Learn Angularjs, Babel and Chai

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

We take the opengraph image we wrote in codesandbox and copy it into our serverless function. We use Rollup to compile the component into an IIFE (immediately invoked function expression) that can run in our headless browser environment and cover a wide set of rollup plugins that we need for compatibility. We end the lesson having successfully screenshot our opengraph react component from our Netlify Function

**Note**:  Due to Netlify changing their handling, the path in `fs.readFileSync` is affected. Update to:
```js
const script = fs.readFileSync(path.resolve(__dirname, "image.js"), "utf-8");
```

Compiling a React to an IIFE with Rollup to execute and render in a headless browser

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

When migrating AngularJS (v1.x) applications to Angular you [have different options](https://github.com/angular/ngMigration-Forum/wiki/Migration-Paths-Overview). Using Angular Elements is one of them. In this lesson we learn how to integrate an Angular Element into an AngularJS (v1.x) application. We will leverage some features release in the latest AngularJS 1.7.3 that make it fully compatible with custom elements.

Use Angular components in AngularJS applications with Angular Elements

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

In this lesson, we'll configure webpack to use the Babel loader for our JavaScript files, allowing us to transpile our source files and generate a bundle for deploying our application.

Configure webpack to Load JavaScript Files through Babel with babel-loader

Converting all of our modern JavaScript into ES5 compatible syntax is a great way to use modern features while targeting older browsers. What happens when the browsers natively support these language features? Then it no longer makes sense to transform that code or to include polyfills that will go unused. In this lesson, we’ll add the `@babel/polyfill` package and configure `babel-preset-env`

Target specific browsers with babel-preset-env and the babel pollyfill

We transpile our JavaScript code so we can use modern language features, even if browser support isn't quite where we need it to be. This includes proposed features that aren't yet part of the official language specification. In this lesson, we'll see how we can support the proposed class property syntax for JavaScript with a Babel plugin.

Support Proposed JavaScript Features with Babel Plugins

One approach to building high performance applications with `webpack` is to take advantage of code-splitting to only load the needed JavaScript on initial load and asynchronously load additional JavaScript bundles when needed. In this lesson, we'll create add some code-splitting to our placeholder application and configure our project to support the dynamic `import()` syntax.

Asynchronously Load webpack Bundles through Code-splitting and React Suspense

In this lesson, we'll add React and ReactDOM to our project and create an entry point for the React application. We'll also configure Babel with the React preset so Babel can transpile our JSX into JavaScript that will run in a browser.

Configure babel for React with preset-react

In this lesson, we’ll install Babel and use it from the terminal to see how it can take JavaScript that uses modern language features and output JavaScript that will run in down-level browsers.

Transform Modern JavaScript Features with Babel

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

Many times while building an AngularJS application you'll need to manipulate data, and it doesn't make sense to do it with a Controller method. Luckily you have Filters, which are particularly well suited for manipulating text within your HTML views. This handy tool uses a simple syntax to create highly reusable functionality for your apps.

Filters

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

chai

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

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

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

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

Manually creating action items every time we need to dispatch an action eventually accumulates to a very tedious process. In this lesson, we will learn how to abstract out the creation of action items so that we consolidate their creation into a single place. This not only creates efficiencies in how we express code but also reduces code volume while simultaneously increasing stability. 

Angular 1.x Redux: Create Reusable Actions with Action Creators

In this lesson, we are going to learn how to enable our store to work with more than one reducer in an application.

Currently, we have set up our store to work with the categories reducer exclusively, but this leaves us with a real problem, what if we want to keep track of the currently selected category within our store so that we can access that data somewhere else in the app? It is safe to say that most applications consist of many data models interacting together, and we need a way to accommodate this within the single state tree in our application.

When we initialize our app store, wouldn't it be convenient if we could take all of our reducers and combine them into one big reducer that our store knows how to work with? Well, this is exactly what the combine reducer method does in Redux. It allows us to combine reducers together and then access them as a named property on our application store.

We currently have a category reducer just hanging out here doing nothing because we have been focusing entirely on the categories reducer. We are going to combine the two reducers so that we can use the current category data within our bookmarks component.

Angular 1.x Redux: Handle Multiple Models by Combining Reducers

Invariably the question that comes up when talking about Redux is how does one handle asynchronous operations in redux. For instance, how do we hand off an operation to redux that requires a remote call to the server? Where exactly does the async part get handled? 

Redux has this concept of middleware that allows us to insert custom logic in the space between dispatching an action, and the moment it reaches the reducer. In this lesson, we are going to set up a few async operations and then use redux thunk middleware to make sure that everything makes it into the reducer properly.

The main key to thunk middleware is that it allows us to return a function instead of an action. This function can encapsulate the async operation and dispatches the appropriate action when the operation is completed.

Angular 1.x Redux: Handle Asynchronous Operations with Middleware

One of the primary advantages of using redux is that reducers are incredibly easy to test. By nature, they have a clearly defined contract of inputs and outputs, and because they are stateless, they require very little instrumentation to test in isolation. 

We will start with a few simple tests for the categories reducer and then move on to testing the CRUD functionality within the bookmarks reducer. 

Angular 1.x Redux: Test Reducers

Up to this point, we have created an effective, yet rudimentary, implementation of Redux by manually creating an application store, reducers and action creators. We have already made significant progress in simplifying state management within our application, but we have in fact only touched the surface of what Redux has to offer.

In this lesson, we are going to introduce ngRedux into our application and let it handle the rest of the heavy lifting as we work through this series. ngRedux is a project that provides angular bindings to redux to streamline integrating it into our application.

Angular 1.x Redux: Integrate ngRedux

In this lesson, we are going to learn how to integrate Redux Devtools into our Angular application.

Redux Devtools is a live-editing time travel environment for Redux. Devtools boasts a list of awesome features but my two favorite ones are that we can inspect every state and action as it happens and we can go back in time by “cancelling” actions.

This is going to be an interesting lesson because, in order for this to work, we are going to need to make something that was written for React work in Angular. For the most part, everything will play side by side with one small trick that we will pull off at the end to force an Angular digest cycle when React manipulates the application store. 

Angular 1.x Redux: Integrate Redux Devtools

One of the biggest mental shifts that developers have to take when embracing redux is shifting from mutable operations to immutable operations. The problem with mutable operations is that they create side effects that involve anything else that is referencing the thing that is being mutated.

With immutable operations within a reducer, a new object is returned for every operation – completely bypassing the possibility that an existing reference is going to be compromised. It is then up to the consumer to decide how they want to get the new data and what to do with it.

In this lesson, we are going to flesh out the CRUD functionality of our bookmarks reducer, doing it first using mutable operations and then refactoring it to use immutable operations.

Angular 1.x Redux: Avoid State Mutation with Immutable Operations

In this lesson, we are going are going to apply everything that we have learned by building out our bookmarks component to be powered by Redux. This will help reinforce all the techniques we have covered by seeing them built out  in a single, contiguous lesson.

We will walk through the steps necessary to phase out the bookmarks model with a Redux implementation that includes building and integrating the equivalent reducers and action creators to integrate into our application.

Angular 1.x Redux: Put It All Together

In this lesson, we are going to learn how to map our Angular component directly to our application store using the connect method on ngRedux. 

In Angular, it is a common technique to bind a controller property directly to the model so that our controllers remain lightweight and operate more as a pass through mechanism than anything else.

Using the connect method, we can accomplish the same effect by not only binding properties directly to the application store, but also binding our controller to our action creators. This allows us to drastically simplify our controllers as we are able to delete a bunch of local controller methods as they become unnecessary because of our mappings.

Angular 1.x Redux: Map State and Dispatchers to Redux

In this lesson, you'll learn how to enhance the accuracy of components generated by Cursor Composer by aligning your project's package.json with Cursor's rules. We'll guide you through extracting the list of installed packages from your package.json and incorporating them into your .cursorrules file, along with brief descriptions of their functionalities. By providing Cursor with this contextual information, you'll enable it to generate components that are more precise and functional on the first attempt. The lesson includes demonstrations of component generation both with and without these enhancements, highlighting the improvements in accuracy and efficiency.

Boost Cursor Composer Accuracy: Integrating package.json with Cursor Rules

Speed up your bug-fixing process dramatically with Cursors Composer. Take a warning from your logs, search for relevant terms, then seamlessly import both the warning and search results into Composer. Add documentation and apply fixes to all search results in one go. This streamlined workflow resolves multiple issues rapidly, saving valuable development time.

Batch Fix Every File in Search Results with Cursor's Composer

 We map over the initial set of results then use `Promise.all` to efficiently fetch the details of each pokemon rendered in the table. This allows us to add more columns to our pokemon table.

Fetch and display row details with Promise.all in Tanstack Table

map over the initial set of results then use `Promise.all` to efficiently fetch the details of each pokemon rendered in the tanstack table

Create a custom hook to fetch remote data by passing a promise to the React 19 `use` hook. Then render this data in Tanstack Table by memoizing the results and passing them to `useReactTable`.

Render remote data in a Tanstack Table with React 19's use hook and a promise

Create a custom hook using React 19’s use to fetch data with a promise. Render it in a Tanstack Table by memoizing and using useReactTable.

You know when you're deep in the code trenches and need someone to challenge your assumptions? That's exactly what this is about.

Instead of waiting for someone to poke holes in your master plan, you can paste that strategy straight into AI Studio and let it pressure test your ideas. We're talking about using this tool to validate everything from your feature proposals to your ambitious refactoring strategies.

The real magic happens when you hit that microphone button. Now you're in a real-time verbal sparring match. It's like rubber duck debugging but the duck actually pushes back and makes you defend every architectural decision you've made.

Here's the workflow:
1. Drop your master plan into the system instructions
2. Tell the AI to challenge every assumption
3. Hit that mic and defend your choices like you mean it
4. Watch your plan either emerge stronger or get rightfully dismantled

This approach is perfect when you're:
- Stuck in your own head with a complex problem
- Need to validate if your approach holds water
- Want to catch edge cases before they catch you
- Looking for opportunities you might have missed because you're too close to the code

It's like having a senior dev on call 24/7, ready to challenge your ideas and push you to think deeper about your solutions.

Now go forth and get your ideas challenged. Your projects will thank you for it.


An Uncomfortable and Challenging Conversation with AI Studio

In this lesson, you'll learn how to effectively brainstorm your project ideas before working with AI agents. We'll cover:

1. The importance of having a clear plan before starting work with AI agents
2. Using traditional brainstorming techniques to gather your thoughts
3. Leveraging video recording to capture your brainstorming session
4. How to review and analyze websites for inspiration
5. Documenting likes, dislikes, and potential features for your project
6. Using AI tools (like AI Studio) to organize and process your recorded brainstorming session

The lesson emphasizes a modern approach to brainstorming that combines traditional techniques with video recording, making it easier to later process your ideas through AI tools. This method helps ensure that no ideas are lost and that your thoughts can be effectively organized by AI for future reference.

How to Brainstorm Your Project Features to Prepare for AI Agents

fast-check allows us to create composite generators that suit our testing needs. We'll generate two numbers to create a point simulating an X and Y and assert that the distance should always be greater than or equal to 0.

Generate composite objects with fast-check fc.record

Just using fast-check by itself can make you tests verbose and tough to read. Lucky for us there are many integrations with fast-check such as the `@fast-check/jest` package that will help remove some boilerplate from our test.

Tidy up your test with @fast-check/jest

Many people share .cursorrules files, but trying to craft your own from scratch is a huge pain. Instead, this lesson shows you how to grab ALL community-created .cursorrules files to build a custom rule set for your projects. We'll use Gitingest and Google AI Studio to gather these examples and generate an awesome starting point customized to your specific project.

Generate Custom .cursorrules for Your Project Based on Community Examples

The GitHub CLI allows you to search issues and filter on different criteria like amount of comments. This allows you to search for real-world situations and pains/solutions people have using different technology. 

With the GitHub CLI in hand we'll drop 100s of issues as context in Googles AI Studio and have Gemini determine the 10 most frequently asked questions. This will give us a sense of how people use a library and where people get hung up.