Protocols of API

What is API protocol?

An API (Application Programming Interface) plays an intermediary between program and application. It further enables them to communicate with each other. This interaction is performed through a set of programs based on a set of rules called protocols. Protocols determine the execution of a program. Protocols are also understood as a standard mechanism for data communication.

Web API protocols

As mentioned above that API serves as the bridge between two applications or more than two applications. On the web, APIs provide communication and are thereby called web services and follow web protocols for data transmission. API’s role is to ensure that requests and responses are understood and according to the protocols. Due to the above reason, protocols are followed. The primary protocol of the web API is HTTP (Hyper-Text Transfer Protocol). Another essential instrument besides protocol is ‘format’.

HTTP protocol

Many web browsers, also referred to as clients, use HTTP (Hyper-Text Transfer Protocol) to communicate with web services. HTTP is request-response protocol. The client sends a request to the server, and the server responds with the desired result. The HTTP is adopted as the standard protocol of APIs. Due to the advantages of HTTP, a large number of developers prefer HTTP protocol.

The advantages of HTTP

Most developers are familiar with this protocol, so it is easy to scale and update.
Due to the little processing required by the software, it is faster among other protocols.
Responses can be cached, meaning that repeated commands are processed faster.

Process of HTTP protocol:

The data exchange between the two is not in plain files; it is written in HTML format. In this format, data is transferred to the internet. The process completes in three steps. The first step includes a request sent by browser, its URL and method, and protocol version. In the second step, a server receives the request and runs a program to process it. In the last step, the server returns the HTTP response to the browser.

The structure of HTTP requests comprises four major components: URL, method, headers, and body. The structure of HTTP responses, on the other hand, includes status quo, headers, and body. Moreover, HTTP is the standard protocol for REST APIs.

Formats for Data Retrieving:

Web APIs typically make HTTP requests and receive data in the form of XML and JSON responses.

XML Format

XML is the acronym of Extensible Markup Language, and it is similar to HTML. HTML is the language that is used by HTTP for data maneuvering. The role of XML is to store and transport data. Contrary to the HTML protocol, XML does not make changes in data. It only retrieves data. As far as data exchange is concerned, XML is convenient. It is an extensible language and works on tags. Tags further help in interpreting the received data.

JSON Format

Likewise, JSON is another format to store and transport data. The syntax of JSON is different from that of XML. JSON uses pairs, while XML uses tags for data storage. Both SOAP and REST employ HTTP, XML, and JSON for data management.

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