API Testing Mock Interview| Manual| Test Scenario| Test Cases Interview| Testing Techniques

What exactly needs to be verified in API Testing?

Basically, on API Testing, we send a request to the API with the known data and we analyze the response.
1. Data accuracy
2. HTTP status codes
3. Response time
3. Error codes in case API return any errors
4. Authorization checks
5. Non-functional testing such as performance testing, security testing

What are the main challenges faced in API testing?
Some of the challenges we face while doing API testing are as follows
Selecting proper parameters and its combinations
Categorizing the parameters properly
Proper call sequencing is required as this may lead to inadequate coverage in testing
Verifying and validating the output
Due to the absence of GUI, it is quite difficult to provide input values

Name some most commonly used HTTP methods?
Some of the HTTP methods are

GET: It enables you to retrieve data from a server
POST: It enables you to add data to an existing file or resource in a server
PUT: It lets you replace an existing file or resource in a server
DELETE: It lets you delete data from a server
PATCH: It is used to apply partial modifications to a resource
OPTIONS: It is used to describe the communication options for the target resource
HEAD: It asks for a response identical to that of a GET request, but without the response body




What is the difference between top down & bottom up approach in SOAP Web services?
Top down SOAP Web services include creating WSDL document to create a contract between the web service and the client, with a required code as an option. This is also known as Contract-first approach. The top-down approach is difficult to implement because classes must be written to confirm the contract defined in WSDL. One of the benefits of this method is that both client and server code can be written in parallel.

Bottom up SOAP web services require the code to be written first and then WSDL is generated.

Which test cases are written first white boxes or black box?
The simple answer is black-box test cases are written first.

Let’s see why black-box test cases are written first compared to white box test cases.
Prerequisites to start writing black-box test cases are Requirement documents or design documents. These documents will be available before initiating a project.
Prerequisites to start writing white box test cases are the internal architecture of the application. The internal architecture of the application will be available in the later part of the project i.e., designing.

126. What is the workbench concept in Software Testing?
Workbench is a practice of documenting how a specific activity must be performed. It is often referred to as phases, steps, and tasks.

In every workbench there will be five tasks such as Input, Execute, Check, Output, and rework.

What is Error Seeding?
Error seeding is a process of adding known errors intendedly in a program to identify the rate of error detection. It helps in the process of estimating the tester skills of finding bugs and also to know the ability of the application (how well the application is working when it has errors.)

106. What is Error Guessing?
Error guessing is also a method of test case design similar to error seeding. In error guessing, testers design test cases by guessing the possible errors that might occur in the software application. The intention is to catch the errors immediately.

107. What is Showstopper Defect?
A showstopper defect is a defect which won’t allow a user to move further in the application. It’s almost like a crash.

Assume that login button is not working. Even though you have a valid username and valid password, you could not move further because the login button is not functioning.

108. What is HotFix?
A bug that needs to handle as a high priority bug and fix it immediately.

What are status code(2xx ,3xx ,4xx, 5xx) in API.
Risk Based Testing (RBT) is a software testing type which is based on the probability of risk. It involves assessing the risk based on software complexity, criticality of business, frequency of use, possible areas with Defect etc. Risk based testing prioritizes testing of features and functions of the software application which are more impactful and likely to have defects.

Checklist for Risk Based Testing

Important functionalities in the project.
User visible functionality in the project
The functionality having the largest safety impact