Category: 02. Koa Js

Caching is the term for storing reusable responses in order to make subsequent requests faster. Every browser ships with an implementation of a HTTP cache. All we have to do is ensure that each server response provides correct HTTP header directives to instruct the browser on when and for how long the response can be…

Compression is a simple, effective way to save bandwidth and speed up your site. It is only compatible with modern browsers and should be used with caution if your users use legacy browsers as well. When sending responses from the server, if compression is used, it can greatly improve the load time. We’ll be using…

Authentication is a process in which the credentials provided are compared to those on file in the database of authorized users’ information on a local operating system or within an authentication server. If the credentials match, the process is completed and the user is granted authorization for access. We’ll be creating a very basic authentication…

HTTP is stateless, hence in order to associate a request to any other request, you need a way to store user data between HTTP requests. Cookies and URL parameters are both suitable ways to transport data between the client and the server. However, they are both readable on the client side. Sessions solve exactly this…

Cookies are simple, small files/data that are sent to client with a server request and stored on the client side. Every time the user loads the website back, this cookie is sent with the request. This helps keep track of the users actions. There are numerous uses of HTTP Cookies. To use cookies with Koa,…

Static files are files that clients download as they are from the server. Create a new directory, public. Express, by default doesn’t allow you to serve static files. We need a middleware to serve this purpose. Go ahead and install koa-serve − Now we need to use this middleware. Before that create a directory called public. We will store all…

eb applications need to provide the functionality to allow file uploads. Let us see how we can receive files from the clients and store them on our server. We have already used the koa-body middleware for parsing requests. This middleware is also used for handling file uploads. Let us create a form that allows us…

Forms are an integral part of the web. Almost every website we visit offers us forms that submit or fetch some information for us. To get started with forms, we will first install the koa-body. To install this, go to your terminal and use − Replace your app.js file contents with the following code. The…

Pug is a templating engine. Templating engines are used to remove the cluttering of our server code with HTML, concatenating strings wildly to existing HTML templates. Pug is a very powerful templating engine, which has a variety of features such as filters, includes, inheritance, interpolation, etc. There is a lot of ground to cover on this.…

Middleware functions are functions that have access to the context object and the next middleware function in the application’s request-response cycle. These functions are used to modify the request and response objects for tasks such as parsing request bodies, adding response headers, etc. Koa goes a step further by yielding ‘downstream’, then flowing the control back ‘upstream’. This effect…