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The importance of API in modern applications is a known fact nowadays. APIs help to build an application so efficient and secure as well. The Integration with other third-party components became so easier now because of APIs. APIs are developed by following majorly three types of architecture or protocols.

Now, coming back to the main agenda behind this article. As we often see, we may need some dummy or fake APIs to ensure the backend functionalities of the applications, either in its Development phase or in its Testing phase. Sometimes the actual API which supposes…

Image source — google image, edited with Microsoft PowerPoint

Unit Testing with Mocha, Chai, and Sinon — SPY

“Unit testing finds problems early in the development cycle. This includes both bugs in the programmer’s implementation and flaws or missing parts of the specification for the unit” — Wikipedia

The above statement describes the purpose of good Unit Testing, so we need to ensure that besides the coding we are also writing some proper unit tests which can ensure the functionality coverage and as well as help to find major or critical bugs in the early stage of the software development lifecycle.

In this article, we will understand the process of writing some Unit Tests by implementing the Spy

Image source is google image and edited with MS Power Point


Almost every developer who worked with Node.js should know about Express.js. It is one of the popular node.js based framework which is being used by so many developers now a days in entire world.

Unit Testing is one of the major steps in Software Development cycle, where developers should have the knowledge of writing some good and reliable unit testing scripts to validate the functionalities of each units (i.e. small part of code or single components) of the application or API and gain the confidence. To meet this requirement another popular node.js based unit testing framework is mocha.

Here in…


As we know manual testing is very tedious job, specially when we need to perform an end to end validation of some application. Each and every time we need to be so cautious about the validation point and the navigation flow. Sometime we felt so boring to perform such lengthy process repeatedly and here the Test Automation concept comes to the picture.

Now a days we have so many good, reliable and fast test automation tools which made our life so easy. Selenium, Katalon, Puppeteer, Webdriverio etc. These all are those which are currently being used by so many people…

Krishnendu Halder

Sr. SDET by profession with 6+ years of experience in the Software Testing domain. Passionate about learning.

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