How and What to test in API Requests?

 

BreakDown of API Testing CheatSheet Considering Modern APIs

API Testing Framework/
│
├─── Response Validation/
│ ├─── data/
│ │ ├─── **Structure Validation** (JSON, XML format verification)
│ │ ├─── **Schema Compliance** (API specification matching)
│ │ ├─── **Data Type Verification** (field type validation)
│ │ ├─── **Null/Empty Checks** (missing data handling)
│ │ └─── **Numeric Precision** (decimal and scale validation)
│ │
│ └─── status/
│   ├─── **Success Codes** (200, 201, 202 verification)
│   ├─── **Error Codes** (400, 401, 404, 500 testing)
│   ├─── **Edge Cases** (rate limiting, timeouts)
│   └─── **Consistency Checks** (cross-endpoint validation)
│
├─── Request Validation/
│ ├─── headers/
│ │ ├─── **Required Headers** (Authorization, Content-Type)
│ │ ├─── **Custom Headers** (X-Correlation-ID, security headers)
│ │ └─── **Header Formatting** (malformed header testing)
│ │
│ ├─── payload/
│ │ ├─── **Format Validation** (JSON, XML structure)
│ │ ├─── **Field Validation** (required vs optional)
│ │ ├─── **Boundary Testing** (size limits, overflows)
│ │ └─── **Input Sanitization** (injection attack prevention)
│ │
│ └─── details/
│   ├─── **HTTP Methods** (GET, POST, PUT, DELETE)
│   ├─── **Host Configuration** (URL validation, SSL)
│   ├─── **API Versioning** (version compatibility)
│   ├─── **Path Parameters** (endpoint formatting)
│   └─── **Endpoint Behavior** (business logic validation)
│
└─── Additional Considerations/
├─── **Authentication & Authorization** (token validation, RBAC)
├─── **Performance Testing** (response time, load testing)
├─── **Error Handling** (graceful failures, logging)
├─── **Security Testing** (vulnerability scanning)
└─── **Caching** (cache headers, invalidation)

1) Response Validation serves as your quality gateway, ensuring that what comes back from your API meets both technical and business requirements.

2) Request Validation acts as your input security checkpoint, making sure that what goes into your API is properly formatted, authorized, and safe.

➡ What are Response Data, Status Codes & Request Components?
➡ Response Data Testing: Systematic validation of the actual content returned by your API, ensuring structural integrity and business rule compliance.

➡ Status Code Testing: Verification that your API communicates its state correctly through HTTP status codes, helping clients understand what happened with their requests.

➡ Request Component Testing: Comprehensive examination of all parts of incoming requests to ensure they meet security, formatting, and business requirements.

Boost API Performance with these Strategies

 

1. Use Caching

Description: Caching stores frequently accessed data temporarily in memory.
Benefits: Speeds up response times by avoiding repeated database access.
Implementation Tips: Use in-memory solutions like Redis for high-speed data retrieval.

2. Minimize Payload Size

Description: Reduce data in responses to only the essentials.
Benefits: Saves bandwidth and enhances speed, especially in large datasets.
Implementation Tips: Use field filtering, compression, and pagination to control payload size.

3. Asynchronous Processing

Description: Run non-critical processes asynchronously to keep APIs available.
Benefits: Ensures users receive faster responses for essential actions.
Implementation Tips: Use queues or async frameworks for background processing of tasks like logging or notifications.

4. Load Balancing

Description: Distribute incoming API requests among multiple servers.
Benefits: Increases reliability and can handle a larger load.
Implementation Tips: Set up load balancers to dynamically allocate traffic based on server capacity.

5. Optimize Data Formats

Description: Use efficient formats like JSON or Protocol Buffers instead of bulkier options like XML.
Benefits: Smaller formats decrease the time required for data parsing and transmission.
Implementation Tips: Prefer binary formats for internal communication to reduce payload size further.

6. Connection Pooling

Description: Reuse open connections to databases or services rather than reconnecting each time.
Benefits: Reduces latency from establishing connections and speeds up requests.
Implementation Tips: Implement connection pools with configurable limits to handle concurrent requests efficiently.

7. Use Content Delivery Networks (CDNs)

Description: CDNs cache static content closer to the end user.
Benefits: Decreases latency by shortening data travel distances.
Implementation Tips: Use for static assets like images or JavaScript files for APIs needing regular access to such resources.

8. Implement API Gateway

Description: API gateways manage request routing, authentication, rate limiting, and caching.
Benefits: Enhances API scalability and offloads repetitive tasks.
Implementation Tips: Configure API gateways to route requests based on type, manage security, and throttle traffic effectively.

9. Avoid Overfetching and Underfetching

Description: Build endpoints to return exactly what the client needs, neither too much nor too little.
Benefits: Reduces unnecessary data transfer, improving performance and efficiency.
Implementation Tips: Use GraphQL to allow clients to specify precise data needs, addressing common issues in REST APIs.
Using these strategies can significantly improve API responsiveness, enhance user experience, and scale infrastructure effectively.

Happy Learning !! :)