Learn Gulp, 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

In this series we will take a look at Gulp. Gulp is a task runner. It is the commander of our army of helper robots that take critical, yet totally mundane, tasks and perform them hundreds of times per day so we don't have to. When we sit down to work, we want to enter a single command, and then spend the rest of our day writing code, testing, and basically not thinking about how it is all glued together in the background.

Automation is critical to any project of significant size. We will start with the Eggly Bookmarks application, and develop proper build automation that will include **production ready** tools that you can start using in your applications today!

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

Angular Automation with Gulp

Creating forms is one of the simplest and most complicated things at the same time. A basic form consists of many different things happening, we have to retain the value, we have to keep watch of validation and we have to show error messages when something is invalid, this is on both the fields and on the entire form itself if we send a request off to the backend service.

So we're going to create a form using just the normal svelte features. Then we'll look into creating a form using the svelte forms lib. 

Create forms in Svelte with Svelte Forms Lib

In this lesson, we are going to learn how to create a config file to store common values so that we can reuse them multiple times in our `gulpfile.js`. As our `gulpfile.js` grows in complexity, we may find that we are introducing complex and multiple file path references. By creating a `gulp.config.js` file, we can simplify these references and make it easier to refactor and extend in the future. 

Angular Automation: Gulp Config

In this lesson, we are going to learn how to use `gulp.watch` to detect local file changes and execute additional Gulp tasks. To illustrate this concept, we are also going to hook up `gulp-jshint` to automation lint our JavaScript as we make changes to our code.

Angular Automation: Gulp Watch

Angular projects require automation. Period. 

In this series we will take a look at Gulp. Gulp is a task runner. It is the commander of our army of helper robots that take critical, yet totally mundane, tasks and perform them hundreds of times per day so we don't have to. When we sit down to work, we want to enter a single command, and then spend the rest of our day writing code, testing, and basically not thinking about how it is all glued together in the background.

Automation is critical to any project of significant size. We will start with the Eggly Bookmarks application, and develop proper build automation that will include **production ready** tools that you can start using in your applications today!

Angular Automation: Introduction to Gulp

In this lesson, we are going to learn how to copy assets from one place to another using Gulp. This is important as you start to prepare your source files to be deployed into production. We will learn how to implement `gulp.src`, `gulp.pipe` and `gulp.dest` as well as the **del** plugin as we copy our files from the source directory into a build directory.

Angular Automation: Copy Assets with Gulp

In this lesson, we are going to learn how to use the `gulp-inject` plugin to sanely and efficiently manage our file references with our HTML. Manually declaring JavaScript references will quickly get out of hand as your application grows in size and complexity. The `gulp-inject` plugin solves this problem by taking a stream of files, converting them into string references and then injecting those references into your HTML via annotations. 

Angular Automation: Gulp Inject

In this lesson, we are going to learn how to automatically serve our project via an HTTP server using `gulp-serve`. Being able to serve our project from an HTTP server allows us to bypass a myriad of development issues such as loading remote source files.

Angular Automation: Gulp Serve

In this lesson, we will learn how tasks work in Gulp. We will talk about how to define a task and what each parameter in the definition does. We will see how task dependencies work and talk about how to handle asynchronous issues using `run-sequence`.

Angular Automation: Gulp Tasks

In this lesson, we learn how to get up and running with Gulp by initializing our project with ```npm init``` and then installing the Gulp CLI globally and then installing it locally to our project. We finish the lesson off by creating our first Gulp file and running our first Gulp task.

Angular Automation: Installing Gulp Globally and Locally

Gulp is a toolkit for automating painful or time-consuming tasks in your development workflow, so you can stop messing around and build something.

gulp

Building upon the `watch` task that we begin this lesson with, we’ll look at how to create a local development server using the `app` directory as the web root. By using Browsersync to achieve this, we can also instruct all connected browsers to automatically reload each time our bundle is re-generated. Browsersync has a public `.stream()` method that is designed exactly for this purpose.

Gulp and Browserify - Adding Live Reload with Browsersync

Babel has support for the latest version of JavaScript through syntax transformers. These plugins allow you to use new syntax, right now without waiting for browser support.

babel

What is already a nice workflow using Gulp, Browserify, Watchify & Browsersync to enable auto rebuilds & live browser reloading can be further improved by adding Babelify. A simple wrapper around the popular transpiler Babel, Babelify can ‘transform’ source files as they pass through our stream to enable certain Javascript features not yet available in the Browser or Node. We end the lesson by looking at how to generate & extract sourcemaps using `exorcist`.

Gulp and Browserify - Adding Babel & Source Maps

Browserify lets you require('modules') in the browser by bundling up all of your dependencies.

browserify

Let's look at the basics of setting up Gulp and Browserify. Creating a Gulp task from scratch, we'll cover how to utilise the Browserify API to generate a single `bundle.js` file, catch and log any errors that occur in the compilation process, transform the stream into a format that can be consumed by `gulp.dest` and finish by writing the bundle to a `dist` directory.

Gulp and Browserify - Initial Setup

A brief introduction to using GulpJS in your JavaScript application and creating your first Gulp task.

Installing and Writing a Default Task with Gulp

Beginning with a single Gulp task capable of generating a one-time Browserify bundle, we enable file-watching and incremental rebuilds by incorporating Watchify. We add a second task `watch` & refactor our initial code to enable the bulk of it to be re-used. We’ll look at exactly how to ‘wire’ these tools together and how the relationship between Watchify & Browserify can manifest into a seriously efficient workflow.

Gulp and Browserify - Hooking up Watchify

We will look at bundling your JavaScript files using Gulp, Gulp-Concat, and Gulp-Uglify

Bundling Your JavaScript Files with Gulp

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. 