If you're looking for API Testing Interview Questions for Experienced or Freshers, you are at right place. There are lot of opportunities from many reputed companies in the world. According to research API Testing has a market share of about 16.7%. So, You still have opportunity to move ahead in your career in API Testing Development. Mindmajix offers Advanced API Testing Interview Questions 2018 that helps you in cracking your interview & acquire dream career as API Testing Developer.

Q. What API testing means?

API stands for Application Programming interface details regarding how some software components must act together. In general terms, API testing is a set of procedures and functions allowing the creation of apps accessing data or features of an operating system or application. All in all, testing of such procedures is acknowledged as API testing.

Q. What are the names of tests executed on APIs?

There can be numerous reasons behind executing API testing and there are a number of tests that can be performed on APIs. Some common API test examples are as follows:

Any data structure which demands proper validation can be updated by API
In case some interruption arises during the process or any other event is prompted, you can call to another API
Tests for inputting condition based return values can be performed
With the help of these tests some resources can be easily modified like process killing, update of the database, etc.
The return values can also be tested which can be even null or are with wrong results
Q. What is the procedure to perform API testing and what exactly needs to be checked?

During the API testing process, a request is raised to the API with the known data. This way you can analyse the validation response. Basically, things that must be checked during performing API testing are:

1. Accuracy of data
2. Schema validation
3. HTTP status codes
4. Data type, validations, order and completeness
5. Authorization checks
6. Implementation of response timeout
7. Error codes in case API returns, and
8. Non-functional testing like performance and security testing

Q. What is the test environment of API?

To set up the test environment of API is not a cake walk. It is bit complete and demands the configuration of the database as well as server according to the need of the software. There is no availability of GUI (Graphical User Interface) in this form of testing.

Once the installation process is over, API is verified for the proper functioning. During the whole process API that is invoked by initial environment is being set up with distinct parameters to examine the test results.

Q. What approach should be followed for the API testing?

There are certain factors that determine the API testing approach. Let’s check them below:

1. Defining the accurate input parameters
2. Verifying the calls of the blend of two or more than two value added parameters
3. Defining the basic functionality and scope of the API program
4. Writing suitable API test cases and making use of testing techniques like equivalence class, boundary value, etc. to verify the functionality
5. Testing case execution
6. Testing result comparisons with the results expected
7. Verifying behaviour of API under conditions like the connection with files etc.