Getting Started with Koa Js..
Koa is a new web framework designed by the Express team that promises to be a more advanced foundation for online apps and APIs. Because ES6 generators are such an important part of Koa.js, an app written using it will have far fewer callbacks. A Koa application is a collection of middleware functions that are executed in response to requests.
Why is Koa Js?
A Koa application is a stack-like object that contains an array of middleware generator functions that are constructed and performed on demand. Many other middleware systems, such as Ruby’s Rack, Connect, and others, are similar to Koa. However, providing high-level 'sugar’ at the normally low-level middleware layer was a significant architectural decision. This increases interoperability and robustness while also making middleware development more pleasurable.
Koa Project Initialization
To begin, make sure Node.js is already installed on your system. Then you must create and enter a folder for your project. Then run ‘npm init’ to build up the structure of your project. You’ll need Koa, as well as ‘@koa/router’ for routing and ‘koa-bodyparser’ for passing data.
The development server must now be started. Before we start, we need to create the app.js file and add the code section that the development server requires. In your root directory, create a file called app.js.
After including this code section in your app.js file, you may run the server by running ‘npm run dev’ in your code editor’s terminal. This will result in the following output:
Let’s get our API up and running. We’ll create a little application that allows us to create, edit, and delete posts. We must create an api directory within our root directory to include the functions required for those CRUD actions.
Instead of using a database, we’ll record data using a Map object. As a result, the functions will be as follows:
Then, for each function, we must define routes. As a result, you’ll need to create a router folder to keep track of all of the routes you’ll be taking to do these tasks.
Any Koa app’s foundation is “Ctx.” It handles requests in a stack-like manner. It’s comparable to other frameworks like Express, which uses a chain of middleware to process incoming requests. The context object (ctx) is used for a variety of activities, including conveying the body to input data and providing parameters.
After you’ve created all of the required functions, you’ll need to change app.js to make all of these crud activities work.
Now you can test whether these routes are working as intended by running the server. Check if it’s functioning with postman or insomnia (https://localhost:3000/posts).