APIs (Application Programming Interfaces) define a set of guidelines that enable software applications to interact and exchange data seamlessly. They are widely used today to help developers integrate data and services from other applications into their own. With APIs, developers can add various features using API calls without writing a lot of code.
A common example of API integration is payment gateways on eCommerce websites. After checkout, users can choose payment options like PayPal, Google Pay, or Paytm. When a user selects a payment method, they are redirected to the provider’s official website to complete the transaction. This process is made possible through APIs.
Protocols are the set of rules and standards that define how data is requested, transmitted, and received between systems. There are different types of API Protocols available. Understanding the types and their differences is crucial for the developers. Let’s have a look at different types of API protocols.
RESTful APIs
Restful APIs are among the most popular types of API used today. It uses Representational State Transfer (REST) Architectural style. They are used for the exchanging of data between systems over a network. This type of APIs uses a client-server approach.
A request is sent from the client to the server in the form of a url as HTTP GET, POST, PUT or DELETE request. These are the API Methods. API methods are the actions that can be performed in an API endpoint for different purposes.
* GET : Receives data
* POST : Creates data
* PUT : Edit/Updates data
* DELETE : Deletes data
* PATCH : Makes partial modifications to the data
Information from the REST APIs are delivered in several formats including JSON, HTML, XLT,
Python, PHP or Plain text. However JSON is the most popularly used format.
SOAP APIs
SOAP or Simple Object Access Protocol API, is a standard protocol for transferring data between systems via HTTP and XML. Using SOAP API you can send and receive data independent of language or platform. SOAP messages are XML documents that contain encoded data and structured tag elements such as:
* Message: Information exchanged between two SOAP nodes
* Envelope: The envelope encapsulates the XML document as a SOAP message, with the envelope tag designating the XML as a SOAP message.
* Header: Provides a title
* Body: The body tag holds the SOAP message's core, including the procedure name, parameters, and data.
* Fault: Information about the errors that occurred while processing the message.
RPC APIs
The remote procedural call (RPC) API is one of the simplest forms of API, which enables the communication between a server and a client remotely. In an RPC call, the client invokes a function on a remote server as if it were executing a local function. The client sends the necessary parameters to the server, which processes the request and returns the result. This seamless interaction enables distributed systems to communicate efficiently, abstracting the complexities of network communication. RPC can use either JSON or XML for encoding, leading to two distinct API types: JSON-RPC and XML-RPC.
In conclusion, API protocols play a crucial role in enabling seamless communication between applications, ensuring interoperability, security, and efficiency. Whether using SOAP, REST, or RPC, each protocol offers unique advantages tailored to different use cases. Choosing the right API protocol depends on factors like data complexity, performance needs, and integration requirements. As technology evolves, understanding these protocols helps businesses and developers build scalable, robust, and efficient systems for modern digital interactions.
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