Implement Automated API Contract Tests for Backend Endpoints

[Shalini828]

The project currently has no contract / integration tests to verify that backend API endpoints behave correctly together. Adding contract tests will ensure stability across future updates and catch regressions when backend and frontend evolve independently.

Automated API contract tests will:

1. Validate that API request/response schemas remain stable

2. Ensure expected status codes and response formats

3. Be runnable as part of the CI workflow

I would like to work on this issue under OSCG'26.
Kindly assign this to me.
Thanks !

[Vaishnav-Sabari-Girish]

Hey @Shalini828 ,
Thank you for your interest. But I'm not so sure on how having API Status calls will be beneficial to this specific project. Please explain it to me.

[Shalini828]

Hi @Vaishnav-Sabari-Girish, thanks for asking — that’s a valid question.

Since this project provides an interactive API layer on top of arduino-cli, the API effectively becomes a stable interface between:

• the CLI execution/parsing logic, and
• any UI, automation, or scripting layer consuming these endpoints.

API contract tests would be useful here mainly as a safety net for changes around CLI interaction, not as heavy integration tests.

Specifically, they can help by:

1. Ensuring arduino-cli command outputs are consistently mapped to API responses
   If future CLI versions change stdout/stderr formats or exit codes, contract tests can catch unintended changes in response shape or status codes early.

2. Preventing regressions during refactors
   Even small changes in command execution, output parsing, or error handling could silently break consumers. Contract tests lock down expected request/response behavior.

3. Enabling CI validation without hardware dependency
   By mocking CLI responses, we can validate endpoint behavior in CI without requiring connected Arduino boards.

4. Providing clearer guarantees for contributors and users
   This is especially useful as the project grows or new endpoints are added.

The intent would be lightweight schema + status-code validation for a small number of critical endpoints, integrated into CI — not full end-to-end hardware testing.

If this feels too broad, I’m happy to start with just one key endpoint and keep the scope minimal.

Thanks for taking the time to review this!

[Vaishnav-Sabari-Girish]

Hey @Shalini828 ,
I have assigned this issue to you. Before opening a PR please make sure your PR follows the guidelines as given in the file (check REDME.MD).

Thank you.