API tests automation – Why it is important

Why API tests automation should be considered over GUI test automation?

* Automating API tests takes less time to develop and helps team to achieve testing in the speed of agile.

* Automated API tests executes faster than GUI tests and helps team to get results quickly.

* Well defined automated API tests are easy to maintain and helps to find defects by doing early evaluation of products.

* Since there is no GUI and browser components involved, they are less brittle.

* API tests can be written to test integrated services/system as well as individual and third party services.

* These tests can be extended to test load and performance testing scenarios.

* API tests automation requires less code, provides faster test results and better test coverage. Overall testing cost is reduced.

However we need GUI tests focusing on testing an application user interface to ensure that its functionality is correct. GUI tests cannot be eliminated as whole but can be reduced in numbers.

What are all prerequisites for API testing:
Knowledge about API and how it works
Knowledge about making API calls using tools, commands or any programming language

Few API testing tools:

• Soap UI
• Postman client for Google Chrome browser
• Restlet client for Google Chrome browser
• REST – assured with Java
• Unirest with java

This list is bigger but I just mentioned few items.

Types of Bugs that API testing detects

• Incorrect handling of valid and invalid argument values
• Incorrect response structure or data
• Reliability issues like connecting to API, response time
• Unused data or flags passed between UI and back end
• Improper errors/warning to caller
• Security issues
• Missing or duplicate functionality
• Redundant functionality or APIs

Test data management for API testing is as important as API testing.

Let’s understand more about API, test data management for APIs and tests in upcoming posts.