REST API

REST APIs are APIs with a set of rules that developers can follow to create APIs and get a response APIs and a management board .

Representative State Transfer, or REST, is positioned as a Representative State Transfer . It is also called RESTful API .

Rest API allows defining standards on how files or devices can be connected, how parts can communicate, and how the code in the peripheral areas can be changed without affecting the operation of the server and how the code across the server can be changed without affecting the overall operation.

REST APIs communicate via HTTP requests to perform database functions such as create record, read, update and delete within a resource. It uses these four basic requests, such as GET, POST, PUT, and DELETE.

REST APIs support almost any programming language. The only condition is that they comply with 6 REST principles. These principles are: Single type interface, client-server autonomy, no state information, cacheability, layered system architecture, and optional code structure.

REST API Terminology

• Client: A hardware or software that initiates communication, using the API made accessible by the server. For example, when you visit Twitter, the client is the one that requests the browser to send a request to the Twitter API and to see various pieces of information on the screen.
• Resource: Any content that the server can provide to the client. This content could be a text file, image, or video. For instance, in the Instagram API, a resource could be the photos uploaded by the user or hashtags.
• Server: The system containing the resources the client requests.

How do REST APIs Work?

1. The Client sends a request to the server using the API. Accordingly, it communicates with the server. 
2. The API documentation of the server applications explains how the client is supposed to use the REST API.
3. The server examines the request of the client and accepts its approval. 
4. The server approves the request and processes it.
5. The server sends a response to the client. The response contains the information needed by the client. Thus, the process is completed flawlessly.

What are the Requests Used During REST?

RESTful APIs are usually implemented using HTTP. An HTTP method tells the server what to do with the resource. The HTTP requests used during Rest are as follows;

• GET: Clients use GET to view and list data on the server in a particular order.
• POST: Clients use the POST request to add data to the server. In other words, this request is used to create a resource.
• DELETE: Allows deleting unnecessary data and resources.
• PATCH: Clients use the PATCH request to update data and resources on the server.

What are the Authentication Methods of RESTful API?

Before sending a response, RESTful service clients should authenticate their identity to the server to establish trust. There are four authentication methods. These are; HTTP authentication, basic authentication, bearer authentication and API keys.

For HTTP authentication, it uses basic authentication and bearer authentication methods. In basic authentication, information such as username and password is sent to the client. In bearer authentication; the client sends access control information to access resources.

API keys are another method used for REST API authentication. In this method, the server sends an API key to the client making the request for the first time, and the client uses this API key to access the data.
 

What are the Advantages of RESTful APIs?

REST APIs are widely used by many developers. Especially, the fact that REST allows users to easily and flexibly connect to and manage cloud services leads to its preference.

RESTful APIs are used by leading technology companies in the world, such as Amazon, Google, LinkedIn, and Twitter. So, what are the advantages of RESTful APIs?

1- Scalability

Due to optimizing client and servers, scaling, arranging and managing servers on different platforms is easier thanks to REST.

2- Flexibility

REST APIs allow users to easily communicate between different servers.

As the usage of server broadcasting platforms or technology broadcasts does not affect its usage, its usage increases even more. Also, REST uses almost any form for data exchange. There are no strict rules.

3- Independence

REST APIs are independent of the technology used and allows parts to be independent sections of it.
 

REST API Principles

Client - Server Autonomy

REST API execution, execution, and server operate independently of each other. The client and server use different technology loads at this time. The independence of the client and server from each other increases the reliability and system structures.

Uniform Interface

It has the propriety of being used uniformly of the REST API which provides ease of use and a common standard understanding. That is, there is a standardized way of communication when executing and the server communicate. This feature is an important feature that distinguishes REST API from non-REST APIs.

Layered Architecture

REST API system has a connected structure. Each layer operates independently of the other. In this connection architecture, scalability is increased by placing a proxy associated with and found on the server. Also, by creating a separate layer for system security, the system is made more secure.

Caching

REST APIs perform caching processes and store data in the cache instead of asking for it repeatedly. This reduces the load on the server and enables the application execution sequence.

No State Information

REST API consists of layers and is independent of these layers. It also does not store any stockpiles related to previous records. Each session and request is handled independently of previous sessions.

Optional Code Structure

It has an optional code structure related to the drawing of the REST API. This is also called COD. The KEI allows the animals to control their features more. For example, when you fill out a registration / application form on a website and enter the information incorrectly, the browser notices this error and gives a warning. This feature is done by the operating code on the server side.