Why API Testing is Important
We live in an exciting age of intelligence, where progress moves at the speed of imagination. We are connected to the world and one another like never before. API(Application Programming Interface) is the hero of our connected world. Here’s everything you need to know to about API’s and how API testing plays a vital role.
What is API ?
An application program interface (API) is a set of routines, protocols, and tools for building software applications. Basically, an API specifies how software components should interact. Additionally, APIs are used when programming graphical user interface (GUI) components.
What is API Testing?
API testing is a type of software testing that involves testing application programming interfaces (APIs) directly and as part of integration testing to determine if they meet expectations for functionality, reliability, performance, and security. Since APIs lack a GUI, API testing is performed at the message layer. During the API testing the data is exchanged from XML or JSON through HTTP requests and responses. These are technology independent and will work with any of the programming languages and technologies.
Why is it Important to Invest in API Testing?
Testing the Application Early without a UI
The later you find defects, the more expensive they are to fix. API testing engages testers early in development lifecycle. With API testing you can start testing your application early even without a UI. This helps to identify and fix issues early in development lifecycle which would otherwise be expensive to fix when identified during GUI testing. The advantage of API testing is that a lot of logic can be validated without being dependent upon the UI.
To Reduce Test Automation Cost and move away from Flaky UI Tests
If we understand the “Automation pyramid” we can come up with an effective automation strategy.
The test pyramid concept was a developed by Mike Cohn and has been described in his book “Succeeding with Agile”. The base of the pyramid are the Unit Tests, these are the tests that are executed against the code.Unit tests are the least expensive to create, they are the fastest to execute and yield highest results. The 2nd layer are the API tests which are executed against the service layer. Finally, at the top of the pyramid are the UI tests that actually validates the application as a whole at presentation layer.
As we move up the pyramid, the cost involved in the creation and maintenance of test, the test execution time, test fragility and test coverage keeps increasing.The automation pyramid preaches that you should do much more automated testing through unit tests and API tests than you should through GUI based testing. Agile’s success is hugely dependent on early feedback.During practices like continuous integration the amount of time the GUI regression tests take to provide feedback when new build is deployed is too long. UI tests are expensive to develop and maintain. A small change in UI can break the tests and lead to a of rework.
Several times the testers are forced to automate at UI layer however the tests end up being unreliable,expensive,slow and flaky.This is one of the reason why many companies fail at efforts to implement an effective automation strategy.
Agile Development and Minimalistic UI and Manual Tests
95% of the organizations practice agile. Agile methodologies are no longer solely the domain of startups and small development shops. The main reasons for adopting agile over the traditional methodologies is to accelerate product delivery and to embrace the changes. Agile has also increased the frequency with which applications are released, which in turn has created an increased demand for new ways to quickly test them. Test automation has become a critical factor to maintain agility. So it is necessary for agile teams increase their level of API testing while decreasing their reliance on GUI testing. API testing is recommended for the vast majority of test automation efforts.
API automation can drastically reduces the pressure of regression testing from the QA team.By integrating the API automated tests to the build server, the QA team can provide a quick feedback on the health of the application as soon as it is deployed. This provides an early evaluation of its overall build strength before running GUI tests.API test automation requires you to code less and provides faster test results and better test coverage. API’s get stabilized early and are unlike to change frequently like the user interface. GUI tests can't sufficiently verify functional paths and back-end APIs/services associated with multi tier architectures. APIs are always the most stable interface to the system under test.
API testing is a unique form of software testing is particularly valuable for the businesses that embrace a continuous integration process. Building API tests during development of any software or service has far-reaching benefits across teams, all the way down to how your customer experiences the product. Making software that your target audience will love is essential to the success of your business and by having your APIs tested rigorously and regularly will ensure a reliable way of achieving it.
