1 Commits

Author	SHA1	Message	Date
brent.edwards	8a87262f86	feat(sandbox): implement overlay filesystem sandbox strategy (#994) ... ## Summary Implement the overlay filesystem sandbox strategy with OverlayFS support and userspace fallback. ### Implementation **`OverlaySandbox`** (`infrastructure/sandbox/overlay.py`, 497 lines): - Detects OverlayFS availability at runtime via `/proc/filesystems` + `os.geteuid() == 0` check - **Real OverlayFS mode** (requires root): creates upper/work/merged dirs, mounts overlay filesystem, captures writes in upper layer - **Userspace fallback** (default in CI/containers): `shutil.copytree` the original into merged dir, tracks changes via `filecmp` diff on commit - `create()`: sets up directory structure, mounts if available - `commit()`: copies changed/added files from overlay to original, removes deleted files - `rollback()`: unmounts (or removes) merged, recreates from scratch - `cleanup()`: unmounts, removes all temp dirs, idempotent ### Domain Model Updates - Added `OVERLAY = "overlay"` to `SandboxStrategy` enum in both `resource_type.py` and `resource.py` - Added `STRATEGY_OVERLAY` to `SandboxFactory`, registered for `fs-mount`, `fs-directory`, `fs-file` resources ### Tests - **22 Behave scenarios**: full lifecycle (create/commit/rollback/cleanup), status transitions, path traversal guard, fallback detection, error handling - **6 Robot integration tests**: end-to-end overlay sandbox operations ### Quality Gates | Session | Result | |---|---| | `nox -s lint` | PASS | | `nox -s typecheck` | PASS (0 errors) | | `nox -s unit_tests` | PASS (10,917 scenarios) | | `nox -s coverage_report` | 97% (>= 97%) | Closes #880 Reviewed-on: #994 Co-authored-by: Brent Edwards <brent.edwards@cleverthis.com> Co-committed-by: Brent Edwards <brent.edwards@cleverthis.com>	2026-03-21 03:14:40 +00:00