Open In App

REST API Architectural Constraints

Last Updated : 09 Oct, 2024
Summarize
Comments
Improve
Suggest changes
Like Article
Like
Save
Share
Report
News Follow

REST stands for Representational State Transfer and API stands for Application Program Interface. REST is a software architectural style that defines the set of rules to be used for creating web services. Web services that follow the REST architectural style are known as RESTful web services. It allows requesting systems to access and manipulate web resources by using a uniform and predefined set of rules. Interaction in REST-based systems happens through the Internet’s Hypertext Transfer Protocol (HTTP). 

A Restful system consists of a:

  • A client who requests for the resources.
  • server who has the resources.

It is important to create REST API according to industry standards which results in ease of development and increase client adoption. 

Architectural Constraints of RESTful API

There are six architectural constraints that makes any web service are listed below:

  • Uniform Interface
  • Stateless
  • Cacheable
  • Client-Server
  • Layered System
  • Code on Demand

The only optional constraint of REST architecture is code on demand. If a service violates any other constraint, it cannot strictly be referred to as RESTful. 

If you’re interested in mastering API design and development, our JavaScript Course covers the fundamentals of REST APIs and demonstrates how to integrate them into JavaScript applications.

Uniform Interface

It is a key constraint that differentiates between a REST API and a Non-REST API. It suggests that there should be a uniform way of interacting with a given server irrespective of device or type of application (website, mobile app). 

There are four guidelines principles of a Uniform Interface are:

  • Resource-Based: Individual resources are identified in requests. For example: API/users.
  • Manipulation of Resources Through Representations: The client has a representation of the resource and it contains enough information to modify or delete the resource on the server, provided it has permission to do so. Example: Usually user gets a user ID when the user requests a list of users and then uses that ID to delete or modify that particular user.
  • Self-descriptive Messages: Each message includes enough information to describe how to process the message so that the server can easily analyze the request.
  • Hypermedia as the Engine of Application State (HATEOAS): It need to include links for each response so that client can discover other resources easily.

Stateless

It means that the necessary state to handle the request is contained within the request itself and server would not store anything related to the session. In REST, the client must include all information for the server to fulfill the request whether as a part of query params, headers or URI. Statelessness enables greater availability since the server does not have to maintain, update or communicate that session state. There is a drawback when the client need to send too much data to the server so it reduces the scope of network optimization and requires more bandwidth.

Cacheable

Every response should include whether the response is cacheable or not and for how much duration responses can be cached at the client side. Client will return the data from its cache for any subsequent request and there would be no need to send the request again to the server. A well-managed caching partially or completely eliminates some client–server interactions, further improving availability and performance. But sometime there are chances that user may receive stale data. 

Client-Server

REST application should have a client-server architecture. A Client is someone who is requesting resources and are not concerned with data storage, which remains internal to each server, and server is someone who holds the resources and are not concerned with the user interface or user state. They can evolve independently. Client doesn’t need to know anything about business logic and server doesn’t need to know anything about frontend UI. 

Layered system

An application architecture needs to be composed of multiple layers. Each layer doesn’t know any thing about any layer other than that of immediate layer and there can be lot of intermediate servers between client and the end server. Intermediary servers may improve system availability by enabling load-balancing and by providing shared caches. 

Code on demand

It is an optional feature. According to this, servers can also provide executable code to the client. The examples of code on demand may include the compiled components such as Java Servlets and Server-Side Scripts such as JavaScript. 

Rules of REST API

There are certain rules which should be kept in mind while creating REST API endpoints.

  • REST is based on the resource or noun instead of action or verb based. It means that a URI of a REST API should always end with a noun. Example: /api/users is a good example, but /api?type=users is a bad example of creating a REST API.
  • HTTP verbs are used to identify the action. Some of the HTTP verbs are – GET, PUT, POST, DELETE, GET, PATCH.
  • A web application should be organized into resources like users and then uses HTTP verbs like – GET, PUT, POST, DELETE to modify those resources. And as a developer it should be clear that what needs to be done just by looking at the endpoint and HTTP method used.
URI HTTP verb Description
api/users GET Get all users
api/users/new GET Show form for adding new user
api/users POST Add a user
api/users/1 PUT Update a user with id = 1
api/users/1/edit GET Show edit form for user with id = 1
api/users/1 DELETE Delete a user with id = 1
api/users/1 GET Get a user with id = 1
  • Always use plurals in URL to keep an API URI consistent throughout the application.
  • Send a proper HTTP code to indicate a success or error status.

Note: You can easily use GET and POST but in order to use PUT and DELETE you will need to install method override. You can do this by following below code :

npm install method-override --save

This simply require this package in your code by writing :

var methodOverride = require("method-override");

Now you can easily use PUT and DELETE routes :

app.use(methodOverride("_method"));

HTTP verbs

Some of the common HTTP methods/verbs are described below:

  • GET: Retrieves one or more resources identified by the request URI and it can cache the information receive.
  • POST: Create a resource from the submission of a request and response is not cacheable in this case. This method is unsafe if no security is applied to the endpoint as it would allow anyone to create a random resource by submission.
  • PUT: Update an existing resource on the server specified by the request URI.
  • DELETE: Delete an existing resource on the server specified by the request URI. It always return an appropriate HTTP status for every request.
  • GET, PUT, DELETE methods are also known as Idempotent methods. Applying an operation once or applying it multiple times has the same effect. Example: Delete any resource from the server and it succeeds with 200 OK and then try again to delete that resource than it will display an error message 410 GONE.


Similar Reads

Explain the architectural structure of Ember.js applications
Ember.js is a JavaScript framework for building web applications. It uses the Model-View-View Model (MVVM) architectural pattern, which separates the application's data model, user interface, and logic into distinct components. Architectural structure: The architecture of an Ember.js application consists of the following components: Router and Rout
5 min read
Difference Between REST API and RPC API
REST and RPC are design architectures widely used in web development to build APIs (Application Programming Interface). It is a set of instructions that permits two systems to share resources and services. The client creates a request to the server that responds to it with data in JSON or XML format. REST APIs It stands for Representational State T
3 min read
Know the Difference Between REST API and RESTful API
APIs (Application Programming Interface) act as an interface between two applications to interact and provide the relevant data. It uses a set of protocols using which the operation is done. Salesforce was the first organization to officially launch API, followed by eBay and Amazon. Also, 60% of transactions made on eBay use their APIs. If we talk
5 min read
Difference between REST API and SOAP API
REST (Representational State Transfer) and SOAP (Simple Object Access Protocol) are the most common methods for communications These services enable web to communicate with the servers with HTTP protocol. REST is architectural style that works over HTTP for communication while SOAP is a protocol with strict standards and is helpful for complex syst
2 min read
Node.js Building simple REST API in express
Let's have a brief introduction about the Express framework before starting the code section:Express: It is an open-source NodeJs web application framework designed to develop websites, web applications, and APIs in a pretty easier way. Express helps us to handle different HTTP requests at specific routes.As it is NodeJs web framework so make sure
2 min read
How to create a REST API using Java Spring Boot
Representational state transfer (REST) is a software architectural style that defines a set of constraints to be used for creating Web services. Web services that conform to the REST architectural style, called RESTful Web services, provide interoperability between computer systems on the Internet. RESTful Web services allow the requesting systems
6 min read
REST API in Hyperledger
REST, or Representational State Transfer, is an architectural style for building web services. It is based on a set of principles that define how web resources should be defined, accessed, and manipulated. One of the key principles of REST is the use of the HTTP protocol for communication between clients and servers. This means that REST APIs are b
7 min read
How to create Covid19 Country wise status project using REST API ?
Today, All Countries in the world fighting with Coronavirus. Every day, Coronavirus cases rising rapidly. It is important for all to keep track of COVID Cases daily and should try to keep himself/herself safe. We have made small web apps that will tell you the total no of cases, new cases, new death, recovery, etc. to the user. You have to just ent
7 min read
Best Coding Practices For Rest API Design
JSON, Endpoints, Postman, CRUD, Curl, HTTP, Status Code, Request, Response, Authentication, All these words are familiar to you if you are in backend development and you have worked on API (Application Programming Interface). Being a developer you might have worked on some kind of APIs (especially those who are experienced developers). Maybe a paym
10 min read
Why REST API is Important to Learn?
API... Being a developer what comes to your mind first when you listen to this word... JSON, Endpoints, Postman, CRUD, Curl, HTTP, Status Code, Request, Response, Authentication, or something else... If you're familiar with the above word then surely you might have worked on some kinds of APIs (especially those who are experienced developers) in yo
8 min read
Consuming a Rest API with Axios in Vue.js
Many times when building an application for the web that you may want to consume and display data from an API in VueJS using JavaScript fetch API, Vue resource, jquery ajax API, but a very popular and most recommended approach is to use Axios, a promise-based HTTP client. Axios is a great HTTP client library. Similar to JavaScript fetch API, it use
2 min read
Build a Social Media REST API Using Node.js: A Complete Guide
Developers build an API(Application Programming Interface) that allows other systems to interact with their Application’s functionalities and data. In simple words, API is a set of protocols, rules, and tools that allow different software applications to access allowed functionalities, and data and interact with each other.API is a service created
15+ min read
How to generate document with Node.js or Express.js REST API?
Generating documents with Node and Express REST API is an important feature in the application development which is helpful in many use cases. In this article, we will discuss two approaches to generating documents with Node.js or Express.js REST API. Table of Content Document Generation using PdfKit libraryDocument Generation using Puppeteer libra
3 min read
How to Create A REST API With JSON Server ?
Setting up a RESTful API using JSON Server, a lightweight and easy-to-use tool for quickly prototyping and mocking APIs. JSON Server allows you to create a fully functional REST API with CRUD operations (Create, Read, Update, Delete) using a simple JSON file as a data source. Table of Content GET Request Returns a List of all UsersPOST Request to c
4 min read
Build a document generator with Express using REST API
In the digital age, the need for dynamic and automated document generation has become increasingly prevalent. Whether you're creating reports, invoices, or any other type of document, having a reliable system in place can streamline your workflow. In this article, we'll explore how to build a Document Generator using Node and Express, two powerful
2 min read
REST API Introduction
REpresentational State Transfer (REST) is an architectural style that defines a set of constraints to be used for creating web services. REST API is a way of accessing web services in a simple and flexible way without having any processing. REST technology is generally preferred to the more robust Simple Object Access Protocol (SOAP) technology bec
5 min read
HTTP REST API Calls in ElectronJS
ElectronJS is an Open Source Framework used for building Cross-Platform native desktop applications using web technologies such as HTML, CSS, and JavaScript which are capable of running on Windows, macOS, and Linux operating systems. It combines the Chromium engine and NodeJS into a Single Runtime. We already know about the importance of HTTP REST
13 min read
Consuming a REST API ( Github Users ) using Fetch - React Client
In this article, you will learn to develop a React application, which will fetch the data from a REST API using Fetch. We will use GitHub Users API to fetch the user's public information with their username. You can find the API reference and source code links at the end of this article. Prerequisites:NodeJS or NPMReactJSSteps to Create the React A
3 min read
REST API Call to Get Location Details in Vue.js
In this article, we will know the REST API call to get the location details in VueJS, along with understanding its implementation through the examples. VueJS is one of the best frameworks for JavaScript like ReactJS. The VueJS is used to design the user interface layer, it is easy to pick up for any developer. It is compatible with other libraries
7 min read
What is an Idempotent REST API?
Idempotent REST API means that if the same request is made a number of times then it will have the same impact as making the request just once. Lastly, the idempotent characteristic is essential for creating dependable and linear web services when clients might attempt to send the same request multiple times due to network instability. This is due
7 min read
How to create a REST API using json-server npm package ?
This article describes how to use the json-server package as a fully working REST API. What is json-server? json-server is an npm(Node Package Manager) module/package, used for creating a REST API effortlessly. Data is communicated in JSON(JavaScript Object Notation) format between client and server. Installation: Execute the below command in your
4 min read
What is REST API in Node.js ?
REST (Representational State Transfer) is an architectural style for designing networked applications. A RESTful API is an API that adheres to the principles of REST, making it easy to interact with and understand. In this article, we'll explore what REST API is in the context of Node.js, its principles, and how to create one. Table of Content Unde
11 min read
How to Build a REST API with Next.js 13?
Next.js is the most widely used React framework. Next.js 13.2 introduced a new file-based routing mechanism, called App Router, for building React frontend and serverless backend. In this article, we will be building a simple REST API using Next.js Route Handlers Table of Content Next.js Route HandlersNext.js project initializationBuilding REST API
7 min read
Building a REST API with PHP and MySQL
This brief tutorial is a step-by-step guide on how to develop a REST API using PHP and MySQL. REST API will implement HTTP commands (Get, Post, Put, DELETE) and response will be in form of JSON. For development setup, we will be using the XAMPP while for testing of the API, we will use the Postman app. Steps to Build REST API with PHP and MySQLStep
4 min read
REST API using the Express to perform CRUD (Create, Read, Update, Delete)
In this article, we are going to learn how can we build an API and how can we perform crud operations on that. This will be only backend code and you must know JavaScript, NodeJs, Express.js, and JSON before starting out this. This Node.js server code sets up a RESTful API for managing student data. It provides endpoints for performing CRUD (Create
9 min read
GitHub REST API
The GitHub REST API allows developers to interact with GitHub programmatically, enabling you to manage repositories, handle issues, automate workflows, and integrate GitHub with other tools and platforms. Whether you're building an application, automating repetitive tasks, or just curious about how GitHub works behind the scenes, the REST API is a
4 min read
REST API Endpoints For Git Tags
In Git, tags are used to mark specific commits as important, typically signifying a release. Unlike branches, tags are immutable references, making them perfect for marking stable points in your repository’s history, such as version releases. Why Use REST API for Git Tags?Interacting with Git tags via REST APIs allows for easy integration with CI/C
3 min read
REST API Endpoints For GitHub Actions Variables
GitHub Actions is used to automate workflows, build, test, and deploy code. To make workflows more dynamic and secure, GitHub Actions allows you to use variables, which can store data like configuration values, secrets, or other necessary information. GitHub exposes a REST API to manage these variables efficiently, providing developers with full co
5 min read
Getting Started With GitHub REST API
The GitHub REST API is a powerful tool that allows developers to interact with a list of features of GitHub. Whether you're automating tasks, building integrations, or simply managing your GitHub resources more efficiently, the REST API provides a versatile and accessible entry point. In this article, we will walk you through everything you need to
5 min read
CRUD Operation in REST API using PHP
A REST (Representational State Transfer) API allows communication between a client and a server through HTTP requests. PHP, a widely used server-side scripting language, is well-suited for creating REST APIs due to its simplicity and rich ecosystem. This article provides a step-by-step guide on building a REST API in PHP, covering various approache
5 min read
Article Tags :
three90RightbarBannerImg