Import AITURK IDE 1.0.0-beta.1 from Hermes 63279301; preserve MIT license

gateway/code_skew.py

@@ -0,0 +1,64 @@
+"""Detect when the gateway is running stale code after a hot ``git pull``.
+
+The gateway is a single long-lived process; its ``sys.modules`` is frozen at
+boot. If the checkout is updated underneath it (a manual ``git pull``, or the
+window before ``hermes update``'s graceful restart fires), a first-time lazy
+import on a new code path can resolve a freshly-pulled consumer module against a
+stale cached dependency -> ImportError (see
+``tests/test_stale_utils_module_import.py`` for the exact failure).
+
+We snapshot the checkout revision at gateway startup and compare on demand, so
+risky callers (e.g. ``/model`` switching) can refuse with a clear "restart the
+gateway" message instead of crashing on a cryptic import error.
+
+If the revision can't be read (non-git install, IO error), the boot snapshot
+stays ``None`` and skew detection no-ops — it never produces a false positive.
+"""
+
+from __future__ import annotations
+
+from pathlib import Path
+
+_PROJECT_ROOT = Path(__file__).resolve().parent.parent
+_boot_fingerprint: str | None = None
+
+
+def _fingerprint() -> str | None:
+    """Current checkout fingerprint, reusing the CLI's git-rev reader.
+
+    ``hermes_cli.main`` is always already imported in a gateway process (it's
+    the entry point), so this import is free and avoids duplicating the
+    worktree-aware ref resolution.
+    """
+    try:
+        from hermes_cli.main import _read_git_revision_fingerprint
+
+        return _read_git_revision_fingerprint(_PROJECT_ROOT)
+    except Exception:
+        return None
+
+
+def record_boot_fingerprint() -> None:
+    """Snapshot the checkout revision at gateway startup (idempotent)."""
+    global _boot_fingerprint
+    if _boot_fingerprint is None:
+        _boot_fingerprint = _fingerprint()
+
+
+def _short(fingerprint: str) -> str:
+    """Render a ``git:<ref>:<sha>`` fingerprint as a compact label."""
+    sha = fingerprint.rsplit(":", 1)[-1]
+    if sha and sha != "unresolved" and len(sha) > 10:
+        return sha[:10]
+    return sha or fingerprint
+
+
+def detect_code_skew() -> tuple[str, str] | None:
+    """Return ``(boot_rev, disk_rev)`` short labels if the checkout drifted
+    since boot, else ``None``."""
+    if _boot_fingerprint is None:
+        return None
+    current = _fingerprint()
+    if current is None or current == _boot_fingerprint:
+        return None
+    return _short(_boot_fingerprint), _short(current)