Fix environment variable casting for dict and list types

[neubig]

This PR fixes issue #8493 by improving the environment variable casting logic for dict and list types.

The issue was in the utils.py file where the code was not properly handling direct dict or list types when casting environment variables. The fix adds support for both field_type is dict/list and get_origin(field_type) is dict/list cases, and uses json.loads first with a fallback to literal_eval for better compatibility.

Added a test case to verify the fix works correctly with dictionary environment variables.

Closes #8493

@neubig can click here to continue refining the PR

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To run this PR locally, use the following command:

docker run -it --rm   -p 3000:3000   -v /var/run/docker.sock:/var/run/docker.sock   --add-host host.docker.internal:host-gateway   -e SANDBOX_RUNTIME_CONTAINER_IMAGE=docker.all-hands.dev/all-hands-ai/runtime:7fd735d-nikolaik   --name openhands-app-7fd735d   docker.all-hands.dev/all-hands-ai/openhands:7fd735d

[enyst]

Thank you for fixing this! I'm not sure why does the agent assume this would be json, though?

The format is toml, these are attributes set in config.toml, and if the user wants, they can set and access them if set in env, instead.

[neubig]

@OpenHands read @enysts comments and re-examine your assumptions about the data format. If you're assumptions are not correct please view the diff with the original code and revert anything to make the minimal changes possible to allow typing to pass

[openhands-ai]

I'm on it! neubig can track my progress at all-hands.dev

[openhands-ai]

I've addressed the comment on PR #8494 regarding the environment variable casting issue. Here's a summary of what I did:

Changes Made

1. Identified the Issue:

   • The PR had changed the parsing of dict and list types from environment variables to first try json.loads and then fall back to literal_eval.
   • @enyst questioned this approach, noting that the format is TOML for config files, not JSON.

2. Analyzed the Codebase:

   • Examined how complex types were handled in existing tests and documentation.
   • Found that the SandboxConfig documentation mentioned JSON for docker_runtime_kwargs, but existing tests used Python literal syntax.

3. Made Minimal Changes:

   • Reverted the parsing logic to use only literal_eval instead of trying json.loads first.
   • Updated the SandboxConfig documentation to specify "Python dictionary literal string" instead of "JSON string".
   • Kept the fix for supporting both field_type is dict/list and get_origin(field_type) is dict/list cases.

4. Verified Changes:

   • Ran the test to ensure it still passes with the updated code.
   • Ran pre-commit hooks to ensure code quality.

5. Committed and Pushed:

   • Committed the changes with a clear message.
   • Successfully pushed to the fix-env-var-casting-issue-8493 branch.

Conclusion

The changes successfully address @enyst's comment by:

1. Removing the assumption that environment variables would be in JSON format
2. Making minimal changes to the original code while still fixing the issue
3. Ensuring type checking passes
4. Maintaining consistency with the rest of the codebase

The PR now uses the same approach for parsing complex types as the rest of the codebase, while still fixing the original issue of supporting both direct and origin-based type checking for dicts and lists.

[neubig]

Thanks @enyst fixed!

[enyst]

Thank you!