600+ API Testing Interview Questions Practice Test

API Testing Interview Questions and Solutions Preparation Observe Take a look at | Freshers to Skilled | [Updated 2024]

Welcome to “API Testing Interview Questions Observe Take a look at” the last word preparation course designed for aspiring software program testers, QA engineers, and builders seeking to deepen their understanding of API testing and ace job interviews on this area. With a meticulously structured curriculum spanning six complete sections and detailed subtopics, this course affords in depth observe checks and interview questions designed to equip you with the information, abilities, and confidence wanted to reach the aggressive area of API testing.

Construction:

1. API Testing Fundamentals
   • Understanding of API Testing: Dive into the necessities of API testing, studying what APIs are and why testing them is essential.
   • Varieties of APIs: Discover the various kinds of APIs, together with REST, SOAP, and GraphQL, and perceive their distinctive testing necessities.
   • HTTP Strategies and Standing Codes: Become familiar with the spine of net communication and the way these strategies and codes are pivotal in API testing.
   • API Testing vs. Unit Testing: Perceive the variations and when to use every testing methodology.
   • Instruments for API Testing: Familiarize your self with the instruments that make API testing environment friendly, similar to Postman and SoapUI.
   • Significance of API Documentation in Testing: Study why correct documentation is essential to profitable API testing.
2. Testing Methods and Methods
   • From optimistic and unfavourable testing eventualities to efficiency and safety testing, this part covers the methods and strategies important for thorough API testing.
3. API Testing Automation
   • Automation is a game-changer in API testing. This part delves into instruments, scripting, and challenges in automating API checks, making certain you’re ready for business practices.
4. APIs within the Software program Growth Lifecycle
   • Perceive the position of API testing in Agile and DevOps, and find out about model management, collaboration, and monitoring APIs in manufacturing environments.
5. Superior API Testing Ideas
   • This part is devoted to superior subjects similar to microservices, GraphQL, OAuth, and extra, getting ready you for complicated API testing eventualities.
6. Situation-Based mostly Questions
   • Apply your information to real-world conditions, studying to deal with fee limiting, third-party integrations, and efficiency bottlenecks.

Pattern observe check questions:

Query 1: What’s the main function of API testing?

Choices:

A. To confirm the person interface and person expertise of an utility.

B. To make sure that the enterprise logic of an utility is functioning as anticipated.

C. To test the efficiency and cargo capability of an internet utility.

D. To validate the interplay and communication between completely different software program methods.

Right Reply: D. To validate the interplay and communication between completely different software program methods.

Rationalization: API testing focuses on verifying that the appliance programming interfaces (APIs) meet expectations for performance, reliability, efficiency, and safety. Not like UI testing, which assesses the front-end person expertise, API testing is anxious with the back-end logic and the contractual settlement between completely different software program methods. It ensures that APIs reply accurately to a variety of requests, deal with errors gracefully, and ship constant efficiency. Such a testing is important for methods that depend on exterior companies or elements to function accurately, because it helps determine points within the integration and communication layers that might result in knowledge inaccuracies, efficiency bottlenecks, or safety vulnerabilities.

Query 2: Which HTTP standing code signifies {that a} request has been efficiently processed, however the server shouldn’t be returning any content material?

Choices:

A. 200 OK

B. 204 No Content material

C. 301 Moved Completely

D. 404 Not Discovered

Right Reply: B. 204 No Content material

Rationalization: The 204 No Content material standing code is utilized in HTTP responses when the request has been efficiently processed, however the server doesn’t have any content material to ship within the response physique. This standing code is especially helpful in circumstances the place the consumer must know that the request was profitable however doesn’t must obtain any knowledge again, similar to when submitting a type or updating knowledge on the server. It’s completely different from the 200 OK standing, which signifies {that a} request was profitable and the response consists of the requested knowledge. Understanding the nuances of HTTP standing codes is essential for API testing, as they supply speedy suggestions on the end result of an API request and assist testers shortly determine points with the API’s logic or implementation.

Query 3: In API testing, what’s the significance of testing for HTTP technique idempotency?

Choices:

A. To make sure that the API can deal with a excessive quantity of requests.

B. To confirm that repeated requests with the identical parameters return completely different outcomes.

C. To test that repeated requests with the identical parameters haven’t any extra results after the primary.

D. To validate that the API returns the proper standing code for every technique.

Right Reply: C. To test that repeated requests with the identical parameters haven’t any extra results after the primary.

Rationalization: Idempotency within the context of HTTP strategies is a precept making certain that a number of equivalent requests have the identical impact as making a single request. This idea is important in API testing, particularly for strategies like PUT and DELETE, which mustn’t trigger extra modifications or negative effects if known as a number of instances with the identical parameters. For instance, if an API endpoint deletes a useful resource, subsequent DELETE requests mustn’t end in errors or change the system’s state, regardless of the useful resource now not current. Testing for idempotency is vital to make sure the reliability and predictability of an API, significantly in distributed methods the place community unreliability would possibly trigger shoppers to retry requests.

Query 4: Which sort of API testing focuses on the conduct of the appliance beneath check by simulating numerous utilization eventualities?

Choices:

A. Load Testing

B. Practical Testing

C. Safety Testing

D. Integration Testing

Right Reply: B. Practical Testing

Rationalization: Practical testing of an API includes verifying that the API behaves as anticipated beneath numerous eventualities that mimic real-world use. Such a testing assesses whether or not the API meets the desired necessities and accurately executes all of the duties it’s designed for, similar to retrieving knowledge, dealing with requests, and interacting with different elements or companies. Not like load or safety testing, which concentrate on the API’s efficiency beneath stress or its skill to withstand assaults, useful testing is anxious with the correctness of the API’s operations and outcomes. It’s a important facet of API testing, making certain that the API capabilities accurately for all supposed use circumstances and handles inputs, together with edge circumstances, appropriately.

Query 5: Why is contract testing vital in microservices structure?

Choices:

A. It ensures that companies can deal with excessive site visitors masses.

B. It verifies the safety measures of every microservice.

C. It validates the interactions between completely different companies primarily based on predefined contracts.

D. It checks the database schema compatibility amongst companies.

Right Reply: C. It validates the interactions between completely different companies primarily based on predefined contracts.

Rationalization: Contract testing is essential in a microservices structure as a result of it focuses on validating the interactions between numerous microservices in accordance with predefined contracts. These contracts specify the anticipated requests and responses between companies, making certain that modifications in a single service don’t break the combination with others. In a microservices structure, companies are developed, deployed, and scaled independently, which will increase the danger of integration points resulting from modifications in APIs. Contract testing helps mitigate this threat by robotically verifying that any modifications to a service nonetheless adjust to the contracts established with its shoppers. This strategy promotes a extra resilient and dependable system, the place builders could make modifications with confidence, understanding that they won’t inadvertently disrupt the system’s general performance.

Enroll Now to: Achieve a aggressive edge within the job market with complete information and abilities in API testing.