Python sandbox path isolation for agent worktrees

Problem

Two agent jobs share a machine and write into the same tmp/ or venv/, corrupting each other. Imports resolve to the wrong worktree.

Root Cause

Relative paths and a global PYTHONPATH bleed across processes. Temp dirs default to /tmp shared by all users/jobs.

Solution

JOB_ROOT="${MM_WORKSPACE:-$HOME/job}/runs/$(date +%s)-$$"
mkdir -p "$JOB_ROOT"/{src,out,tmp}
export TMPDIR="$JOB_ROOT/tmp"
export PYTHONPATH="$JOB_ROOT/src${PYTHONPATH:+:$PYTHONPATH}"
cd "$JOB_ROOT"
python3 -m venv .venv
source .venv/bin/activate

In code:

from pathlib import Path
ROOT = Path(__file__).resolve().parents[1]
OUT = ROOT / "out"
OUT.mkdir(exist_ok=True)

Verification

python -c "import tempfile,os; print(tempfile.gettempdir()); print(os.environ.get('PYTHONPATH'))"
# tempdir must be under JOB_ROOT

Notes

Prefer one worktree per PR branch.
Clean old runs/ with a size/time GC so disks do not fill.

FilesExpand file tree

python-sandbox-path-isolation.md

Latest commit

History