the Redux model and we’ll even deploy our finished work so we can see it running live in the cloud. 

If you are brand new to React, you’ll want to read the documentation and watch our free [React Fundamentals](https://egghead.io/courses/start-using-react-to-build-web-applications) course and our [Build Your First Production Quality React App](https://egghead.io/courses/build-your-first-production-quality-react-app) course. To get up to speed on Redux, you should check out Dan Abramov’s [Getting Started With Redux](https://egghead.io/courses/getting-started-with-redux) course.

Build A React App With Redux

D3, or Data Driven Documents, is the defacto standard for data visualization on the web. It's an incredibly powerful library that gives you all the tools you need to build just about visualization you can dream of.

D3 is not a collection of predefined charts. Instead, it's a robust set of utilities you can use to ingest and transform data, to map that data to screen values, and ultimately to manipulate the DOM to render your visuals.

When working with React, D3's desire to manipulate the DOM is at odds with React's goal of rendering the UI as a function of state. So how do we handle this? Simply put, we use D3 for everything up to the point where we want to render our output, and then we hand all that data to React for rendering.

In this course, we'll start from scratch and build out an SVG bar chart for some sample data. We'll lean on D3 for its tools and then hand that data off to React for rendering.

Create A Bar Chart with React and D3

Best practices for building & testing redux applications have changed dramatically over time. This course aims to be a comprehensive and up-to-date resource for those seeking to confidently test their redux apps. Whether you're just getting started or want to improve on your existing testing strategy, there will be something in this course for you.

This first few lessons of this course look at how to add jest to an existing react/redux application that was built on top of [vite](https://vitejs.dev/). We cover basic functionality like using `npm test` vs `npx jest` and generating and using [code coverage](https://jestjs.io/docs/cli#--coverageboolean) to inform our testing strategy.

The next 10 or so lessons cover the specifics of unit testing the redux code in our application. We'll go over how to test reducers, selectors and thunks. As part of this we'll touch on mocking APIs and using [Redux Mock Store](https://github.com/reduxjs/redux-mock-store) as well as running actions through our applications' actual reducers to broaden our test coverage.

In the final part of this course we'll look at how we can test our redux connected react components using the various utilities that come with the [React Testing Library](https://testing-library.com/docs/react-testing-library/intro/). We'll cover simulating various kinds of user input with the [User Event Module](https://testing-library.com/docs/ecosystem-user-event), populating our redux store with test data, using [jest spies](https://jestjs.io/docs/jest-object#jestspyonobject-methodname), how to wait for asynchronous tasks to complete, and several approaches for finding & asserting that visual elements exist on the page.

This course is built on top of content that was created for the [Modern Redux with RTK and TypeScript](https://app.egghead.io/playlists/modern-redux-with-redux-toolkit-rtk-and-typescript-64f243c8) course and I highly recommend you start there if you haven't completed it already. It does expect a *basic* familiarity with react, redux and jest. TypeScript is used in these lessons, but is not a major focus and hopefully won't distract you too much if you prefer plain JavaScript.

No matter your experience level with redux and testing react applications, I'm confident your abilities will level up as you watch this course and follow along with the examples.

Thank you!

jest

Confidently Testing Redux Applications with Jest & TypeScript

In this course we will learn and demonstrate the fundamental concepts and APIs of D3, on our way to building several common chart types. We’ll start with the building blocks upon which all D3 visualizations are built; things like scales, interpolators, and selections. We’ll see how to load data with D3, and how to put its full name, Data Driven Documents, into action. We’ll build column and bar charts, scatter plots, and area charts. Most importantly, we’ll gain an understanding of the conventions and patterns that underlie all D3 projects and examples, enabling you to dissect, understand, and build virtually any D3 visualization on the internet.

D3.js is a JavaScript library for manipulating documents based on data. D3 helps you bring data to life using HTML, SVG and CSS. D3’s emphasis on web standards gives you the full capabilities of modern browsers without tying yourself to a proprietary framework, combining powerful visualization components and a data-driven approach to DOM manipulation.

Build Interactive JavaScript Charts with D3 v4

One of the hardest things about writing non-trivial applications is managing state. In our attempt to effectively manage state, we introduce additional complexity by trying to control application flow and the amount of code volume that comes from all of this. Redux gives us the ability to address state management and communication in astonishingly simple semantics that can be explained in just a couple minutes. The beauty of Redux is that it is not only a library but a pattern that works very will within Angular 1.x applications. In this series, we are going to learn how to integrate redux (the pattern) into Eggly from scratch and then introduce **ng-redux** and add in **Redux DevTools** at the end for fun.

AngularJS is an open-source JavaScript framework, maintained by Google, that assists with running single-page applications. Its goal is to augment web-based applications with model–view–controller (MVC) capability, in an effort to make both development and testing easier.

angularjs

Build Angular 1.x Apps with Redux

In this course we take a basic shopping cart application built with React and fully power it with Redux and RTK using TypeScript. For those of you familiar with Redux Hooks, we use those here, but the emphasis is more on how the Redux Toolkit simplifies the process of setting up your redux application including building slices, reducers, selectors and thunks. Everything we do in the course is typed with TypeScript to make your application development process as smooth and powerful as possible. 

Modern Redux with Redux Toolkit (RTK) and TypeScript

This course will pick up where we left off with the [Redux Fundamentals course](https://egghead.io/series/getting-started-with-redux). If you haven't watched that yet, you are highly encouraged to do so!

You are about to learn practical production ready techniques for building your React and Redux applications. You will explore advanced state management, middleware, React Router integration, and other common problems you are likely to encounter while building applications for your clients and customers.

Even if you have already spent time studying Redux, this course will show you better practices straight from the library's creator Dan Abramov.

**[Click here to see the Community Notes on this course](https://github.com/tayiorbeii/egghead.io_idiomatic_redux_course_notes)**


Building React Applications with Idiomatic Redux

Many engineers working with redux have felt burdened by large amounts of boilerplate code and confusing indirection. These apps often rely on legacy patterns that are no longer recommended, but are still commonly found in production code bases. If you are are an engineer working on such an application, this course is for you. In it I will show you how to modernize your application, with react hooks, one component at a time. At the end of it, we'll still be using redux, but the structure and content of your code will be significantly improved.

We will cover migrating class components to functional components with [react hooks](https://reactjs.org/docs/hooks-reference.html) and how to replace `connect()` with [redux hooks](https://react-redux.js.org/api/hooks). This course will serve as a good tutorial for learning react hooks. It will also help you apply  modern patterns for using redux. These patterns, powered by the new [useSelector](https://react-redux.js.org/api/hooks#useselector) and [useDispatch](https://react-redux.js.org/api/hooks#usedispatch) hooks will transform your redux applications for the better. 

Modernizing a Legacy Redux Application with React Hooks

Redux was [announced back in 2015](https://www.youtube.com/watch?v=xsSnOQynTHs) and immediately took off as the de-facto state management solution for React. As it gained widespread traction, it also became clear that in many cases it was brought into applications prematurely. The community in some ways started to push back on its use and recommended the built-in `setState` method as an alternative. Several other state libraries also started popping up around this time. Finally, as React Hooks were announced with a built-in `useReducer` method it appeared that Redux's time was up. However, these claims have proven to be premature. Redux is not dead and instead remains React's most popular state management library`*`. 

Recent updates to redux exposing a [hooks-based API](https://react-redux.js.org/api/hooks) address some of its most serious drawbacks and make it even more appealing. This course will show you how to apply redux to a modern react hooks application. I hope you leave this course with a continued appreciation for React Hooks and renewed enthusiasm for Redux.

Thanks for watching 📺.

---

**Notes**

- This content has been inspired by the incredible work done by [Mark Erikson](https://twitter.com/acemarke) on modernizing redux and the fantastic [Redux Style Guide](https://redux.js.org/style-guide/style-guide).

- `*` Comparing [redux](https://www.npmjs.com/package/redux) with [mobx](https://www.npmjs.com/package/mobx),  [xstate](https://www.npmjs.com/package/xstate) and [flux](https://www.npmjs.com/package/flux)

Apply Redux to a Modern React Hooks Application

This course covers D3 v3. If you'd like to learn about v4 of D3 (the latest version) [click here for the course on that](https://egghead.io/courses/build-interactive-javascript-charts-with-d3-v4).

This series will gently guide you through the first steps in getting to know D3. The curve can be steep, but with a few simple tools, you'll be charting your buns off in no time flat.

Use D3 (v3) to Build Interactive Charts with JavaScript

In this comprehensive tutorial, Dan Abramov - the creator of Redux - will teach you how to manage state in your [React](/q/react) application with [Redux](/q/redux). 

[State management](https://egghead.io/playlists/react-state-management-in-2021-6732) is absolutely critical in providing users with a well-crafted experience with minimal bugs. 

It's also one of the hardest aspects of a modern front-end application to get right.

Redux provides a solid, stable, and mature solution to managing state in your React application. Through a handful of small, useful patterns, Redux can transform your application from a total mess of confusing and scattered state, into a delightfully organized, easy to understand modern [JavaScript](/q/javascript) powerhouse.

The principles of Redux aren't new, but they are packaged and presented for you in an easy to use a library that not only elevates your applications but also improves your general understanding of building JavaScript UIs.

In this course, Dan Abramov will show you the fundamentals of Redux, so that you can start using it to simplify your applications. 

There are some amazing [community notes on this course here on Github](https://github.com/tayiorbeii/egghead.io_redux_course_notes).



Fundamentals of Redux Course from Dan Abramov

We’ll refactor our existing code and break the pieces of the application into their own stateless functional components. We’ll use these components to build up our UI. We’ll also see how we can use ES6 destructuring syntax to accept just the keys we need from props to keep our JSX clean.

Refactor JSX in React to Stateless Functional Components

We’ll define a simple state object in the entry point of our application. Once the state has been defined, we’ll pass it into our root component as props and replace the static elements in our rendered output with values from the component’s props. We’ll move from static items to an array, seeing how we can use functions like map to render our UI.

Render in React Based on a Global State Object

We will learn how to use normalizr to convert all API responses to a normalized format so that we can simplify the reducers.

Redux: Normalizing API Responses with normalizr

Most of D3’s native selection APIs also return the selection (or a new selection), to enable multiple method calls to be chained together. Since the code you write isn’t on the selection prototype, chaining your methods would take some extra work. `selection.call()` will call any function reference you give it, providing the selection as the first parameter, and then it returns the selection for you to ensure chaining is supported.

Better Code Organization with selection.call() with D3 v4

We will learn how to fire up an async request when the route changes.