Files
bot-bottle/bot_bottle/backend/smolmachines/bottle.py
T
didericis-claude dd99c495f4 fix(smolmachines): use sh -c not sh -lc in exec_agent
The terminal-decoration wrapper script is invoked with sh -lc, which
sources login-shell init files (/etc/profile, ~/.profile) rather than
interactive-shell files (~/.zshrc). smolvm is typically installed via
homebrew whose PATH setup lands in ~/.zprofile or ~/.zshrc — not picked
up by sh -l — so pty_resize.py's Popen(["smolvm", ...]) raises
FileNotFoundError, pty_resize exits non-zero, and the trailing reset-
printf makes sh exit 0. The caller sees "session ended (exit 0)"
immediately with no agent output.

Use sh -c instead. The calling process (./cli.py) inherits the user's
interactive shell PATH where smolvm is present, confirmed by the
provision steps (machine_exec) succeeding before exec_agent is reached.
2026-06-23 16:53:41 -04:00

204 lines
8.4 KiB
Python

"""SmolmachinesBottle — running-instance handle (PRD 0023 chunk 2d).
Routes `exec_agent` / `exec` / `cp_in` through `smolvm machine
exec` / `smolvm machine cp`. The handle is yielded by `launch`
and torn down via the surrounding ExitStack on context exit;
`close` is a no-op idempotent alias so the BottleBackend ABC's
context-manager contract is satisfied.
User context: `smolvm machine exec` runs commands as root in the
VM, but the agent image's USER is `node` and agent CLIs may refuse
to run as root in bypass modes. Both
`exec_agent` and `exec` switch to the requested user (default
`node`) via `runuser -u <user> --` and set `HOME` / `USER`
through `smolvm -e` — avoiding `runuser -l`'s login-shell wiring
(PAM session setup, /etc/profile sourcing) which can hang on a
minimal Debian VM with no PAM session config."""
from __future__ import annotations
import subprocess
import sys
import time
import shlex
from typing import Mapping, cast
from ...agent_provider import PromptMode, prompt_args
from .. import Bottle, ExecResult
from ..terminal import exec_shell_script
from . import pty_resize as _pty_resize
from . import smolvm as _smolvm
# Absolute path to the pty_resize wrapper. Invoke as
# `python <path>` rather than `python -m <dotted-path>` so the
# wrapper runs regardless of cwd / sys.path — it has no
# bot_bottle.* imports, so it's self-contained.
_PTY_RESIZE_SCRIPT = _pty_resize.__file__
# Per-user env the agent image's USER (node) expects. Some providers
# write session state under the user's home directory;
# bare `runuser -u` inherits root's HOME=/root, which claude
# can't write to. Set HOME / USER explicitly through smolvm -e
# so the child process sees them.
_HOME_FOR = {
"node": "/home/node",
"root": "/root",
}
def _env_assignments_for(user: str, env: Mapping[str, str]) -> list[str]:
home = _HOME_FOR.get(user, f"/home/{user}")
out = [f"HOME={home}", f"USER={user}"]
for k, v in env.items():
out.append(f"{k}={v}")
return out
class SmolmachinesBottle(Bottle):
"""Handle returned by `SmolmachinesBottleBackend.launch`. The
underlying VM lifecycle (create / start / stop / delete) lives
on the launch ExitStack — this class only routes runtime
operations to the right `smolvm machine ...` subcommand."""
def __init__(
self,
machine_name: str,
*,
prompt_path: str | None = None,
guest_env: Mapping[str, str] | None = None,
agent_command: str = "claude",
agent_prompt_mode: PromptMode = "append_file",
agent_provider_template: str = "claude",
terminal_title: str = "",
terminal_color: str = "",
agent_workdir: str = "/home/node",
) -> None:
self.name = machine_name
# In-VM path to the agent's prompt file. None when the
# agent declared no prompt (file still exists; we just
# don't pass --append-system-prompt-file).
self.prompt_path = prompt_path
# Env vars the agent process needs (HTTPS_PROXY,
# CLAUDE_CODE_OAUTH_TOKEN, manifest-declared bottle env, …).
# Forwarded on every `smolvm machine exec` via `-e K=V`
# because exec doesn't inherit from machine_create's env.
self._guest_env = dict(guest_env or {})
self._agent_prompt_mode = agent_prompt_mode
self.agent_command = agent_command
self.terminal_title = terminal_title
self.terminal_color = terminal_color
self.agent_provider_template = agent_provider_template
self.agent_workdir = agent_workdir
def agent_argv(
self, argv: list[str], *, tty: bool = True,
) -> list[str]:
flags = ["smolvm", "machine", "exec", "--name", self.name]
if tty:
flags += ["-i", "-t"]
agent_tail = ["env", *_env_assignments_for("node", self._guest_env)]
if self.agent_workdir and self.agent_workdir != _HOME_FOR["node"]:
agent_tail += [
"sh", "-lc",
f"cd {shlex.quote(self.agent_workdir)} && exec \"$@\"",
"bot-bottle-agent",
]
agent_tail.append(self.agent_command)
provider_prompt_args = prompt_args(
cast(PromptMode, self._agent_prompt_mode), self.prompt_path, argv=argv,
)
if cast(PromptMode, self._agent_prompt_mode) == "read_prompt_file":
agent_tail += argv
agent_tail += provider_prompt_args
else:
agent_tail += provider_prompt_args
agent_tail += argv
flags += ["--", "runuser", "-u", "node", "--", *agent_tail]
if not tty:
# No PTY allocated — no SIGWINCH to forward, no resize
# bridge needed. Skip the wrapper so non-interactive
# exec paths (e.g., provisioning shell-outs that
# happen to go through this method) stay light.
return flags
return [
sys.executable, _PTY_RESIZE_SCRIPT,
self.name, "--", *flags,
]
def exec_agent(self, argv: list[str], *, tty: bool = True) -> int:
"""Run the selected agent interactively inside the VM as the `node`
user. Inherits the operator's terminal (stdin / stdout /
stderr) so the session feels native. Blocks until the agent
exits; returns the in-VM exit code.
We bypass the captured-output `machine_exec` helper here
because that one wraps stdout/stderr in pipes — fine for
scripted exec, wrong for an interactive shell. Drop down
to `subprocess.run` with the TTY inherited.
UID switches via `runuser -u node --` (not `-l`) so we
avoid login-shell wiring. HOME / USER come from `smolvm
-e` instead, which sets them on the process env."""
agent_argv = self.agent_argv(argv, tty=tty)
script = exec_shell_script(agent_argv, self.terminal_title, self.terminal_color) if tty else None
if script is None:
return subprocess.run(agent_argv, check=False).returncode
# Use sh -c (not -lc) so the script inherits PATH from the calling
# process. sh -l sources login-shell init files (e.g. /etc/profile)
# which may NOT include smolvm's location when it was installed via
# homebrew. The calling process (./cli.py) already has smolvm on PATH
# (provision steps succeed), so -c is sufficient.
return subprocess.run(["sh", "-c", script], check=False).returncode
# smolvm/libkrun can SIGKILL an otherwise-normal exec during
# early-VM provisioning. Retry once after a short settle so
# callers (provision_ca, etc.) don't have to handle it themselves.
_SIGKILL_EXIT = 128 + 9
def exec(self, script: str, *, user: str = "node") -> ExecResult:
"""Run a POSIX shell script as `user` (default `node`) and
capture the result. Matches the docker backend's `exec`,
which defaults to the image's USER (also node) — so test
helpers / provision shell-outs run with the same identity
on both backends. Pass `user="root"` for tests that need
root.
`runuser -u <user> -- env ... /bin/sh -c <script>` switches UID
without invoking a login shell, then sets HOME / USER and the
bottle env in the child process.
Retries once on SIGKILL (exit 137) — libkrun occasionally
kills short-lived execs during VM bring-up."""
r = self._exec_raw(script, user=user)
if r.returncode == self._SIGKILL_EXIT:
time.sleep(1.0)
r = self._exec_raw(script, user=user)
return r
def _exec_raw(self, script: str, *, user: str = "node") -> ExecResult:
argv = [
"--", "runuser", "-u", user, "--",
"env", *_env_assignments_for(user, self._guest_env),
"/bin/sh", "-c", script,
]
r = subprocess.run(
["smolvm", "machine", "exec", "--name", self.name] + argv,
capture_output=True, text=True, check=False,
)
return ExecResult(
returncode=r.returncode,
stdout=r.stdout or "",
stderr=r.stderr or "",
)
def cp_in(self, host_path: str, container_path: str) -> None:
"""Copy a host path into the guest at `container_path`."""
_smolvm.machine_cp(host_path, f"{self.name}:{container_path}")
def close(self) -> None:
# Real teardown lives on the launch ExitStack; this is just
# the idempotent alias the BottleBackend ABC expects.
pass