Introduction To Rest API: What Is It In Simple Words
The REST API is responsible for almost all interactions between server and client applications – let’s see how this technology works.
What Is REST API
Representational State Transfer (REST) in translation is the transfer of the state of the representation. The technology allows you to receive and modify the data and states of remote applications by transmitting HTTP calls over the Internet or any other network.
To put it simply, a REST API is when a server application gives access to its data to a client application at a specific URL. Next, let’s take a closer look, starting with the basic concepts.
Rest API Basic Concepts – HTTP Protocol And API
The Application Programming Interface (API ), or application programming interface, is a set of tools that allows one program to work with another. The API provides that programs can run on different computers as well. In this case, you need to organize the API so that the software can request each other’s functions over the network.
Also, the API should consider that programs can be written in different programming languages and run on other operating systems.
The REST API allows you to use the HTTP protocol (encrypted version – HTTPS) for communication between programs, with which we receive and send most of the information on the Internet.
HTTP is pretty straightforward. Let’s see how it works with an example. Let’s say there is an address http://website.com/something. It consists of two parts: the first is the site or server address, http://website.com. The second is the address of a resource on the remote server, in this example/something.
By typing the URL http://website.com/something into the address bar, we are going to the website.com server and requesting a resource called / something. “Go over there, bring me this,” is the HTTP request.
Now imagine that there is a program running at website.com that another program wants to access. For the program to understand what functions are needed, different addresses are used.
HTTP Methods: The Basics Of The REST API
Different ways of accessing it are used for the resource you are requesting to perform the required actions. For example, if you work with invoices using the / invoices resource that we came up with above, you can view, edit or delete them.
There are four classic methods in the API system:
- GET is a method for reading information. GET requests always only return data from the server and never change or delete it. In the accounting application GET/invoices, you open a list of all invoices.
- POST – create new records. In our application, POST/invoices are used when you make a new invoice for payment.
- PUT – editing records. For example, in PUT/invoices, you correct the invoice number, amount or adjust the details.
- DELETE – deleting records. In our application, DELETE/invoices delete old invoices that counterparties have already paid.
Thus, we get four functions that one program can use when accessing resource data; in the example, this is a resource for working with invoices.
What The REST API Is Used For
The REST API architecture is the most popular solution for organizing interaction between various programs. This happened because the HTTP protocol is implemented in all programming languages and operating systems instead of proprietary protocols.
The Most Commonly Used REST APIs Are:
- To connect mobile applications with server applications.
- For building microservice server applications- This is an architectural approach where large applications are broken down into many small pieces.
- To provide access to third-party programs. For example, the Stripe API allows programmers to embed payment processing into their applications.