Learn Aria, Jwt and Serverless

WAI-ARIA, the Accessible Rich Internet Applications Suite, defines a way to make Web content and Web applications more accessible to people with disabilities. It especially helps with dynamic content and advanced user interface controls developed with Ajax, HTML, JavaScript, and related technologies. 

aria

We'll go over the work it takes to use ARIA to show why Semantic HTML is almost always the safer bet. 

Create a Semantic Checkbox vs an ARIA Checkbox

Debug Computed Accessibility Properties with Chrome Dev Tools

In this lesson, we use the element inspector in Chrome to test and improve our contrast to meet WCAG AA Contrast Ratio Standards.

Resources:
- [WebAIM - Contrast and Color Accessibility](https://webaim.org/articles/contrast/)

Debugging Accessible Contrast with Chrome Dev Tools

In this lesson, we are creating the audio player interface more visually appealing using icons from the React Icons library and Font Awesome, in this process, we are also ensuring that the interface remains accessible to screen readers by providing text descriptions for the icons, first by using the `title` prop on each icon, and then by implementing a `visually hidden` technique that hides the text descriptions from sighted users but makes them available to screen readers. This involves copying and pasting some CSS code to create a visually-hidden class, adding an `aria-hidden` attribute to each icon, wrapping each icon in a React fragment, and then adding a `span` element above each icon with the corresponding text description and the `visually-hidden` class.

**Think about:**  
- Why use `aria-hidden` or visually hide spans? 
- What value does this add to screen reader users?

Design Accessible Buttons Using Icons

In this lesson, we will create event listeners for the play and pause events on an audio player element and use these listeners to update the value of a variable called `isPlaying` that tracks the current state of the player (e.g., whether it is currently playing or paused). The event listeners, named `onPlay` and `onPause`, will be triggered when the user presses the play or pause button on the audio player element itself, not on a custom play button that may have been created.

Add Play and Pause Events to the Audio Player

We are creating an input of type range with an associated label, this input is to represent the current playback position in the audio, and the user will be able to change the playback position using the input.

The input value is set to be the media time state, it is added a minimum value of 0 and a maximum value as the duration. The demonstration shows how the media time state updates accordingly when the user changes the time using the input range.

A function called `onScrubberChange` is added, which takes in an event as an argument and `console.logs` the value of that event. The `onChange` event is added to the input, ensuring it works as expected. A variable sets the media time state and the current time on the audio ref.

**Think about:** Why do we use the `event.target.value` to set the new `mediaTime` (reminder that the value of the range is bound to `mediaTime`....maybe take a look at that with the formatter)

Create the Audio Scrubber to Control Playback Position

In this lesson, we are creating a new state called `mediaTime` with an initial value of 0, updating sample text in the markup to display the value of `mediaTime`, and adding an event listener to the audio element for the `timeUpdate` event.

In the `timeUpdate` event listener callback function, the `mediaTime` state is set to the audio element's current time, which can be accessed using the `audioRef.current.currentTime`. A function is added to the `onTimeUpdate` event of the audio element, to be able to track the current time. And a time formatter is added to format the time for displaying elapsed time and total time.

**Think about:** How often does onTimeUpdate update? (every second, not every millisecond) 

Tracking Audio Playback Progress by Adding Elapsed Time 

We created a duration state with an initial value of zero, then added an event listener to the audio element for the `loadedMetaData` event. In the event listener callback function, you set the duration state's value to be the audio element's current duration. This ensures that the value of the duration state is only set once the audio element metadata is loaded, allowing you to display the accurate total time of the audio file.

**Think about:** Why do we need to set the duration on the `onLoadedMetadata` event?

"The `onLoadedMetadata` event occurs when metadata for the specified audio/video has been loaded." You can read the docs [here](https://www.w3schools.com/tags/av_event_loadedmetadata.asp) 


 Implementing a Duration State 

JavaScript® (often shortened to JS) is a lightweight, interpreted, object-oriented language with first-class functions, most known as the scripting language for Web pages, but used in many non-browser environments as well such as node.js or Apache CouchDB. It is a prototype-based, multi-paradigm scripting language that is dynamic, and supports object-oriented, imperative, and functional programming styles.

javascript

Do you want to allow users of your app to create an account and sign in with their Google profile? If so, this 10-minute video will show you how to set up within your Auth0 tenant! 

The Google social connection allows users to log in to your application using their Google profile. By simply adding the connection within your Auth0 dashboard, enabling it for your application, and creating a project within your Google developer console, you can be up and running within no time!

How To Add Google Authentication with Auth0

JSON Web Tokens are an open, industry standard RFC 7519 method for representing claims securely between two parties.

Now that we have both the user and the token we can encode a JWT. This is made easy by the `jsonwebtoken` library that we will be using. 

To create a function that encodes a jwt, the function will need the user and token. Inside the function, definition create a `jwtPayload` object that just contains the essential data for encoding. Then, pass the payload to the `jsonwebtoken` library `sign` method and return the signed token.

Finally we store the jwt in the user's localStorage.

Encode User Data with JSON Web Token (JWT)

Now that we have our encoded JWT we need to be able to decode it!

The `jsonwebtoken` library makes this very easy. All we have to do is pass the `jwt` and our `token` to a decoder function. In that function definition we pass the arguments into the `verify` method and return the result.

Identify Users with JWT

We are going to use our JWT to make a protected request. 

All we have to do is create a button with a click event that calls our `fetchRepos` function. In the fetchRepos function make a fetch request to the `/repos` endpoint. In the fetch, pass an Authorization header with your JWT as a Bearer token. Then just await the response!

Use JWT to Make a Protected Request

We are going to simulate user verification when making a protected request. To simulate the database we are just going to use a simple array.

We verify the user by grabbing the JWT off of the authorization header in the request. We then look for a user in the database with a matching JWT. If the verification is successful we can give the user the data they requested.

Handle a Protected Request with JWT

 Every developer who has attempted to demystify OAuth 2.0 must be presented with mind-bugging complicated flow diagrams. It becomes worse when you try to understand all the terminologies of OAuth 2.0 and Open ID protocols.

There is no getting around the OAuth 2.0 flow being complicated with back and forth between your browser, the service you are authenticating with, and the application you want to access. 

This course gets straight to the point without any application code distracting you from the core takeaway -- You will learn how to authenticate and authorize yourself using GitHub as your Auth Server.

We'll first cover the OAuth 2.0 flow for authentication and then integrate the Open ID protocol for authorization.

[**LIVE EVENT**: Register here for a live webinar with Christian on OAuth.](https://egghead.zoom.us/webinar/register/WN_Sxy1FEcoTea8UA6F7EDzLw) Bring any questions you have from taking this course!

Add Github Login to Your Web App with OAuth 2.0

In this video you'll learn how to deploy a React app to AWS using AWS Amplify Hosting's drag and drop folder functionality. The app will also automatically be globally distributed on AWS's global CDN.

Deploy a React App to AWS in 24 seconds

Sometimes it's beneficial to add more context for a form field than can be provided by the label. In this lesson, we'll create the `.field-description` class to enable an additional field description. And we'll learn how to ensure users of assistive technology also receive the description in context by associating the description to the field with `aria-describedby`. This text span can also be used to provide validation messages.

Create and Style an Accessible Field Description

Accessible Rich Internet Applications Suite — WAI-ARIA — defines a way to make Web accessible to people with any type of disabilities and it’s also a good practice for skeleton loaders.

Attributes such as `tabindex`, `role`, and `aria-*` are essential for assistive technologies such as screen readers. So that, users with any type of visual disabilities can understand that the specific state of the fragment of your page is currently loading, having that validated by using different tools, such as Lighthouse integration via Chrome Devtools, as an example.

Use WAI-ARIA Attributes to improve Web Accessibility of your Skeleton Loader

Test web accessibility using the axe browser extension in Chrome, Firefox or Edge. Axe is an accessibility testing engine for websites and other HTML-based user interfaces.

The tool will run on your site and sort the errors it encounters in order of performance from Critical down to Minor. When you select issues, you'll get a detailed page of of what went wrong and how you can fix it.


Test Web Accessibility Using the Axe Browser Extension

Test web accessibility using the WAVE Web Accessibility Evaluation Tool. WAVE is developed and made available as a free community service by WebAIM. 

With the WAVE tool, you can test for accessibility directly in the context of the page. You'll be able to click on errors that you have to learn more about it, why it matters, and how to fix them.

In addition to a detailed summary of the issues on your page, WAVE has tabs for structure and color contrast to give you a detailed view of how your page is doing with both issues 



Test Web Accessibility Using the WAVE Browser Extension

Learn to test for accessibility using Google's Lighthouse tool -- an open-source, automated tool for auditing web pages.
Lighthouse can audit with quite a few different tests (SEO, performance, PWA, etc.). We will only be looking at the Accessibility portion. The audit will show any issues that the site has with links to learn more as well as which elements specifically failed the tests.  


Test Web Accessibility using Lighthouse

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

In this lesson, you'll discover how to style View Transitions using CSS pseudo-selectors to create custom animation effects. We'll transform the default cross-fade into a smooth slide transition by targeting the ::view-transition-old and ::view-transition-new pseudo-elements. You'll learn how these powerful selectors give you precise control over your transition animations, allowing you to create more engaging and personalized user experiences with just a few lines of CSS.

Customize View Transitions with CSS Using view-transition-old and view-transition-new

In this lesson, you'll learn how to implement smooth state transitions in your web applications using the browser's built-in View Transitions API. We'll create a simple example that demonstrates how to animate between different text states with just a few lines of code - no external libraries required. This powerful native API makes it easy to add professional-looking transitions to your user interface, enhancing the user experience with minimal effort.

Create Smooth UI Transitions with the Native View Transitions API

I've been using Cursor for a very long time and their "Agent" feature in Composer is fairly new, so I'm still getting used to it. But since Windsurf recently got onto the stage with their Cascade agent, they've slowly been gaining the mind share on the UX for coding agents. I decided to put them to the test by putting Windsurf and Cursor on the exact same screen side by side trying to accomplish the same task and to see which workflow I would prefer. I've been a diehard Cursor user for over a year now, so it's going to take a lot for me to switch to a different IDE. But I just have to say, even from this simple demo, Windsurf is looking pretty nice.

This lesson is just going to walk through creating a CLI using both tools to print out inspirational quotes and to explore how they approach the step-by-step of installing packages and running commands and setting up all the files we need to get this running.

Windsurf Cascade vs. Cursor Composer Agent Side-by-Side Comparison

This TypeScript tutorial explains how to use generics, allowing for different types to be passed as arguments. It discusses the use of shorthand syntax in generics and illustrates with examples. This method is useful for library creation, providing type safety and control to the user.

```typescript
interface PhotoMetadata<T> {
  title: string;
  takenAt: Date;
  customData: T;
}

// Function that processes a photo with custom metadata
function processPhoto<T>(photo: PhotoMetadata<T>): {
  processedTitle: string;
  daysSinceCapture: number;
  customDataSummary: T;
} {
  const today = new Date();
  const daysSinceCapture = Math.floor(
    (today.getTime() - photo.takenAt.getTime()) / (1000 * 60 * 60 * 24)
  );

  return {
    processedTitle: photo.title.toUpperCase(),
    daysSinceCapture,
    customDataSummary: photo.customData
  };
}

// Example usage with different custom data shapes
type CameraSettings = {
  iso: number;
  aperture: string;
  shutterSpeed: string;
}

type LocationData = {
  latitude: number;
  longitude: number;
  locationName: string;
}

// Using with camera settings
const photoWithCamera: PhotoMetadata<CameraSettings> = {
  title: "Sunset at beach",
  takenAt: new Date('2024-01-15'),
  customData: {
    iso: 100,
    aperture: "f/2.8",
    shutterSpeed: "1/1000"
  }
};

// Using with location data
const photoWithLocation: PhotoMetadata<LocationData> = {
  title: "Mountain vista",
  takenAt: new Date('2024-02-01'),
  customData: {
    latitude: 45.5231,
    longitude: -122.6765,
    locationName: "Mount Hood"
  }
};

const processedCameraPhoto = processPhoto(photoWithCamera);
const processedLocationPhoto = processPhoto(photoWithLocation);

processedCameraPhoto.customDataSummary.iso
processedLocationPhoto.customDataSummary.longitude

```

Basic Explanation of Typescript Generics

A very basic explanation of generic function arguments

I've been using Cursor as my primary editor for over a year now, but recently I've heard wonderful things about Windsurf AI Agent features. I decided to record myself building out something I've always wanted to make, but never made the time for.

In this lesson, I demonstrate how to leverage Windsurf's powerful agent process to create a fun word-guessing game inspired by Heads Up. Watch as I build an interactive application featuring category selection and word navigation, complete with data hosting on GitHub Gists and deployment to GitHub Pages - all in under 30 minutes (before editing the lesson down to 12 minutes)!

What makes this project particularly exciting is how Windsurf eliminates the typical friction points of development. While this game was always on my project wishlist, the overhead of setup, configuration, and deployment made it hard to justify the time investment. Windsurf's agent process handles all these pain points seamlessly, from managing URLs to orchestrating deployment.

This lesson perfectly showcases how AI agents can help developers bring their backlog of project ideas to life, transforming what would typically be time-consuming tasks into efficient, enjoyable development experiences.

Build a Word Game with Windsurf's Cascade AI Agent



Discover how to harness the power of Cursor IDE's Composer Agent feature to optimize your code. In this lesson, you'll witness an AI agent doing all the work to generate test suites, implement performance benchmarks, and create optimized function variations - all without writing a single line of code. You'll learn how to validate performance improvements through data-driven benchmarking, ensuring that optimizations are backed by concrete metrics rather than speculation. This hands-on demonstration showcases a groundbreaking approach to automated function development that combines the precision of test-driven development with the efficiency of AI-powered optimization.


Agent-Driven Development in Cursor: Testing, Benchmarking, and Optimizing Functions

This course is aimed for using `zod` effectively in projects based on TypeScript (both browser and node.js). The benefits you gain with this course is not just simply coding, but also understanding when/why/how should you perform runtime validation.

`zod` is the missing piece to TypeScript's capabilities, which can guarantee type-safety only in compile-time.

`zod` can be used whenever the compiler cannot guarantee what happens in runtime. And... it's a very frequent usecase, such as HTTP calls, websockets, etc.

In this course you get quickly up and running by:
1. using `zod` with primitives and objects
2. adapting `zod` quickly to existing projects thanks to automatic generators
3. changing the strategy frm type-first to schema-first
4. using error-throwing `parse` or non-error-throwing `safeParse` basing on your needs
5. applying `zod` to the most common usecase - validating API responses
6. handling errors the most convenient way (out of many!)

Take advantage of runtime validation with `zod`. Take advantage of the detailed lessons in this course 🔥

Effective Runtime Type Checks with Zod


Cursor can now automatically run commands in the terminal and walk step-by-step towards building out your entire project. You give it a goal, then it will suggest the commands you need to run and the files that you need to create and you can work with it to achieve what you're building. This lesson does a quick walkthough of using a Cursor Agent to build a project from scratch and guide it along the way. Cursor Agents definitely feel like a sneak peek at the future of programming!

Cursor Agents Initial Impressions - Allow an AI to Build Your Entire Project

Mock Service Worker is an API mocking library that allows you to write client-agnostic mocks and reuse them across any frameworks, tools, and environments.



Mocking WebSocket APIs with Mock Service Worker


While using anonymous functions might seem convenient, they can create difficulties when trying to identify performance bottlenecks during profiling. This lesson will demonstrate how named functions make it easier to pinpoint and address performance issues, ultimately leading to more efficient and debuggable code. Learning this practice will greatly improve your ability to locate and fix performance issues in complex projects.

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