Test scenarios

URL Validation

URL validation is a fundamental part of API testing that ensures requests are routed to the correct resources and handled consistently by the system. It verifies how an API responds to valid, invalid, and unexpected endpoint paths, protocols, and methods. Proper URL validation helps prevent routing errors, security gaps, and inconsistent behavior across environments, making APIs more reliable and easier to consume.

Below are some test scenarios and test cases for URL validations.

Scenario 1. Valid Endpoint – Correct URL Handling

When a request is sent to a valid API endpoint, the system should respond successfully. This is the most basic check, yet it establishes the baseline for all other validations. Testing valid endpoints ensures the API routing is correct and reachable. It also confirms that the environment, base URL, and deployment are set up properly.

Test cases

• Send a request to the correct endpoint URL
• Verify the response status is 200 or 201
• Validate that the response body is not empty
• Confirm headers and content type are correct

Scenario 2. HTTP vs HTTPS Protocol Validation

APIs should clearly define whether they accept HTTP or enforce HTTPS. Loose protocol handling can lead to security risks or inconsistent behavior. A secure API either redirects HTTP traffic or blocks it explicitly. This behavior must be predictable and documented.

Test cases

• Send a request using HTTP instead of HTTPS
• Verify redirect response (301, 302, or 307)
• Validate error response when HTTP is blocked
• Confirm HTTPS requests work as expected

Scenario 3. Non-Existent Endpoint Handling

Requests to incorrect or missing endpoints are common in real systems. Typos, outdated paths, or wrong versions can trigger these cases. A well-designed API responds clearly without exposing internal details. Generic or confusing errors make debugging harder for consumers.

Test cases

• Send a request to a typoed endpoint
• Send a request to a removed endpoint
• Verify 404 Not Found status
• Validate error body structure and message

Scenario 4. Trailing Slash Consistency

Some APIs treat /users and /users/ differently, while others do not. Inconsistent handling can cause unexpected failures across environments. The API should either normalize URLs or enforce one standard. Consistency matters more than which rule is chosen.

Test cases

• Call endpoint with trailing slash
• Call endpoint without trailing slash
• Compare response status and body
• Validate behavior consistency across environments

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Scenario 5. Unsupported HTTP Method Validation

Every endpoint supports specific HTTP methods by design. Using an incorrect method should never produce a successful response. Clear method validation prevents misuse and improves API reliability. It also helps consumers quickly identify incorrect implementations.

Test cases

• Send POST instead of GET
• Send DELETE where not supported
• Verify 405 Method Not Allowed response
• Validate allowed methods in response headers

Scenario 6. Case Sensitivity in Endpoint Paths

APIs may be case-sensitive or case-insensitive based on configuration. Mismatch between environments often causes production-only failures. The API should follow one consistent rule across all deployments. Unexpected case handling leads to hard-to-trace bugs.

Test cases

• Call /Users instead of /users
• Call mixed-case endpoint paths
• Verify consistent response behavior
• Confirm rule is same in all environments