Getting Started with APIs in JavaScript

What is an API?

So with APIs, you can integrate features, products, and services from already existing ones into your application without building them yourself.

Why you should use an API?

  1. It helps you integrate cool stuffs to your website: You can integrate cool stuff easily like payment gateways, google maps, authentication channels from popular sources like Google or Facebook, services from eateries, agriculture, health, movies, etc
  2. APIs are great time savers: APIs allow developers to save time by taking advantage of a platform’s implementation to do the nitty-gritty work. This helps reduce the amount of code developers need to write and also helps create more consistency across apps for the same platform.
Photo by Nathan da Silva on Unsplash

Getting Started???

When you have settled that, you can then proceed to find an API to suit your need. While there are free APIs available, you might need to pay to be able to use some, you can find free APIs here and here.

After settling for which API to use, go to the APIs documentation or website on how to use it.

In this article, I am going to be creating a web page that displays pictures of cute dogs(I don’t like dogs tho).

Here is the link to the documentation we’ll be using: Link

Home page of API documentation

Reading the API Documentation for information:

Most of the time, the documentation will include examples that you can tweak to get the output that you’re after.

Some APIs require you to sign up before using them mostly for authentication purposes and to track your requests. After signing up and confirming your email and then you can now locate your dashboard for your API key.

But in this case, we don’t need to sign up, we can just use the API straight away.

Getting an API key

Note that not all API requests for an API key, also your API keys is like a password that shouldn’t be shared with other people.

Like I mentioned earlier, we don’t need an API key for this article, just have that in mind for subsequent APIs you would be using.

Fetching/Requesting data from the API:

Here is my HTML file, we would be using JavaScript to generate data from the API :

HTML file

Since APIs work through a request and response method. You need to send a request using HTTPS and fetch(). This has become the standard way of calling APIs in JavaScript.

The fetch() method allows us to perform HTTP requests to a server. If we want to access the data, we require two .then() handlers. We first define the path (fetch), request data from the server (request), and define the content type(body) using the .then handler(call back), then finally access the data (response) using the .then() handler.

Here’s what I mean:

Applying the same method, we do this:

We can check the console in the Developer tool of the browser to see if it works

Displaying data on the browser

We’ll change that console.log to a function so we can use the data easily without running into any access errors. We will create an arrow function and use data as its parameter. Every other code henceforth should be written inside this function.

Since we just have one root element in the HTML file which is the .app div. We’ll access it using querySelector().

We would then use forEach() to display the pictures from the array of images, we want each image to be in a div and they should all be in the .app div.

Using createElements() We can create a div and give it a class name of card using className. Here is the code:

We would repeat the same steps to create an image element and set the source to the image URL from the API. I used a template string to avoid repeating the same code multiple times.

Okay great, we are done with that but this is only visible in the console, to make it show in the browser, we’ll append it to the .app div already in the HTML file using appendChild(). We’ll append the card div to the .app div and then the image to the .card div. Here's the code:

So far, this is what the code looks like:

And Viola! we are done.

To make it look better, let's add some CSS:

So here, you have been able to connect to an API and display the images from the API on the browser using DOM.

Glory Praise is a front-end web developer based in Nigeria. She writes about tech( and life.

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