API Testing (English)

api-testing

prompts/api-testing_EN.md

When to Use

• User mentions API testing, api-testing
• Need to execute this testing type or produce deliverables per Standard-version
• Trigger examples: "Generate/design/write API test cases for the following"

Output Format Options

How to Use

1. Open

   prompts/api-testing_EN.md

   , copy everything below the dashed line into the AI chat.
2. Append your specific input.
3. For Excel/CSV/JSON, append the request line from output-formats.md.

Code Examples

1. Postman + Newman REST API Testing

examples/postman-rest-api/

• Postman collection file (10 test cases)
• Environment variable configuration
• Newman automation run script
• Detailed README documentation

cd examples/postman-rest-api
npm install -g newman
./newman-run.sh

• User CRUD operations (Create, Read, Update, Delete)
• Authentication and authorization testing
• Error handling and boundary conditions
• Response time validation
• Data format validation

2. REST Assured (Java)

examples/rest-assured-java/

3. SuperTest (Node.js)

examples/supertest-nodejs/

Best Practices

API Test Design Principles

1. Test Pyramid
   • Unit tests: Test individual API endpoints
   • Integration tests: Test interactions between multiple endpoints
   • End-to-end tests: Test complete business workflows
2. Test Data Management
   • Use environment variables for different environment configurations
   • Use dynamic variables to avoid hardcoding
   • Clean up data after tests
3. Assertion Strategy
   • Verify status codes
   • Verify response structure (Schema Validation)
   • Verify response data
   • Verify response time
4. Error Handling
   • Test various error scenarios (4xx, 5xx)
   • Verify error message format
   • Test boundary conditions

Tool Selection Guide

Troubleshooting

Common Issues

1. Newman Run Failure

newman: command not found

# Install Newman globally
npm install -g newman

# Or use npx (no global installation needed)
npx newman run collection.json

2. Environment Variables Not Working

{{variable}}

• Ensure using

  -e

  parameter to specify environment file
• Check if variable names in environment file are correct
• Verify variables are correctly set in Postman

newman run collection.json -e environment.json

3. Certificate Verification Error

SSL certificate problem

# Temporarily disable SSL verification for dev environment (not recommended for production)
newman run collection.json --insecure

# Or specify CA certificate
newman run collection.json --ssl-client-cert-list cert-list.json

4. Request Timeout

Error: ETIMEDOUT

Error: ESOCKETTIMEDOUT

# Increase timeout (milliseconds)
newman run collection.json --timeout-request 30000

# Add request delay
newman run collection.json --delay-request 500

5. Response Data Format Mismatch

• Use Postman's Schema generation feature
• Check API documentation to confirm data structure
• Use

  pm.response.json()

  to print actual response

// Add debug info in Tests
console.log(pm.response.json());

6. Dynamic Data Dependency Issues

// Save data in first request's Tests
pm.environment.set("userId", pm.response.json().id);

// Use in subsequent requests
// URL: {{baseUrl}}/users/{{userId}}

7. Batch Test Run Failures

• Check data dependencies between tests
• Ensure each test can run independently
• Add appropriate delays:

  --delay-request 200

• Use

  --bail

  to stop on first failure

Reference Files

• prompts/api-testing_EN.md — API testing Standard-version prompt
• output-formats.md — Markdown / Excel / CSV / JSON request instructions
• examples/postman-rest-api/ — Complete Postman + Newman example
• quick-start.md — 5-minute quick start guide