Learn Jasmine, Mocha and Serverless

Starting from a prebuilt frontend, Jason Lengstorf guides you through the creation of a "Corgi Up-boop App" that uses Netlify Functions and Hasura. You can view [the deployed final product on Netlify](https://egghead-serverless-functions.netlify.app/).

You'll set up the Netlify CLI, and configure a local development environment before writing and deploying functions with a few different use cases.

The first example function bypasses CORS restrictions to retrieve corgi data from an example third-party API.

Next, you'll configure environmental variables to securely communicate with the Unsplash API without exposing private keys to the client.

Serverless functions don't persist data by themselves, so we will use  Hasura to create a GraphQL API for tracking the number of "boops" each corgi receives.

This course is an excellent illustration of the speed of Serverless functions, and how fast you can implement functionality in your web applications.

An all-in-one workflow that combines global deployment, continuous integration, and automatic HTTPS.

netlify

Build a Corgi Up-boop Web App with Netlify Serverless Functions and Hasura

Create a serverless application and deploy it in under thirty minutes!

We'll be using Netlify, Vite, TypeScript, and React in our project. This stack synergizes extremely well for rapidly developing professional-quality applications. 

If you haven't heard of Vite, it's the French word for quick! It's also a build tool that consists of a dev-server and an extremely fast bundler. It makes for a rapid development loop.

As for the rest. Netlify makes hosting fast and easy with serverless functions and continuous deployment. React enables you to quickly create reusable components. And TypeScript helps you write cleaner code that is easier to refactor. 

So get started and learn how to use this stack in your own applications!

Create a TypeScript powered serverless React application

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

In this lesson Trevor looks at testing AngularJS controllers with scope inheritance with Jasmine and test spies.

Testing Controllers With Dependencies

Chai is a BDD / TDD assertion library for node and the browser that can be delightfully paired with any javascript testing framework.

chai

Every dependable library needs to have tests to ensure that you don't push accidental bugs. In this lesson, see how you can set up mocha and chai to start testing your library.

Setting up Unit Testing with Mocha and Chai

Now that you've got everything set up with mocha and chai, it's time to actually write tests. In this lesson you'll learn how to use `describe` and `it` to outline your tests and make sure you don't break your library in the future.

Unit Testing with Mocha and Chai

Custom Jasmine Matchers are a great way to keep your AngularJS Unit Tests clean and tidy. We want to make expectations **readable** and express the intent of the test. Custom matchers help to accomplish this.

Custom Jasmine 1.3 Matchers

Mocha is a feature-rich JavaScript test framework running on Node.js and in the browser, making asynchronous testing simple and fun. Mocha tests run serially, allowing for flexible and accurate reporting, while mapping uncaught exceptions to the correct test cases.

mocha

Mocha is a testing framework that provides structure for unit tests. In this lesson, we will be setting up Mocha with npm and npm scripts, writing a "Hello World" unit test, then writing the code to make the test pass (as an example of Test Driven Development (TDD), with the "red-green-refactor" workflow).

JavaScript Testing Fundamentals: Hello world unit test with Mocha (in ES6)

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

An introduction on unit testing a ReactJS component using Webpack and Jasmine. Learn how to use Webpack to package and import dependencies plus take advantage of the babel-loader to write a simple Jasmine spec using the latest ES6 syntax.

Unit testing a React component using Jasmine and Webpack

In this lesson, we will use Chai's request method to test our Node application's API responses.
By the end of this lesson, you will know how to:
- install the prerequisites to use mocha and chai in your application
- test for HTTP status response codes
- test for a string of text on a page
- test for a json response and validate the properties of the object
- write tests that not only verify the response of your application, but the behavior as well


Test Node RESTful API with Mocha and Chai

AngularJS provides helpers for convenient testing of your application. In this lesson you will learn how to test a basic controller with Jasmine and Angular.

Testing a Controller

Writing great ES6 style Promises for Node.js is only half the battle. Your great modules must include tests as well to ensure future iterations don't break them. In this lesson, I show you a simple ES6 Promise in Node.js, then walk you through creating tests in Mocha using chai and chai-as-promised to test both resolve and reject methods.

Testing ES6 Promises in Node.js using Mocha and Chai

In this lesson John shows some tricks for speeding up your test suite. He digs into some handy features of WebStorm, including the *ddescriber* plugin, as well as some alternative methods for Jasmine for selectively running your tests.

Speed Testing with WebStorm and Jasmine

One of the beautiful things about dependency injection in your AngularJS apps is the ability to replace dependencies in your unit tests. In this lesson Trevor looks at how to configure Jasmine spies as injectable replacements for dependencies for testing.

Inject Jasmine Spies With $provide

Testing is a first class citizen in AngularJS. It is at its heart and soul. This lesson demonstrates using Karma to write a simple unit test for a Filter.

Unit Testing AngularJS

Unit testing a React component using Webpack and Jasmine, can involve slow and repetitive tasks when confirming that tests are passing when your code changes. For example, manually running commands instructing webpack to compile code plus refreshing the browser. This lesson demonstrates how to speed up your development time by automating these tasks using webpack-dev-server.

Reloading React component tests using webpack-dev-server

In this lesson, you will learn how to verify your API server is returning HTTP 400 responses when clients submit incorrect data. Returning HTTP 400 ensures that your clients are notified of the incorrect usage. Testing for them ensures your API returns errors instead of incorrect responses when supplied with incorrect data.

Test for HTTP 400 responses with Mocha and Chai

Using Jasmine, this lesson will look at testing an AngularJS service.

Testing a Service

Unit testing functions that invoke callbacks can require a lot of setup code. Using `sinon.spy` to create a fake callback function can simplify your unit tests while still allowing you to observe the output of the function you're testing.

Unit Test a Function that Invokes a Callback with a Sinon Spy

When testing functions that make HTTP requests, it's not preferable for those requests to actually run. Using the `nock` JavaScript library, we can mock out HTTP requests so that they don't actually happen, control the responses from those requests, and assert when requests are made.

Mock an HTTP request using Nock while unit testing

Node.js is a platform built on Chrome's JavaScript runtime for easily building fast, scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices.

node

When mocking a JavaScript function during a unit test, it can be helpful to force a mock function to return a value of your choosing. This allows you to verify that functions you're testing will behave correctly for every possible use case.

Much like [`sinon.spy()`](https://sinonjs.org/releases/v7.0.0/spies/), [`sinon.stub()`](https://sinonjs.org/releases/v7.0.0/stubs/) creates a mock function that prevents a real function from running. But, unlike `spy`, it also allows you to declare what value you'd like the mock function to return.

Mock a function's return value using a Sinon stub

Sometimes when writing a unit test, you know that the module you're testing imports a module that you would like to observe, or at the very least mock to prevent side effects like network activity or file system operations.

For JavaScript unit tests that run in Node, we can hijack the built-in `require` function by using the [`proxyquire`](https://www.npmjs.com/package/proxyquire) module, which allows us to mock one or more modules that are second-class dependencies in our unit test, replacing them with whatever we want.

This means we could replace functions with [no-ops](https://en.wikipedia.org/wiki/NOP_%28code%29) to prevent side effects, or replace them with [Sinon spies](https://egghead.io/lessons/mocha-unit-test-a-function-that-invokes-a-callback-with-a-sinon-spy) to observe the inner workings of the module you're testing.

In this video, we'll demonstrate the basics of using Proxyquire to prevent and observe a file system operation.