Learn Cypress, Immutable and Rxjs

When a manager gives us the requirements for an application feature, they don't care too much about *how* we build it. And often times, they think that hard things will be easy.

Dealing with time and coordinating different types of events can be tricky.

Luckily, we have RxJS to help!

In this course, you will use RxJS to build a loading spinner in an app that meets the ever-changing requirements from a mock Product Manager.

You'll also learn how to implement a "Konami Code" style feature that listens for a correct sequence of keys to be typed in a set amount of time.

Follow the thought process that Rares uses as he breaks problems down into manageable pieces that remain flexible, and become more comfortable solving problems reactively.

RxJS is a library for composing asynchronous and event-based programs by using observable sequences. 


rxjs

Thinking Reactively with RxJS

Imagine the following.

You join a new project and after getting access to the repo you notice that there's no tests.

You decide to ask the team whether they are in different repo or something and unfortunately the answer is:

>We don't have any tests, we didn't have the time.

😐

In this collection we're going to learn how to add e2e tests with cypress.io to an existing React app in order to do two things:

- 🌟 Ensure that our app currently works as intended
- 🌟 Allow us to add features to it with a technique called "Cypress Driven Development" 

In less than 20 minutes we're going to go through:

- ⚡️Adding cypress.io setup to an existing project
- ⚡️Testing search functionality with `data-cy` properties
- ⚡️Using "Cypress Driven Development" to add a new feature to an app
- ⚡️Use Cypress UI to debug an API response
- ⚡️How to use `cy.only` and `cy.skip` in order for us to build our e2e test suite faster

and much more!

Fast, easy and reliable testing for anything that runs in a browser.

cypress

Add e2e tests with cypress to a React application

One of the most important — but most ignored — practices for web developers is performing end-to-end testing on applications before they go live into production. You know: making sure they work like they’re supposed to. But testing can be tedious, and definitely not fun.

In this course, Brett Cassette will show you how you can test all layers of your application stack, simultaneously, with Cypress. When you use Cypress, it’s like having a robot that uses your app the way a real user would. Cypress reports if things work the way you designed them to — and if they don’t — every step of the way. And it’s fun.

After completing this course, you’ll be ready to apply the same E2E testing principles to your own applications. Stop leaning on your QA department (if it exists) to stress-test your application, and ship your app knowing it’s ready. 


Test Production Ready Apps with Cypress

_Feels like magic._

It’s a beautiful feeling when technology works in mysterious, miraculous ways. So smooth! So effortless! So…

_Wait, that’s not right. What’s it doing? I don’t get it. Help!_

…until you encounter unexpected behavior. Good luck debugging magic.

To use technology to its fullest, you need to understand how it’s accomplishing the tasks set before it. 

This course de-mystifies RxJS. It feels like magic, but it’s also one of the most laborious technologies to learn in front-end web development. We’ll open up the internals to take an up-close look at how RxJS handles Async programming so smoothly.

Over 12 lessons and 31 minutes, you'll get a handle on:

- how RxJS pushes values from observables to subscribers, which take care of the output. 
- how operators handle all of the "in-between" operations where you can manipulate the values while they're still in-flight.
- the internals of operators and subscribers and how to customize operators to your specific needs.


Build Your Own RxJS Pipeable Operators

The tools available for unit testing have come a long way. While testing may never be “easy”, the available tools have certainly moved testing closer to the simple end of the spectrum. Full end to end testing hasn’t quite kept the same pace and as a result many applications are testing manually and often by users in production. Cypress provides a testing environment that makes end-to-end testing fast and reliable with a simple API that makes creating automated unit tests for your web applications a no-brainer.


End to End testing with Cypress

***Note: RxJS imports have changed since the publication of this course, these changes to RxJS have been reflected in the code examples underneath each lesson. The concepts being taught on RxJS are still applicable.***

Vue.js is an amazing framework that can easily update and reflect user input using templates and data-binding. But there are many scenarios where complex asynchronous behaviors (like loading data, handling "pending" states, timeouts, etc) are solved much easier by leveraging the streaming capabilities of RxJS. This course covers how to setup and use the features of "vue-rx" to enable streams within your templates and easily solve complex scenarios.

Vue (pronounced /vjuː/, like view) is a progressive framework for building user interfaces. Unlike other monolithic frameworks, Vue is designed from the ground up to be incrementally adoptable. The core library is focused on the view layer only, and is very easy to pick up and integrate with other libraries or existing projects. On the other hand, Vue is also perfectly capable of powering sophisticated Single-Page Applications when used in combination with modern tooling and supporting libraries.

Build Async Vue.js Apps with RxJS

***Note: Active maintenance for Recompose has been discontinued since the announcement for React hooks. Your existing code using Recompose will still work. Recompose is not compatible with RxJS version 6 and beyond. You can read more about the decision [here.](https://github.com/acdlite/recompose/issues/756#issuecomment-438674573)*** 


Loading data and handling events almost always introduces layers of complexity into React apps. Recompose and RxJS solve your async problems by using Streams to output components. This course walks you through combining the powers of React and RxJS to stream data into JSX with streaming patterns and pure React components.

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

Build React Components from Streams with RxJS and Recompose

Introductions to various RxJS Operators including of, from, fromEvent, interval and zip.

RxJS Operators

***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

***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 learn to identify common mistakes with RxJS that usually make code harder to read and even introduce bugs. Most of these mistakes are related to Subject, subscribe, and subscriptions. We are going to see how to use only Observables and convenient operators made for solving those mistakes, such as fromEvent, takeUntil and switchMap. By the end of this course, you will have a more immediate intuition on what patterns are simple and safe in RxJS.

Save time avoiding common mistakes using RxJS

If you have used RxJS Observables, it is likely you have seen the flatMap or switchMap operators. They are very powerful operators that can be used in various situations, while being common for dealing with HTTP requests. These operators may look mysterious at first, but turn out to be simple flattening operations on higher order Observables. 

In this course you will learn what is a higher order Observable, when does it occur in real applications, and how to handle them with operators like switchMap. Throughout this course we will see real applications of these operations.

Start following this course if you have some understanding of RxJS, but want to gain advanced skills in the art of using operators.

If you're new to RxJS, we highly recommend the [Introduction to Reactive Programming using RxJS](https://egghead.io/courses/introduction-to-reactive-programming) to begin with, and then [RxJS Beyond the Basics: Operators in Depth](https://egghead.io/courses/rxjs-beyond-the-basics-operators-in-depth) to understand operators.

If you're an absolute beginner to the concept of Observable and async streams, we highly recommend starting with [Jafar Husain's excellent introduction](https://egghead.io/courses/mastering-asynchronous-programming-the-end-of-the-loop).

Use Higher Order Observables in RxJS Effectively

***Note: RxJS imports have changed since the publication of this course. The concepts being taught on RxJS are still applicable.*** 

RxJS Subjects are a source of confusion for many people using RxJS. For many, the Subject is the obvious and only answer to every problem. Subjects are incredibly useful and necessary, but the key is to know when to use them for solving specific problems that you encounter.

In this course, we are going deep into RxJS Subjects and multicasting operators. You'll gain a solid understanding of when, where, and how to use these powerful tools.

If you are new to RxJS, or want a refresher please check out this course **[Introduction to Reactive Programming](https://egghead.io/courses/introduction-to-reactive-programming)**.

RxJS Subjects and Multicasting Operators

In this course, you will learn more about using observables in Angular. We are going to how we can leverage the power of observables and RxJS to build a rock solid instant search component with a handful of operators.

You will learn operators by applying them to a real-world component. By the end of this course, you will have a clear understanding of how components can be designed around the concept of event streams which are wired together like modular building blocks.

All of this in about 11 minutes! 😄

This course assumes a solid understanding of fundamentals.
We have Intermediary Angular courses that'll get you up to speed.  
- [Dependency Injection](https://egghead.io/courses/angular-dependency-injection-di-explained)
- [Components, Directives](https://egghead.io/courses/building-angular-components)
- [Forms](https://egghead.io/courses/learn-the-basics-of-angular-forms)
- [Router](https://egghead.io/courses/intro-to-angular-router) 
- [Animating Web Apps](https://egghead.io/courses/animate-angular-web-applications)

⚠ The code used in the course is of Angular `^2.0.0`, and the code given in the [transcript](https://codesandbox.io/s/54xv161qq4?from-embed) is of Angular `7.0.3`. **An updated version of the code can be found [here](https://github.com/eggheadio-projects/build-an-angular-instant-search-component-course-notes)** *(updated 5/8/2020)*. The code for each lesson resides in the respective branch on the repository.

Angular is a development platform for creating applications using modern web standards. Angular includes a wealth of essential features such as mobile gestures, animations, filtering, routing, data binding, security, internationalization, and beautiful UI components. It's extremely modular, lightweight, and easy to learn.

angular

Build an Angular Instant Search Component

Operators are the core building blocks for reacting to data in your JavaScript applications.

In this course you will learn what operators are, and then take a tour of the most useful operators that RxJS has to offer.

RxJS Beyond the Basics: Operators in Depth

There are plenty of introductions to RxJS, but few resources that take you deep into the library, providing an accurate understand of what each piece performs.

In this course we will gain intermediate knowledge of RxJS, focusing on one aspect: how to create Observables. We will see how Observables compare to functions, how they compare to ES6 generators, what are the empty(), throw() and never() Observables, and other static factories that help in making Observable sequences.

Start following this course if you have a superficial understanding of RxJS, but want to gain confidence in using it.

If you're new to RxJS, we highly recommend this [Async JS course from Jafar Husain](https://egghead.io/series/mastering-asynchronous-programming-the-end-of-the-loop) to get a solid intro to the concepts. From there, you can watch this [Introduction to Reactive Programming using RxJS](https://egghead.io/series/introduction-to-reactive-programming), and you will be prepared for this course!

RxJS Beyond the Basics: Creating Observables from scratch

***⚠️⚠️⚠️ This course uses an old version of RxJS and loads data using the jQuery library which is no longer fashionable. If you can look past that and understand that the principles André is demonstrating are timeless and useful, this course is a true gem. Otherwise, this is probably not for you! ⚠️⚠️⚠️***

*Reactive*

You've probably been hearing this word recently, and it's referring to the *Reactive Programming* paradigm. One of the biggest challenges people face when learning Reactive Programming is changing their way of thinking, and in this course, you are going to exercise your mind and learn to let go of that imperative and stateful mindset.

You will also learn how can practically apply these Reactive concepts using the RxJS library! 

If you are **brand new** to reactive programming, the course [Asynchronous Programming: The End of The Loop](https://egghead.io/series/mastering-asynchronous-programming-the-end-of-the-loop), will get you up to speed. 📚

Introduction to Reactive Programming Using RxJS 5

RxJS is tremendously helpful in working with asynchronous code, but you’ve probably been stuck trying to use concepts you already know from Promises or Callbacks and applying them directly to RxJS. These lessons walk you through the step-by-step of building a simple game application with many asynchronous pieces. Each lesson focuses on a single operator or idea of how RxJS helps simplify your code as well as making you code flexible enough to easily add more asynchronous pieces as your codebase grows.

Step-by-Step Async JavaScript with RxJS

***Note: RxJS imports have changed since the publication of this course. The concepts being taught on RxJS are still applicable.**

Angular has many built-in features for working closely with RxJS to help you build entirely reactive applications. This course will teach you how to use Angular with RxJS. We will learn how to use the ngrx/store library to manage state in a clean, reactive "Redux style."

This course assumes you've got a working knowledge of Angular and reactive programming with RxJS. If you don't, you might want to watch the following courses to get you up to speed! 
- [Get Started with Angular](https://egghead.io/courses/get-started-with-angular) 
- [Introduction to Reactive Programming with RxJS](
https://egghead.io/series/introduction-to-reactive-programming). 
- [Step by Step Async Programming with RxJS](https://egghead.io/series/step-by-step-async-javascript-with-rxjs) 
- [Getting Started With Redux](https://egghead.io/series/getting-started-with-redux), a course by Redux's, Dan Abramov.

We also have Intermediary Angular courses if you'd like to acquire more in-depth knowledge. 
- [Dependency Injection](https://egghead.io/courses/angular-2-dependency-injection-di-explained
- [Components, Directives](https://egghead.io/courses/building-angular-components)
- [Forms](https://egghead.io/courses/intro-to-angular-forms)
- [Router](https://egghead.io/courses/intro-to-angular-router)
- [Animating Web Apps](https://egghead.io/courses/animate-angular-web-applications)



Build Redux Style Applications with Angular, RxJS, and ngrx/store

Your app can react in various way on different network conditions. Cypress has a great toolset for setting up those conditions, which enable you to test your app thoroughly. That way you can ship your app with confidence.

Cypress’ .intercept() command is one of the most fun command to use. And it’s also one of the most useful.

Especially when you are done with all your happy paths and want to increase your test coverage with some edge cases.

These edge cases can mean different data, headers or server behavior. You can modify all of these, dynamically or with a static fixture prepared beforehand

Test Network Edge Cases with cy.intercept() Command in Cypress

im·mu·ta·ble i(m)ˈmyo͞odəb(ə)l/ adjective - **unchanging over time or unable to be changed**.

Mutating data is the source of never ending headaches in software systems, and JavaScript code is no exception. Immutable data structures, pure functions, uni-directional data flow... you've probably been hearing these terms.

Immutable.js provides us the data structures and utilities that we need to start introducing this powerful concept of immutability into our applications.

Immutable.js provides many Persistent Immutable data structures including: List, Stack, Map, OrderedMap, Set, OrderedSet and Record.

immutable

Learn how to use Immutable.js

Web accessibility (also referred to as a11y) is the design and creation of websites that can be used by everyone. Accessibility support is necessary to allow assistive technology to interpret web pages.

React fully supports building accessible websites, often by using standard HTML techniques.

Erin Doyle is an expert in creating accessible React applications and has developed a course that will give you a concrete process for auditing react apps for accessibility. In this course, you will go through different tools and libraries to audit components in a React app.