Writing Test Cases for APIs - Notes By ShariqSP

Understanding and Writing Test Cases for APIs

Writing test cases for APIs ensures that the application functions as expected, handles edge cases properly, and provides meaningful feedback in error scenarios. Below is an embedded link to a detailed set of API test cases, which you can use as a reference for understanding the structure and content of API testing:

Key Components of an API Test Case

  • Test Case ID: A unique identifier for the test case, such as "TC-GET-/api/users".
  • Test Case Description: A brief explanation of the test, e.g., "Verify GET request to fetch user details".
  • API Endpoint: The URL path being tested, e.g., "/api/users".
  • HTTP Method: The method used for the API call (GET, POST, PUT, DELETE, etc.).
  • Request Parameters: The required inputs for the API, defined in JSON format.
  • Expected Response: A detailed description of the anticipated outcome, including HTTP status codes and response payloads.
  • Actual Response: The observed outcome during execution, used for comparison with the expected response.
  • Status: Indicates whether the test passed or failed based on the comparison.
  • Comments: Any additional notes or observations about the test.

Example Test Case

Consider the API endpoint /api/users/update/{id}, which allows updating user details:

Test Case ID TC-PUT-/api/users/update/{id}
Test Case Description Verify that a PUT request updates user details when provided with a valid user ID and payload.
API Endpoint /api/users/update/{id}
HTTP Method PUT
Request Parameters 
                      [
                        {
                          "name": "id",
                          "in": "path",
                          "required": true,
                          "type": "integer"
                        }
                      ]
Expected Response 
                      {
                        "status": 200,
                        "body": {
                          "message": "Successfully updated user."
                        }
                      }
Actual Response TBD
Status TBD
Comments TBD

Use the above structure for each endpoint, customizing details like parameters, expected responses, and test conditions. Refer to the embedded test case link for comprehensive examples and further insights.

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