REST API: What Does It Mean When an Application Has a REST API?

Introduction to REST API

Representational State Transfer Application Programming Interfaces—more commonly known as REST APIs—are primarily used to integrate applications and automate processes. For example, in the case of Desktop as a Service (DaaS), a REST API can be instrumental in automating the process of deploying virtual desktops as soon as a customer completes a purchase, thereby eliminating the need for human interaction from the DaaS provider.

This capability can be quite useful for Internet service vendors (ISVs) and service providers (SPs) who wish to provide virtual applications and desktops through an automated process. Let’s say I’m a service provider offering DaaS but not taking advantage of REST API-powered automation. When a user clicks a link to request an application or desktop, there has to be someone monitoring the system 24/7, or at least a notification system that would let the ISV know as soon as the purchase is complete. REST API automates the actions required, starting from the user clicking “Buy” down to the actual delivery of the service or application.

What is an API?

A software-to-software interface is known as an API (Application Programming Interface). APIs allow programs to communicate with one another in a safe and standardized manner, delivering the data or functionality required without the need for user participation.

What is REST?

REST is a collection of architectural constraints, not protocols or standards. Developers of APIs can use REST in a variety of ways.

When a client request is received, a RESTful API describes the resource’s status to the requester or endpoint. This information, or representation, is delivered by HTTP in various formats, including JSON (Javascript Object Notation), HTML, XLT, Python, PHP, and plain text. JSON is the most extensively used file format because, despite its name, it is language agnostic and can be understood by both humans and machines.

Who Uses REST API?

Because REST APIs are programming interfaces (the operative word being “programming”), they are seamless to the users. The people directly interacting with REST APIs are usually developers or IT staff who know how to implement the code. So, for example, a developer might use a particular solution’s REST API to connect a web application and allow that application to get content from or perform operations integrated with that solution.

From the user’s perspective, a REST API makes things faster and less complex, minimizing the wait time and human interaction needed to access a service.

Using a REST API

The most common usage is in web services. To take advantage of a solution’s REST API for a web service, the user must know what specific HTTP GET, POST, PUT, and other operations are allowed. This is usually specified in the documentation. The documentation will also include information such as which resources can be created, which resource representations can be retrieved, and which resource representations can be updated, among others.

The Guiding Principles of a REST API

There are 6 guiding principles for the REST API architecture:

1. Uniform Interface

Multiple architectural restrictions aid in achieving a consistent interface and directing component behavior.

The four restrictions listed below can help you create a consistent REST interface:

Identification of resources

Each resource participating in the client-server interaction must be uniquely identified by the interface.

Manipulation of resources via representations

In the server response, all resources should have standard representations. These representations should be used by API users to change the status of the server’s resources.

Messages that are self-descriptive

Every resource representation should have enough information to specify how to handle the message. It should also describe the further activities which the client can take with the resource.

Hypermedia as an application state engine

The client should only have the application’s starting URI. The client program must dynamically control all other resources and interactions using hyperlinks.

2. Client Server

The client-server design pattern enforces the separation of concerns, which allows client and server components to grow separately.

We increase the mobility of the interface across many systems and enhance scaling by streamlining the server components by isolating the user interface issues (clients) from the data storage constraints (server).

Ensure that the interface/contract between both the client and the server does not collapse as the client and the server change.

3. Stateless

The client-server design pattern enforces separation of responsibilities by allowing client and server components to develop independently.

By simplifying the server components and separating the user interface difficulties (clients) from the data storage limits, we increase the mobility of the interface across numerous systems and improve scaling (server).

Guarantee that as the client and server evolve, the interface/contract between them does not collapse.

4. Cacheable

The cacheable requirement mandates that a response mark itself to be cacheable or non-cacheable, either implicitly or explicitly.

If the response is cacheable, the client app is given permission to reuse the response data for similar queries in the future for a certain amount of time.

5. Layered System

By restricting component behavior, the layered systems feature enables an architecture to be formed of hierarchical layers.

For example, each component can only see the layer with which it is interacting in a layered system.

6. Code on Demand – Optional

REST allows clients to extend their capabilities by downloading and running code as applets or scripts.

Clients benefit from the downloaded code since it reduces the number of features that must be pre-implemented. Servers can transmit portions of features to clients in terms of code, which the client just needs to execute.

What a Parallels RAS REST API Means for Customers

In the case of Parallels® Remote Application Server (RAS), REST API enables organizations to integrate their web applications, dashboards, backups, and more. . This capability enables those same organizations to perform cloud automation on several processes and offer new services.

If you want to give the Parallels RAS REST API a test run, try the free, 30-day trial of Parallels RAS now.

Download the Trial