Files
hermes-agent/tools/environments/modal.py

425 lines
15 KiB
Python

"""Modal cloud execution environment using the native Modal SDK directly.
Uses ``Sandbox.create()`` + ``Sandbox.exec()`` instead of the older runtime
wrapper, while preserving Hermes' persistent snapshot behavior across sessions.
"""
import asyncio
import json
import logging
import shlex
import threading
import uuid
from pathlib import Path
from typing import Any, Dict, Optional
from hermes_constants import get_hermes_home
from tools.environments.base import BaseEnvironment
from tools.interrupt import is_interrupted
logger = logging.getLogger(__name__)
_SNAPSHOT_STORE = get_hermes_home() / "modal_snapshots.json"
_DIRECT_SNAPSHOT_NAMESPACE = "direct"
def _load_snapshots() -> Dict[str, str]:
"""Load snapshot ID mapping from disk."""
if _SNAPSHOT_STORE.exists():
try:
return json.loads(_SNAPSHOT_STORE.read_text())
except Exception:
pass
return {}
def _save_snapshots(data: Dict[str, str]) -> None:
"""Persist snapshot ID mapping to disk."""
_SNAPSHOT_STORE.parent.mkdir(parents=True, exist_ok=True)
_SNAPSHOT_STORE.write_text(json.dumps(data, indent=2))
def _direct_snapshot_key(task_id: str) -> str:
return f"{_DIRECT_SNAPSHOT_NAMESPACE}:{task_id}"
def _get_snapshot_restore_candidate(task_id: str) -> tuple[str | None, bool]:
"""Return a snapshot id and whether it came from the legacy key format."""
snapshots = _load_snapshots()
namespaced_key = _direct_snapshot_key(task_id)
snapshot_id = snapshots.get(namespaced_key)
if isinstance(snapshot_id, str) and snapshot_id:
return snapshot_id, False
legacy_snapshot_id = snapshots.get(task_id)
if isinstance(legacy_snapshot_id, str) and legacy_snapshot_id:
return legacy_snapshot_id, True
return None, False
def _store_direct_snapshot(task_id: str, snapshot_id: str) -> None:
"""Persist the direct Modal snapshot id under the direct namespace."""
snapshots = _load_snapshots()
snapshots[_direct_snapshot_key(task_id)] = snapshot_id
snapshots.pop(task_id, None)
_save_snapshots(snapshots)
def _delete_direct_snapshot(task_id: str, snapshot_id: str | None = None) -> None:
"""Remove direct Modal snapshot entries for a task, including legacy keys."""
snapshots = _load_snapshots()
updated = False
for key in (_direct_snapshot_key(task_id), task_id):
value = snapshots.get(key)
if value is None:
continue
if snapshot_id is None or value == snapshot_id:
snapshots.pop(key, None)
updated = True
if updated:
_save_snapshots(snapshots)
def _resolve_modal_image(image_spec: Any) -> Any:
"""Convert registry references or snapshot ids into Modal image objects."""
import modal as _modal
if not isinstance(image_spec, str):
return image_spec
if image_spec.startswith("im-"):
return _modal.Image.from_id(image_spec)
return _modal.Image.from_registry(
image_spec,
setup_dockerfile_commands=[
"RUN rm -rf /usr/local/lib/python*/site-packages/pip* 2>/dev/null; "
"python -m ensurepip --upgrade --default-pip 2>/dev/null || true",
],
)
class _AsyncWorker:
"""Background thread with its own event loop for async-safe Modal calls."""
def __init__(self):
self._loop: Optional[asyncio.AbstractEventLoop] = None
self._thread: Optional[threading.Thread] = None
self._started = threading.Event()
def start(self):
self._thread = threading.Thread(target=self._run_loop, daemon=True)
self._thread.start()
self._started.wait(timeout=30)
def _run_loop(self):
self._loop = asyncio.new_event_loop()
asyncio.set_event_loop(self._loop)
self._started.set()
self._loop.run_forever()
def run_coroutine(self, coro, timeout=600):
if self._loop is None or self._loop.is_closed():
raise RuntimeError("AsyncWorker loop is not running")
future = asyncio.run_coroutine_threadsafe(coro, self._loop)
return future.result(timeout=timeout)
def stop(self):
if self._loop and self._loop.is_running():
self._loop.call_soon_threadsafe(self._loop.stop)
if self._thread:
self._thread.join(timeout=10)
class ModalEnvironment(BaseEnvironment):
"""Modal cloud execution via native Modal sandboxes."""
def __init__(
self,
image: str,
cwd: str = "/root",
timeout: int = 60,
modal_sandbox_kwargs: Optional[Dict[str, Any]] = None,
persistent_filesystem: bool = True,
task_id: str = "default",
):
super().__init__(cwd=cwd, timeout=timeout)
self._persistent = persistent_filesystem
self._task_id = task_id
self._base_image = image
self._sandbox = None
self._app = None
self._worker = _AsyncWorker()
self._synced_creds: Dict[str, tuple] = {}
sandbox_kwargs = dict(modal_sandbox_kwargs or {})
restored_snapshot_id = None
restored_from_legacy_key = False
if self._persistent:
restored_snapshot_id, restored_from_legacy_key = _get_snapshot_restore_candidate(
self._task_id
)
if restored_snapshot_id:
logger.info("Modal: restoring from snapshot %s", restored_snapshot_id[:20])
import modal as _modal
cred_mounts = []
try:
from tools.credential_files import get_credential_file_mounts
for mount_entry in get_credential_file_mounts():
cred_mounts.append(
_modal.Mount.from_local_file(
mount_entry["host_path"],
remote_path=mount_entry["container_path"],
)
)
logger.info(
"Modal: mounting credential %s -> %s",
mount_entry["host_path"],
mount_entry["container_path"],
)
except Exception as e:
logger.debug("Modal: could not load credential file mounts: %s", e)
self._worker.start()
async def _create_sandbox(image_spec: Any):
app = await _modal.App.lookup.aio("hermes-agent", create_if_missing=True)
create_kwargs = dict(sandbox_kwargs)
if cred_mounts:
existing_mounts = list(create_kwargs.pop("mounts", []))
existing_mounts.extend(cred_mounts)
create_kwargs["mounts"] = existing_mounts
sandbox = await _modal.Sandbox.create.aio(
"sleep",
"infinity",
image=image_spec,
app=app,
timeout=int(create_kwargs.pop("timeout", 3600)),
**create_kwargs,
)
return app, sandbox
try:
target_image_spec = restored_snapshot_id or image
try:
# _resolve_modal_image keeps the Modal bootstrap fix together:
# it applies ensurepip via setup_dockerfile_commands before
# Modal builds or restores the image.
effective_image = _resolve_modal_image(target_image_spec)
self._app, self._sandbox = self._worker.run_coroutine(
_create_sandbox(effective_image),
timeout=300,
)
except Exception as exc:
if not restored_snapshot_id:
raise
logger.warning(
"Modal: failed to restore snapshot %s, retrying with base image: %s",
restored_snapshot_id[:20],
exc,
)
_delete_direct_snapshot(self._task_id, restored_snapshot_id)
base_image = _resolve_modal_image(image)
self._app, self._sandbox = self._worker.run_coroutine(
_create_sandbox(base_image),
timeout=300,
)
else:
if restored_snapshot_id and restored_from_legacy_key:
_store_direct_snapshot(self._task_id, restored_snapshot_id)
logger.info(
"Modal: migrated legacy snapshot entry for task %s",
self._task_id,
)
except Exception:
self._worker.stop()
raise
logger.info("Modal: sandbox created (task=%s)", self._task_id)
def _sync_credential_files(self) -> None:
"""Push credential files into the running sandbox."""
try:
from tools.credential_files import get_credential_file_mounts
mounts = get_credential_file_mounts()
if not mounts:
return
for entry in mounts:
host_path = entry["host_path"]
container_path = entry["container_path"]
hp = Path(host_path)
try:
stat = hp.stat()
file_key = (stat.st_mtime, stat.st_size)
except OSError:
continue
if self._synced_creds.get(container_path) == file_key:
continue
try:
content = hp.read_text(encoding="utf-8")
except Exception:
continue
import base64
b64 = base64.b64encode(content.encode("utf-8")).decode("ascii")
container_dir = str(Path(container_path).parent)
cmd = (
f"mkdir -p {shlex.quote(container_dir)} && "
f"echo {shlex.quote(b64)} | base64 -d > {shlex.quote(container_path)}"
)
async def _write():
proc = await self._sandbox.exec.aio("bash", "-c", cmd)
await proc.wait.aio()
self._worker.run_coroutine(_write(), timeout=15)
self._synced_creds[container_path] = file_key
logger.debug(
"Modal: synced credential %s -> %s",
host_path,
container_path,
)
except Exception as e:
logger.debug("Modal: credential file sync failed: %s", e)
def execute(
self,
command: str,
cwd: str = "",
*,
timeout: int | None = None,
stdin_data: str | None = None,
) -> dict:
self._sync_credential_files()
if stdin_data is not None:
marker = f"HERMES_EOF_{uuid.uuid4().hex[:8]}"
while marker in stdin_data:
marker = f"HERMES_EOF_{uuid.uuid4().hex[:8]}"
command = f"{command} << '{marker}'\n{stdin_data}\n{marker}"
exec_command, sudo_stdin = self._prepare_command(command)
# Modal sandboxes execute commands via exec() and cannot pipe
# subprocess stdin directly. When a sudo password is present,
# use a shell-level pipe from printf.
if sudo_stdin is not None:
exec_command = (
f"printf '%s\\n' {shlex.quote(sudo_stdin.rstrip())} | {exec_command}"
)
effective_cwd = cwd or self.cwd
effective_timeout = timeout or self.timeout
full_command = f"cd {shlex.quote(effective_cwd)} && {exec_command}"
result_holder = {"value": None, "error": None}
def _run():
try:
async def _do_execute():
process = await self._sandbox.exec.aio(
"bash",
"-c",
full_command,
timeout=effective_timeout,
)
stdout = await process.stdout.read.aio()
stderr = await process.stderr.read.aio()
exit_code = await process.wait.aio()
if isinstance(stdout, bytes):
stdout = stdout.decode("utf-8", errors="replace")
if isinstance(stderr, bytes):
stderr = stderr.decode("utf-8", errors="replace")
output = stdout
if stderr:
output = f"{stdout}\n{stderr}" if stdout else stderr
return output, exit_code
output, exit_code = self._worker.run_coroutine(
_do_execute(),
timeout=effective_timeout + 30,
)
result_holder["value"] = {
"output": output,
"returncode": exit_code,
}
except Exception as e:
result_holder["error"] = e
t = threading.Thread(target=_run, daemon=True)
t.start()
while t.is_alive():
t.join(timeout=0.2)
if is_interrupted():
try:
self._worker.run_coroutine(
self._sandbox.terminate.aio(),
timeout=15,
)
except Exception:
pass
return {
"output": "[Command interrupted - Modal sandbox terminated]",
"returncode": 130,
}
if result_holder["error"]:
return {
"output": f"Modal execution error: {result_holder['error']}",
"returncode": 1,
}
return result_holder["value"]
def cleanup(self):
"""Snapshot the filesystem (if persistent) then stop the sandbox."""
if self._sandbox is None:
return
if self._persistent:
try:
async def _snapshot():
img = await self._sandbox.snapshot_filesystem.aio()
return img.object_id
try:
snapshot_id = self._worker.run_coroutine(_snapshot(), timeout=60)
except Exception:
snapshot_id = None
if snapshot_id:
_store_direct_snapshot(self._task_id, snapshot_id)
logger.info(
"Modal: saved filesystem snapshot %s for task %s",
snapshot_id[:20],
self._task_id,
)
except Exception as e:
logger.warning("Modal: filesystem snapshot failed: %s", e)
try:
self._worker.run_coroutine(
self._sandbox.terminate.aio(),
timeout=15,
)
except Exception:
pass
finally:
self._worker.stop()
self._sandbox = None
self._app = None