Files
hermes-agent/hermes_cli/_update_takeover.py
2026-10-10 15:20:13 +02:00

220 lines
11 KiB
Python

"""Absolute-path bootstrap for historical updater takeover; no app imports yet."""
from __future__ import annotations
import json
import os
from pathlib import Path
import re
import subprocess
import sys
import time
_SHA = re.compile(r"[0-9a-f]{40}|[0-9a-f]{64}")
def prepare(request: dict) -> tuple[Path, dict[str, str]]:
"""Provision the new graph before entering its application interpreter."""
root = Path(request["root"])
sys.path.insert(0, str(root))
# The old shim's UI has been frozen since the pull; from here the new
# tree can publish stages (and pop the panel the old shim couldn't).
from hermes_cli.update_stage import ensure_panel, publish_stage
ensure_panel(root)
# An older updater hands off here instead of update_completion._prepare.
from hermes_cli.gitlock import convert_treeless_checkout_first
convert_treeless_checkout_first(root)
publish_stage("Updating Python dependencies (PM)")
from pm import receipt
from pm.client import ensure_tools_for_sync, sync_venv, venv_is_current
from pm.environments import activation_environment, install_state_dir, runtime_facts_path
from hermes_cli._launchers import resolve_store_python
from hermes_cli.venv_sync import (
arm_completion, collect_superseded_generations, publish_launchers, refuse_foreign_owned_venv)
# The historical updater already moved the tree: owe the tail and the fleet restart before the
# first slow step, exactly like a current updater's commit point, so a kill from here on leaves
# both for the next launch / `hermes update` instead of nothing.
refuse_foreign_owned_venv(root)
arm_completion(root)
_arm_fleet_obligation(root)
correlation = request["update_id"]
with receipt.worker_context(correlation):
# A pre-PM installation has no required-tool facts. A current Python
# generation alone does not prove its Node/Git/tool closure is ready.
ensure_tools_for_sync()
from pm.extras import legacy_selection
extras = legacy_selection(root) if not runtime_facts_path(root).is_file() else None
repair_marker = install_state_dir(root) / ".repair-incomplete"
# Repair preserves the old stamp. Changed source inputs instead need
# an ordinary sync, which builds and validates a fresh generation too.
repair = repair_marker.is_file() and venv_is_current(project_root=root)
# An update never fails because of a plugin: misfits are disabled and reported.
sync_venv(None if repair else extras, explicit=True, project_root=root, repair=repair,
evict_incompatible_plugins=not repair)
collect_superseded_generations(root)
request["pm_receipt"] = receipt.last_for_update(correlation)
publish_launchers(root)
repair_marker.unlink(missing_ok=True)
for name in (".update-incomplete", ".lazy-refresh-incomplete"):
(root / name).unlink(missing_ok=True)
python = resolve_store_python(root)
if python is None:
raise RuntimeError("updated installation has no managed interpreter")
return python, activation_environment(root)
def _arm_fleet_obligation(root: Path) -> None:
"""Owe the fleet restart for the moved tree. Never raises: the update is already committed, and
``main`` would report any exception here as a failed update."""
# This runs in the HISTORICAL interpreter, before PM syncs the new dependencies: only stdlib-only
# modules here (``update_cmd_fleet``'s writer imports ``update_cmd`` -> config -> ruamel, which a
# release older than ruamel does not have). Same arm and per-home fallback as the commit point's;
# its False (a debt other profiles cannot see) is already said out loud, and the tree has moved.
from hermes_cli.update_host_obligation import PROFILE_MARKER_NAME, arm_host_obligation
from hermes_constants import get_hermes_home
# A git-less archive root has no SHA: an SHA-less record still owes the restart; its readers hold
# the fleet to the checkout instead of a named pull.
arm_host_obligation(get_hermes_home() / PROFILE_MARKER_NAME, expected_sha=_head_sha(root))
def _head_sha(root: Path) -> str:
"""HEAD of ``root``, or ``''``. Git may be off PATH (only PM's store copy) or broken here, so a
failed ``rev-parse`` falls back to reading the ref files git itself would read."""
from hermes_cli._early_recovery import _git_dir, _git_executable
from hermes_cli.update_lock import _git_common_dir
try:
head = subprocess.run([_git_executable(), "-C", str(root), "rev-parse", "HEAD"], capture_output=True,
text=True, encoding="utf-8", errors="replace", stdin=subprocess.DEVNULL, timeout=60, check=False)
if head.returncode == 0 and _SHA.fullmatch(head.stdout.strip()):
return head.stdout.strip()
except (OSError, subprocess.SubprocessError):
pass # no runnable git: the ref files below are the whole of the evidence
try:
git_dir = _git_dir(root) # a linked worktree's own dir holds HEAD; its branch refs, the common dir
common = _git_common_dir(root) or git_dir
head = (git_dir / "HEAD").read_text(encoding="utf-8-sig").strip()
if head.startswith("ref:"):
ref = head.removeprefix("ref:").strip()
loose = common / ref
if loose.is_file():
head = loose.read_text(encoding="utf-8-sig").strip()
else:
packed = (common / "packed-refs").read_text(encoding="utf-8-sig").splitlines()
head = next((line.split(" ", 1)[0] for line in packed if line.endswith(f" {ref}")), "")
except (OSError, UnicodeDecodeError):
return ""
return head if _SHA.fullmatch(head) else ""
def _record_failure(request: dict, result: Path, code: int, detail: str) -> None:
from hermes_cli import update_receipt
from hermes_constants import get_hermes_home
update_receipt.record_step("historical_takeover", False, detail)
saved = update_receipt.finalize_pending_update_receipt(code, detail)
if request.get("gateway_mode"):
(get_hermes_home() / ".update_exit_code").write_text(f"{code}\n", encoding="utf-8")
result.write_text(json.dumps({"receipt_handled": saved is not None, "resume_handled": False}), encoding="utf-8")
def main() -> int:
context, result = map(Path, sys.argv[1:3])
request = json.loads(context.read_text(encoding="utf-8-sig"))
sys.path.insert(0, request["root"])
if "stopped_serves" in request:
# Historical atexit cleanup may run after the update's result is fixed.
# It must reuse that installation, never start a second update/repair.
from hermes_cli._launchers import resolve_store_python
from pm.environments import activation_environment
root = Path(request["root"])
python = resolve_store_python(root)
if python is None:
print("Cannot resume stopped backends: no selected Hermes interpreter", file=sys.stderr)
return 1
return subprocess.run(
[str(python), "-I", "-B", "-X", "utf8", str(root / "hermes_cli/update_serve_resume.py"),
str(context), str(result)], cwd=root, env=activation_environment(root),
check=False,
).returncode
from hermes_cli import update_receipt
from hermes_cli.update_lock import UpdateLock, describe_holder
# The takeover syncs dependencies and its update_finish child builds the checkout: hold
# (or join, inherited from the old updater) the checkout lock, not just the marker (R2).
lock = UpdateLock(install_root=Path(request["root"]))
if not lock.acquire():
print(describe_holder(lock.holder), file=sys.stderr)
return 2
old_receipt = request.get("receipt") or {}
update_receipt.begin_update_receipt(previous=old_receipt, correlation_id=old_receipt.get("update_id"))
request["update_id"] = update_receipt.current_correlation_id()
try:
try:
python, env = prepare(request)
request["receipt"] = update_receipt._current.get().data
context.write_text(json.dumps(request), encoding="utf-8")
except Exception as exc: # health: allow BLE001 -- pre-commit boundary: any preparation failure is the takeover's recorded failure
print(f"Update preparation failed: {exc}", file=sys.stderr, flush=True)
_record_failure(request, result, 1, f"historical takeover preparation failed: {exc}")
return 1
try:
return _run_finish_child(request, context, result, python, env)
except Exception as exc: # health: allow BLE001 -- post-commit boundary: the tree moved and the tail is armed
_record_owed_finish(request, result, f"the update finish child could not run ({exc})")
return 0
finally:
lock.release()
def _run_finish_child(request: dict, context: Path, result: Path, python: Path, env: dict) -> int:
# This file is new too. Direct execution bypasses normal launch-time
# update liveness checks while the waiting parent still holds its lock.
command = [str(python), "-I", "-B", "-X", "utf8", str(Path(request["root"]) / "hermes_cli/update_finish.py"),
str(context), str(result)]
from hermes_cli.update_custody import popen_post_commit
# update_finish builds the checkout: POSIX lock fd; Windows bound to the job (or leased).
with popen_post_commit(command, label="update finish child", cwd=request["root"], env=env) as child:
try:
code = child.wait()
except BaseException:
child.kill()
raise
if code != 0 and not result.is_file():
_record_failure(request, result, code, f"completion child exited {code} without acknowledgement")
return code
def _record_owed_finish(request: dict, result: Path, detail: str) -> None:
"""The historical updater already moved the tree and ``prepare`` armed the completion tail, so a
finish child that could not be started or resumed is an owed follow-up, never a failed update:
the next launch runs the tail. Receipt finalized with exit 0. Never raises."""
from contextlib import suppress
print(f" ⚠ The update is installed, but its finishing steps did not run: {detail}. "
"The next `hermes` launch finishes them.", file=sys.stderr, flush=True)
saved = None
# Receipt/exit-code writes are best effort: a committed update exits 0 whatever they hit.
with suppress(Exception): # health: allow BLE001 -- post-commit boundary: a receipt error never fails the update
from hermes_cli import update_receipt
update_receipt.record_step("historical_takeover", False, f"owed: {detail}")
saved = update_receipt.finalize_pending_update_receipt(0, f"committed; finishing steps owed: {detail}")
if request.get("gateway_mode"):
with suppress(Exception): # health: allow BLE001 -- post-commit boundary: see above
from hermes_constants import get_hermes_home
(get_hermes_home() / ".update_exit_code").write_text("0\n", encoding="utf-8")
with suppress(OSError): # no result file: the old updater keeps its own receipt and resumes
result.write_text(json.dumps({"receipt_handled": saved is not None, "resume_handled": False}),
encoding="utf-8")
if __name__ == "__main__":
raise SystemExit(main())