Introduction – Why ReadyAPI Testing Is Important in Interviews
As enterprises move toward API-first and service-oriented architectures, testing APIs thoroughly is critical. Tools like ReadyAPI (by SmartBear) are widely used in enterprise environments—especially for SOAP, REST, security, and data-driven testing.
That’s why ready api testing interview questions are common in:
- QA/API tester interviews
- Automation/SDET roles
- Client and enterprise project discussions
Interviewers want to assess whether you can:
- Design and execute API tests using ReadyAPI
- Validate business logic, not just status codes
- Work with REST and SOAP services
- Handle real-time API failures and edge cases
- Explain test design, data-driven testing, and basic automation
This article is a complete interview guide for ReadyAPI testing, covering clear explanations, real-time examples, JSON/XML samples, status codes, and scenario-based questions—useful for freshers to experienced candidates.
What Is API Testing? (Clear & Simple)
API testing validates Application Programming Interfaces to ensure they:
- Accept valid requests
- Enforce business rules
- Return correct responses and status codes
- Handle invalid inputs and failures gracefully
Simple Example
For a Create Order API:
- Valid payload → 201 Created + orderId
- Invalid quantity → 400 Bad Request
- Missing auth → 401 Unauthorized
API testing focuses on backend logic and data, not UI behavior.
REST vs SOAP vs GraphQL (Interview Comparison)
| Feature | REST | SOAP | GraphQL |
| Protocol | HTTP | XML-based | HTTP |
| Data Format | JSON / XML | XML only | JSON |
| Contract | OpenAPI | WSDL | Schema |
| Performance | Fast | Slower | Optimized |
| Usage in ReadyAPI | Very High | Very High | Limited |
👉 ReadyAPI is especially popular for SOAP + REST enterprise testing, so expect questions on both.
Ready API Testing Interview Questions & Answers (90+)
Section 1: ReadyAPI & API Basics (Q1–Q20)
1. What is ReadyAPI?
A comprehensive API testing tool by SmartBear for REST, SOAP, security, performance, and data-driven testing.
2. How is ReadyAPI different from SoapUI?
ReadyAPI is the commercial version with advanced features like data-driven testing, security scans, and dashboards.
3. What types of APIs can be tested using ReadyAPI?
REST, SOAP, and GraphQL (limited support).
4. What is API testing?
Validating API requests, responses, headers, status codes, and business rules.
5. Why is API testing important?
APIs power multiple applications; a defect can impact many systems.
6. What HTTP methods do you test?
GET, POST, PUT, PATCH, DELETE.
7. What is an endpoint?
A URL representing an API resource, e.g., /accounts/123.
8. What is request payload?
Data sent to the API in the request body.
9. What is response body?
Data returned by the API.
10. What is statelessness?
Each request is independent.
11. What is idempotency?
Same request repeated gives the same result.
12. What is authentication?
Verifying identity (Basic Auth, OAuth, token).
13. What is authorization?
Verifying permissions.
14. What authentication methods does ReadyAPI support?
Basic Auth, OAuth 1.0/2.0, API keys, certificates.
15. What is WSDL?
Web Services Description Language for SOAP APIs.
16. What is schema validation?
Validating response structure against contract.
17. What is API chaining?
Using one API’s response in another request.
18. What is negative API testing?
Testing invalid inputs and error handling.
19. What is API versioning?
Managing changes via /v1, /v2.
20. What is data-driven testing?
Running tests with multiple datasets.
HTTP Status Codes – Must Know for ReadyAPI Interviews
| Code | Meaning | When Used |
| 200 | OK | Successful GET |
| 201 | Created | Resource created |
| 204 | No Content | Successful DELETE |
| 400 | Bad Request | Invalid input |
| 401 | Unauthorized | Invalid auth |
| 403 | Forbidden | Access denied |
| 404 | Not Found | Wrong endpoint |
| 409 | Conflict | Duplicate record |
| 422 | Unprocessable | Business rule failure |
| 500 | Server Error | Backend crash |
Section 2: ReadyAPI Features & Validations (Q21–Q45)
21. What validations do you perform in ReadyAPI?
Status code, response body, headers, schema, response time.
22. Is status code validation enough?
No—business rules and data must be validated.
23. How do you validate JSON responses in ReadyAPI?
Using assertions like JSONPath Match.
24. How do you validate XML responses?
Using XPath and schema assertions.
25. What is a TestSuite in ReadyAPI?
A collection of related test cases.
26. What is a TestCase?
A sequence of test steps.
27. What is a TestStep?
An individual request or action.
28. What assertion types are available?
Status Code, Contains, JSONPath, XPath, Schema, SLA.
29. What is SLA assertion?
Validates response time limits.
30. What is Property Transfer?
Passing values between requests.
31. What is Environment in ReadyAPI?
Configuration for different environments.
32. What is data source?
External data (Excel, DB, CSV).
33. What is data loop?
Iterates tests over datasets.
34. What is Groovy scripting?
Scripting language used for custom logic.
35. What is API mocking?
Simulating API responses.
36. What is security testing in ReadyAPI?
Scanning for vulnerabilities (SQLi, auth issues).
37. What is load testing?
Validating performance under load.
38. What is regression testing?
Re-testing after changes.
39. What is smoke testing?
Basic health checks.
40. What is content-type validation?
Ensuring JSON/XML format.
41. What is header validation?
Validating headers like Authorization.
42. What is pagination testing?
Validating paged responses.
43. What is filtering testing?
Validating query parameters.
44. What is sorting testing?
Validating response order.
45. What is API rollback testing?
Ensuring no partial data on failure.
Real-Time API Validation Example (ReadyAPI)
Sample Request
POST /api/orders
Content-Type: application/json
Authorization: Bearer <token>
{
“productId”: 501,
“quantity”: 2
}
Sample Response
{
“orderId”: 9001,
“status”: “CREATED”,
“total”: 120.50
}
Validations
- Status code = 201
- orderId exists
- quantity > 0
- total is numeric
ReadyAPI Assertions & Automation Snippets
JSONPath Assertion (Concept)
- Validate: $.status == “CREATED”
Groovy Script (Example)
def response = context.response
assert response.contains(“CREATED”)
Bonus: Automation Snippets (Interview Advantage)
Rest Assured (Java)
given()
.contentType(“application/json”)
.body(payload)
.when()
.post(“/orders”)
.then()
.statusCode(201);
Python Requests
import requests
res = requests.post(url, json=payload, headers=headers)
assert res.status_code == 201
Scenario-Based Ready API Testing Interview Questions (15)
- API returns 200 but wrong data—what assertions do you add?
- SOAP service returns fault—how do you debug?
- Token expired but API still works—what defect?
- API works in ReadyAPI but fails in app—why?
- Duplicate records created—what validation missed?
- API slow only under load—what test?
- Partial data saved after failure—what testing needed?
- XML response missing mandatory tag—how catch?
- API schema changes—what breaks?
- Unauthorized user accesses API—what test?
- Pagination returns duplicates—cause?
- Mocked API behaves differently—why?
- Security scan finds SQL injection—next step?
- API returns null fields—how validate?
- CI pipeline fails ReadyAPI tests—what check?
How Interviewers Evaluate Your Answers
Interviewers look for:
- Clear API fundamentals
- Hands-on ReadyAPI usage
- Validation beyond status codes
- Real project scenarios
- Logical debugging and communication
👉 Explain what you test and why.
Ready API Testing Interview Cheatsheet
- Validate status + data + rules
- Use assertions wisely
- Know SOAP + REST
- Practice property transfer
- Understand data-driven testing
- Be ready with real examples
FAQs – Ready API Testing Interview Questions
Q1. Is ReadyAPI only for SOAP?
No, it supports REST, SOAP, security, and performance testing.
Q2. Do interviewers expect Groovy scripting?
Basic understanding is a plus.
Q3. Is ReadyAPI better than Postman?
For enterprise SOAP and advanced testing—yes.
Q4. Biggest mistake candidates make?
Only checking status codes.
Q5. How to prepare quickly?
Practice REST + SOAP services with assertions.