molecule-ai-workspace-runtime/molecule_runtime/platform_auth.py
Hongming Wang 851a6d7bfd feat: initial release of molecule-ai-workspace-runtime 0.1.0
Extracts shared workspace runtime from molecule-monorepo/workspace-template
into a publishable PyPI package.

- molecule_runtime/ package with all shared infrastructure modules
- Adapter discovery via ADAPTER_MODULE env var (standalone repos) + built-in scan
- molecule-runtime console script entry point (main_sync)
- CI workflow to publish on version tags
- Published to PyPI as molecule-ai-workspace-runtime==0.1.0

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-04-16 04:26:06 -07:00

106 lines
3.7 KiB
Python

"""Workspace auth-token store (Phase 30.1).
Single source of truth for this workspace's authentication token. The
token is issued by the platform on the first successful
``POST /registry/register`` call and travels with every subsequent
heartbeat / update-card / (later) secrets-pull / A2A request.
The token is persisted to ``<configs>/.auth_token`` so it survives
restarts — we only expect to receive it once from the platform, since
``/registry/register`` no-ops token issuance for workspaces that already
have one on file.
Storage:
${CONFIGS_DIR}/.auth_token # 0600, one line, no trailing newline
Callers interact with three functions:
:func:`get_token` — returns the cached token or None
:func:`save_token` — persists a freshly-issued token
:func:`auth_headers`— builds the Authorization header dict for httpx
"""
from __future__ import annotations
import logging
import os
from pathlib import Path
logger = logging.getLogger(__name__)
# In-process cache so we don't hit disk on every heartbeat. The heartbeat
# loop fires on a short interval and reading a tiny file 10x per minute
# is wasteful. The file is the durable copy; this var is the hot path.
_cached_token: str | None = None
def _token_file() -> Path:
"""Path to the on-disk token file. Respects CONFIGS_DIR, falls back
to /configs for the default container layout."""
return Path(os.environ.get("CONFIGS_DIR", "/configs")) / ".auth_token"
def get_token() -> str | None:
"""Return the cached token, reading it from disk on first call."""
global _cached_token
if _cached_token is not None:
return _cached_token
path = _token_file()
if not path.exists():
return None
try:
tok = path.read_text().strip()
except OSError as exc:
logger.warning("platform_auth: failed to read %s: %s", path, exc)
return None
if not tok:
return None
_cached_token = tok
return tok
def save_token(token: str) -> None:
"""Persist a newly-issued token. Creates the file with 0600 mode atomically.
Uses ``os.open(O_CREAT, 0o600)`` so the file is never world-readable,
even transiently. The previous ``write_text()`` + ``chmod()`` approach
had a TOCTOU window where a concurrent reader could access the token
between the two syscalls (M4 — flagged in security audit cycle 10).
Idempotent — if an identical token is already on disk we skip the
write so we don't churn the file's mtime or trigger spurious
filesystem watchers."""
global _cached_token
token = token.strip()
if not token:
raise ValueError("platform_auth: refusing to save empty token")
if get_token() == token:
return
path = _token_file()
path.parent.mkdir(parents=True, exist_ok=True)
# O_CREAT | O_WRONLY | O_TRUNC with mode=0o600 atomically creates (or
# truncates) the file with restricted permissions in a single syscall,
# eliminating the TOCTOU window.
fd = os.open(str(path), os.O_WRONLY | os.O_CREAT | os.O_TRUNC, 0o600)
try:
os.write(fd, token.encode())
finally:
os.close(fd)
_cached_token = token
def auth_headers() -> dict[str, str]:
"""Return a header dict to merge into httpx calls. Empty if no token
is available yet — callers send the request as-is and the platform's
heartbeat handler grandfathers pre-token workspaces through until
their next /registry/register issues one."""
tok = get_token()
if not tok:
return {}
return {"Authorization": f"Bearer {tok}"}
def clear_cache() -> None:
"""Reset the in-memory cache. Used by tests that write fresh token
files between cases."""
global _cached_token
_cached_token = None