What should an API smoke test consist of?

_An API Smoke Test:_

An API smoke test should consist of a series of high-level tests that verify the API's critical functionalities and overall stability. Here are some essential components to include:

1. _Authentication and Authorization_: Test authentication mechanisms, such as API keys, tokens, or credentials, to ensure proper access control.

2. _Endpoint Verification_: Test each API endpoint to ensure it returns the expected response, including:

    - HTTP status codes (200, 404, 500, etc.)

    - Response headers

    - Response body (JSON, XML, etc.)

3. _Request and Response Formats_: Verify that the API accepts and returns data in the expected formats (JSON, XML, etc.).

4. _Data Validation_: Test data validation for each endpoint, including:

    - Input validation

    - Output validation

5. _Error Handling_: Test error handling mechanisms, including:

    - Error codes

    - Error messages

    - Exception handling

6. _Performance and Scalability_: Perform basic performance and scalability tests, such as:

    - Response times

    - Throughput

    - Resource utilization

7. _Security_: Test basic security measures, such as:

    - SSL/TLS encryption

    - Input sanitization

    - Rate limiting

8. _Documentation and Schema Compliance_: Verify that the API documentation and schema (OpenAPI, Swagger, etc.) match the actual API behavior.

_Scope and Depth:_

Keep in mind that a smoke test should be a high-level, quick, and focused test suite. It's not meant to be an exhaustive or detailed test, but rather a sanity check to ensure the API is functioning as expected.

_Example:_

For a simple API with two endpoints, `/users` and `/orders`, a smoke test might include:

1. Test authentication with a valid API key

2. Verify `/users` returns a list of users with expected fields (e.g., `id`, `name`, `email`)

3. Verify `/orders` returns a list of orders with expected fields (e.g., `id`, `user_id`, `total`)

4. Test error handling by sending an invalid request to `/users`

5. Verify response times are within acceptable limits (< 500ms)

Remember to keep your smoke test concise and focused on critical functionalities.

Do you have any further questions about API smoke testing?