API Automation using Rest Assured

WHY API?

API TESTING is a software testing type that validates Application Programming Interfaces (APIs). API Testing aims to check the programming interfaces’ functionality, reliability, performance, and security. In API Testing, instead of using standard user inputs (keyboard) and outputs, you use software to send calls to the API, get output, and note down the system’s response. API tests are very different from GUI Tests and won’t concentrate on the look and feel of an application. It mainly concentrates on the business logic layer of the software

API is the Middle man, who sends the request from the client to the server getting a response from the server as a status code.

API testing is a type of software testing that involves testing application programming interfaces. API testing is now considered critical for automating testing because APIs now serve as the primary interface to application logic and because GUI tests are difficult to maintain with the short release cycles and frequent changes commonly used with Agile software development and DevOps.

So, API Testing supports the validation of Functional Testing but does not replace it. API Testing does not cover the complete Functional Testing which covers business scenarios – test cases have to be prepared for the same and executed separately. Single API could be called in several functionalities in the Web Application, validation of Single API indirectly validates several Functional Test Scenarios. Functional Testing focuses more on end-user perspective whereas API Testing validates the intermediate stage. It is more like unit Testing to validate the processing using Input parameters and outputs Parameters. In the API test, data is exchanged using XML or JSON.

Compared with graphical user interface (GUI) testing, application programming interface (API) testing provides several key benefits, each of which can improve the coverage of test cycles, conserve resources, and result in faster, more efficient releases

REST ASSURED and How it works

REST stands for Representational State Transfer. REST Assured is a java library used for testing and validating the Restful Web Services. It supports Behaviour-Driven Development(BDD) syntax like Given, When, and Then notations. It helps us to integrate with testing frameworks like Junit or Testing.

Working of REST ASSURED

Let us understand how the Rest Assured Works

Create an HTTP request with all the details

Send the request over the network

Validate the received Response

HTTP Request

• URL

The Request URL is the unique address used to make a request. URL consists of the Base URL, Resource, Query, or Path Parameters.

• HTTP Method/Verb

The four basic Create, Read, Update and Delete (CRUD) operations are performed using the POST, GET, PUT and DELETE methods in the REST interface

POST: This Verb is used to create a new resource on a server.

GET: This Verb is used to get or read data from a server.

PUT or PATCH: Both PUT and PATCH Verbs are used to update a resource on a server. The PUT method is used to update the record entirely. The PATCH method is used to update the record partially instead of updating the entire resource.

DELETE: This Verb is used to delete a resource from a server.

• Headers

Headers represent the meta-data associated with HTTP requests or responses. It is the additional information that is passed between client and server along with the request or response. Headers are used for several purposes, such as authentication, caching, messaging body information, handling cookies, etc. Headers will be key-value pairs or can be a key with multiple values

• Payload/Body

The Payload/Body contains the information that the user wants to send to the server. The payload is used only with the requests that alter the existing resource or create new ones.

• HTTP Response

The HTTP Response consists of the status code, Headers and Response body. As we already discussed Headers and Body we will focus on Status Codes.

Status Codes

HTTPstatus codes help us to understand the status of the response quickly.

100–199: Informational: The request received and process continuing

200–299: Success: The request succeeded

300–399: Redirection: The request is redirecting to another URL

400–499: Client Error: An error occurred from client-side

500–599: Server Error: An error occurred from the server-side

Rest API Response Codes

#1) 100 Series

These are temporary Responses

• 100 Continue
• 101 Switching Protocols
• 102 Processing

#2) 200 Series

The client accepts the Request, being processed successfully at the server.

• 200 – OK
• 201 – Created
• 202 – Accepted
• 203 – Non-Authoritative Information
• 204 – No Content
• 205 – Reset Content
• 206 – Partial Content
• 207 – Multi-Status
• 208 – Already Reported
• 226 – IM Used

3) 300 Series

Most of the codes related to this series are for URL Redirection.

• 300 – Multiple Choices
• 301 – Moved Permanently
• 302 – Found
• 303 – Check Other
• 304 – Not Modified
• 305 – Use Proxy
• 306 – Switch Proxy
• 307 – Temporary Redirect
• 308 – Permanent Redirect

4) 400 Series

These are specific to client-side error.

• 400 – Bad Request
• 401 – Unauthorised
• 402 – Payment Required
• 403 – Forbidden
• 404 – Not Found
• 405 – Method Not Allowed
• 406 – Not Acceptable
• 407 – Proxy Authentication Required
• 408 – Request Timeout
• 409 – Conflict
• 410 – Gone
• 411 – Length Required
• 412 – Precondition Failed
• 413 – Payload Too Large
• 414 – URI Too Long
• 415 – Unsupported Media Type
• 416 – Range Not Satisfiable
• 417 – Expectation Failed
• 418 – I’m a teapot
• 421 – Misdirected Request
• 422 – Unprocessable Entity
• 423 – Locked
• 424 – Failed Dependency
• 426 – Upgrade Required
• 428 – Precondition Required
• 429 – Too Many Requests
• 431 – Request Header Fields Too Large
• 451 – Unavailable For Legal Reasons

#5) 500 Series

These are specific to the server-side error.

• 500 – Internal Server Error
• 501 – Not Implemented
• 502 – Bad Gateway
• 503 – Service Unavailable
• 504 – Gateway Timeout
• 505 – HTTP Version Not Supported
• 506 – Variant Also Negotiates
• 507 – Insufficient Storage
• 508 – Loop Detected
• 510 – Not Extended
• 511 –  Network Authentication Required

FRAMEWORK

Testing frameworks are an essential part of any successful automated testing process. They can reduce maintenance costs and testing efforts and will provide a higher return on investment (ROI) for QA teams looking to optimize for their agile processes.

TYPES OF FRAMEWORK

There are six common types of test automation frameworks, each with its own architecture and different benefits and disadvantages. When building out a test plan, it’s important to choose the framework that is right for you.

Linear Automation Framework

Modular-Based Testing Framework

Library Architecture Testing Framework

Data-Driven Framework

Keyword-Driven Framework

Hybrid Testing Framework

OUR FRAMEWORK

Expedite your Testing – RAFT

RAFT is Re-usable Automation Framework that automates and enhances your testing process by decreasing the cost and man-hours for testing your applications. Our RAFT is a ready-to-use automation framework which enables you to test the Web, Web services, and Mobile applications

API AUTOMATION TOOLS

1. The Katalon Platform

Recognized as the Gartner Peer Insights Customers’ Choices for Software Test Automation for three consecutive years, The Katalon Platform is the leading test automation solution for API, Web, and Mobile and Windows applications.

Feature highlights:

Easy-to-use UI and productivity-centric features for projects of all sizes

Supports REST, SOAP requests, and SSL client certificates

Enable test import from Swagger (2.0 & 3.0), Postman, WSDL, and WADL

Native CI/CD integrations (Jenkins, Azure DevOps, CircleCI, Dockers, etc.)

Data-driven testing methods better test coverage and reliability

Assert support to create fluent assertions in BDD style

Support API test data setup using UI testing

Built-in reporting platform to centralize reports and activities across tool stacks: version control systems, CI/CD, test automation tools, and ALMs

• Postman

Originally a Chrome browser plugin, Postman extended to an on premise solution for both Mac and Windows.

Feature highlights:

Easy-to-use REST client

Offer rich interface

Available for both automated and exploratory testing

Able to run on Mac, Linux, Windows

Provide many integrations like support for Swagger & RAML formats

Run, test, document, and monitor features

• Apigee

Apigee is a cross-cloud API testing tool enabling users to measure and test API performance, support and build API. Apigee also provides PCI, HIPAA, SOC2, and PII for apps. This tool has been named one of the leaders in the 2019 Gartner Magic Quadrant for Full Lifecycle API Management four times in a row.

Feature highlights:

Allows design to monitor, implement and extend API

It is multi-step and powered by Javascript

Define performance issues by tracking API traffic, error rate, and response time

Easily create an API proxy based on open API specifications and deploy it in the cloud

• JMeter

Initially, JMeter was created for performance testing, however, it is commonly used for functional API testing. 

Feature highlights:

Cache and offline replay of test results

Automatically work with CSV files, thus enabling the team to create unique parameter values for the API tests at speed testing

Able to include the API tests in CI pipeline thanks to JMeter and Jenkins integrations

Available for both static and dynamic resources performance

• REST-assured

This open-source Java Domain-specific language enables testing REST services more simply. It can be used to validate and verify the response of these requests.

Feature highlights:

Offer a bunch of baked-in functionalities to help users proceed with the codeless practice

Integrates seamlessly with Serenity automation framework, thus users can combine the UI and REST tests in one framework that extracts excellent reports

Support BDD Given/When/Then syntax

Supports POST, GET, PUT, DELETE, OPTIONS, PATCH and HEAD requests

Users do not need to be an HTTP expert to utilize this tool

• Assertible

Assertible is an API testing tool that focuses on automation and reliability.

Feature highlights:

Support automating API tests throughout CI/CD pipeline

Assist in running API tests after deployments and integrates with familiar tools (e.g., GitHub, Slack, and Zapier)

Support validating HTTP responses with turn-key assertions

Help testers update their tests when their specifications change by The Sync feature. Hence it’s needless to manually update tests after adding new parameters or changing the response of the API

• Soap UI

This headless functional testing tool is dedicated to API testing. It allows users to test REST and SOAP APIs and Web Services with no hassles.

• Karate DSL

This new API testing tool assists users in creating scenarios for API-based BDD tests simply without writing definition steps. Indeed, KarateDSL creates those definitions itself, thus users can quickly kickstart the API testing.

Feature highlights:

Build on top of Cucumber-JVM

Run a test and generate reports likewise to any standard Java project

Supports configuration switching/staging, multithreaded parallel execution

The latest revision, Karate UI 1.3.0, allows for Java 8 and introduces a slew of new features, including redesigned HTML reports, call-Single-Cache, Karate Robot Windows for Windows Desktop app automation, and enhanced tree walking in UI Tests. Also, Karate UI allows you to write tests in any language that can handle HTTP, JSON, or XML.

BENEFITS OF API TESTING

• Test for Core Functionality : one of the key benefits of API Testing is access to the application without a user interface. Testing the core, code-level functionality of the application provides an early evaluation of its overall build strength before running GUI tests. This helps expose the small errors that can fester and become larger problems during GUI testing.
• Language-Independent: In an API Test, data is exchanged using XML or JSON. These transfer modes are completely language-independent, allowing the selection of any core language when pursuing automated testing services for the application.
• Time Effective : API Testing is far less time consuming than functional GUI testing. In GUI testing, webpage elements must be polled, which slows down the testing process immensely. APIs can achieve 80 % of time saving to validate the core functionality of the application.
• Easy Integration with GUI : With API Testing, highly integratable tests are possible. This is especially beneficial if functional GUI testing are executed following API testing.

API TEST AUTOMATION FRAMEWORK

Author: admin   | Posted On: 16th February 2023   | Category: Article