Learn Hapi, Puppeteer and Svelte

OpenGraph images are the images you see when you paste a link into a social platform and it "unfurls" into an image, title, and description. This happens on Twitter, Discord, Slack, and many other platforms. This collection goes over everything from designing OpenGraph images in Figma, to implementing them in CodeSandbox, to returning headless browser screenshots from Netlify Functions, and finally using Cloudinary as a write-through cache. 

You will come away from this collection with the ability to ship an API that you can use on any of your sites, and also on-demand, that can generate images for not only OpenGraph unfurls, but also for Instagram, GitHub, and more. Using headless browsers with playwright to generate our images means we get full access to all the responsive power of CSS and all the logical power of JS to handle layout, importing assets like pngs, choosing different fonts, and more.

The image below is generated via the project you'll build and deploy in this course

![An example opengraph image](https://relaxed-payne-d1bfbe.netlify.com/opengraph?title=Building%20an%20OpenGraph%20image%20generation%20API%20with%20Cloudinary%20Netlify%20Functions%20and%20React&tags=figma,netlify%20functions,playwright&author=chrisbiscardi)

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

Building an OpenGraph image generation API with Cloudinary, Netlify Functions, and React

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

End-to-end testing assures you of a few things: that all the integrated pieces of an application properly function, all those pieces work together as expected, and your tests include and simulate real-user scenarios — something unit and integration tests just don't do.

This course introduces you to two great tools for E2E testing: 

* Puppeteer opens and runs applications in a Chromium browser and performs the actions it's given.
* Jest asserts that the integrated pieces work as expected and that add-on libraries like Faker and pixelmatch take our tests to the next level.

Over 9 lessons, we will create common application features and use Puppeteer and Jest to run different types of tests against them. You'll get practice using these tools to render content, mimic user activity, automate tests, and measure the overall performance of your application.

jest

End to End Testing with Google's Puppeteer and Jest

hapi is a battle-tested, full-featured, framework for building web applications and services with Node.js. With integrated support for essentials like authentication, caching and validation, and a powerful plugin system, hapi is ideal for projects and teams of any size.

This course will introduce hapi, some of it’s plugins, and guide you through many of hapi’s core features.

A rich framework for building applications and services hapi enables developers to focus on writing reusable application logic instead of spending time building infrastructure.

hapi

Introduction to Node Servers with Hapi.js

View engines, or template engines, allow you to maintain a clean separation between your presentation layer and the rest of your application. This video will demonstrate how to use the vision plugin with hapi to enable template support.

hapi.js - View engines 

hapi does not support serving static files out of the box. Instead it relies on a module called Inert. This lesson will cover serving static files using Inert's custom handlers.

hapi.js - Serving static files

Routing is a fundamental aspect of any framework. In this lesson, you'll learn how to use path parameters in hapi's router. We'll also touch on how the router uses specificity to order routes internally.

hapi.js - Route parameters

hapi doesn't ship with logging support baked in. Luckily, hapi's rich plugin ecosystem includes everything needed to configure logging for your application. This video will introduce good, a process monitor for hapi, and good-console, a reporter for good that outputs to standard out.

hapi.js - Logging with good and good-console

hapi makes handling POST and PUT payloads easy by buffering and parsing them automatically without requiring additional modules or middleware. This video will demonstrate how to handle JSON and form based request payloads via hapi's route configuration.

hapi.js - POST and PUT request payloads

hapi's reply interface is one of it's most powerful features. It's smart enough to detect and serialize objects, buffers, promises and even streams. This video will demonstrate first hand how to use the reply method to send your data to the client, no matter the format.

hapi.js - Replying to Requests

Think of hapi's `reply()` function as "what you want to say" and the `response` object as "how you want to say it". While `reply` controls the payload sent to the client, the `response` object will allow you to control how the client interprets the payload by manipulating status code, content type, state and more.

hapi.js - Using the response object

hapi automatically responds with JSON for any error passed to a route's `reply()` method. But what if your application needs errors rendered in HTML? This lesson shows how to implement friendly HTML error messages using hapi extension events.

hapi.js - Friendly error pages with extension events

hapi supports request validation out of the box using the joi module. Request path parameters, payloads, and querystring parameters can be validated with joi's simple, yet powerful, notation. This lesson covers the basics of validating requests using joi.

hapi.js - Request Validation with Joi

hapi has built-in support for parsing cookies from a request headers, and writing cookies to a response, making state management easy and straight-forward. It even has built in support for cookie encryption and auto detects when a cookie contains JSON, parsing or stringifying automatically.

hapi.js - Managing State with Cookies

hapi is a rock solid server framework for Node.js. Its focus on modularity and configuration-over-convention makes it the perfect match for any size development team. This video will introduce you to hapi by showing you the bare minimum needed to run a hapi server.

hapi.js - Up and running

Instead of using middlware, hapi provides a number of points during the lifecycle of a request that you can hook-in to provide additional functionality, called "extension events". This lesson will give you an introduction to using extension events, and show how they can be used to manipulate the request or response in-flight.

hapi.js - Extending the request with lifecycle events

In this lesson we are going to set up our basic app, set our environment variables, define our targeted viewport, and install Jest, Puppeteer, and Faker. We'll use these features to write our end to end tests. 

Setup and Install Dependencies for Testing with Google's Puppeteer

Now that we have our setup and environment ready for using Puppeteer to test our create-react-app, we can write our first tests. We will test our h1 and navigation, to make sure that they load correctly. In this lesson, we will be able to watch puppeteer open up a browser and evaluate our tests in real time. 

Test HTML Content on a Webpage with Puppeteer

In this lesson we are going to test a form submission by replicating keyboard input, mouse clicks, and touchscreen events. This will be done with random user information generated by Faker. We will test this in different contexts, including an iPhone 6 environment.

Replicate User Activity with Faker and Puppeteer

In this lesson we are going to test that a cookie is saved to the document whenever our login form is submitted. Then we will also learn how to set cookies from within our tests. 

Work with Document Cookies in Tests with Puppeteer

In this lesson we are going to write two tests that check our application for any console logs an page errors. We will also learn how we can log these out to our terminal. 