unsloth/unsloth_cli/commands/studio.py
Daniel Han 797ddd201e
Fix Studio silently exiting on Windows without error output (#4527)
* Fix Studio silently exiting on Windows without error output

On Windows, `unsloth studio` launches a child process via
subprocess.Popen to run the server in the studio venv. If the child
crashes (e.g. due to a missing package), the parent just calls
typer.Exit(rc) with no message -- the user sees "Launching Unsloth
Studio... Please wait..." and then the prompt returns with zero
feedback.

Root cause: `data_designer_unstructured_seed` is imported at the top
level in seed.py. If this package is not installed in the studio venv,
the entire import chain (seed.py -> routes/__init__.py -> main.py ->
run_server()) crashes with ModuleNotFoundError. Since run.py has no
try/except around run_server() and studio.py does not report nonzero
exit codes, the failure is completely silent.

Changes:
- run.py: wrap run_server() in try/except, print clear error with
  traceback to stderr. Also reconfigure stderr encoding on Windows so
  tracebacks with non-ASCII paths do not cause secondary failures.
- studio.py: print an error message when the child process exits with
  a nonzero code on Windows, so the user knows something went wrong.
- seed.py: make data_designer_unstructured_seed import optional with
  a try/except fallback. The server starts normally and only returns
  HTTP 500 if the unstructured seed endpoints are actually called.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Skip Anaconda/Miniconda Python when creating Studio venv on Windows

Conda-bundled CPython ships modified DLL search paths that prevent
torch from loading c10.dll on Windows. The Studio server fails
silently at startup because the venv was created with conda's Python.

Standalone CPython (python.org, winget, uv) does not have this issue.

Both install.ps1 and setup.ps1 now skip any Python binary whose path
contains conda, miniconda, anaconda, miniforge, or mambaforge when
selecting the interpreter for the studio venv. If only conda Python
is available, the scripts print an error with instructions to install
standalone CPython.

* Fix multi-file preview crash and improve setup.ps1 Python discovery

Addresses review findings [10/10] and [8/10]:

1. seed.py: _read_preview_rows_from_multi_files() had a hard import
   of build_multi_file_preview_rows inside the function body, bypassing
   the optional-plugin guard. Moved it into the top-level try/except
   block and added a None guard matching the other functions.

2. setup.ps1: Python discovery now probes py.exe (Python Launcher)
   first, uses Get-Command -All to look past conda entries that shadow
   standalone CPython further down PATH, skips WindowsApps stubs, and
   resolves the actual executable path so venv creation does not
   re-resolve back to a conda interpreter.

* [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci

* Check sys.base_prefix to catch venvs created from conda Python

A venv created from conda Python (e.g. C:\Users\danie\.venv) has a
path that does not contain "conda", but sys.base_prefix still points
to the conda install (e.g. C:\Users\danie\miniconda3). The previous
path-only check missed this case entirely.

Both install.ps1 and setup.ps1 now use a Test-IsConda helper that
checks both the executable path AND sys.base_prefix against the
conda/miniconda/anaconda/miniforge/mambaforge pattern. This catches:
- Direct conda Python executables
- Venvs created from conda Python (base_prefix reveals the origin)

* Fix install.ps1 passing version string to uv venv instead of resolved path

Find-CompatiblePython returned a bare version string (e.g. "3.13")
which was passed to `uv venv --python 3.13`. uv performs its own
interpreter discovery and can resolve that version string back to a
conda Python, defeating the entire conda-skip logic.

Now Find-CompatiblePython returns a hashtable with both .Version (for
display) and .Path (the resolved absolute executable path). The venv
is created with `uv venv --python <absolute-path>`, ensuring uv uses
the exact interpreter we validated.

* Quote resolved Python path in uv venv call for paths with spaces

---------

Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>
2026-03-22 08:23:03 -07:00

213 lines
7.4 KiB
Python

# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2026-present the Unsloth AI Inc. team. All rights reserved. See /studio/LICENSE.AGPL-3.0
import os
import platform
import subprocess
import sys
import time
from pathlib import Path
from typing import Optional
import typer
studio_app = typer.Typer(help = "Unsloth Studio commands.")
STUDIO_HOME = Path.home() / ".unsloth" / "studio"
# __file__ is unsloth_cli/commands/studio.py -- two parents up is the package root
# (either site-packages or the repo root for editable installs).
_PACKAGE_ROOT = Path(__file__).resolve().parent.parent.parent
def _studio_venv_python() -> Optional[Path]:
"""Return the studio venv Python binary, or None if not set up."""
if platform.system() == "Windows":
p = STUDIO_HOME / ".venv" / "Scripts" / "python.exe"
else:
p = STUDIO_HOME / ".venv" / "bin" / "python"
return p if p.is_file() else None
def _find_run_py() -> Optional[Path]:
"""Find studio/backend/run.py.
No CWD dependency — works from any directory.
Since studio/ is now a proper package (has __init__.py), it lives in
site-packages after pip install, right next to unsloth_cli/.
"""
# 1. Relative to __file__ (site-packages or editable repo root)
run_py = _PACKAGE_ROOT / "studio" / "backend" / "run.py"
if run_py.is_file():
return run_py
# 2. Studio venv's site-packages (Linux + Windows layouts)
for pattern in (
"lib/python*/site-packages/studio/backend/run.py",
"Lib/site-packages/studio/backend/run.py",
):
for match in (STUDIO_HOME / ".venv").glob(pattern):
return match
return None
def _find_setup_script() -> Optional[Path]:
"""Find studio/setup.sh or studio/setup.ps1.
No CWD dependency — works from any directory.
"""
name = "setup.ps1" if platform.system() == "Windows" else "setup.sh"
# 1. Relative to __file__ (site-packages or editable repo root)
s = _PACKAGE_ROOT / "studio" / name
if s.is_file():
return s
# 2. Studio venv's site-packages
for pattern in (
f"lib/python*/site-packages/studio/{name}",
f"Lib/site-packages/studio/{name}",
):
for match in (STUDIO_HOME / ".venv").glob(pattern):
return match
return None
# ── unsloth studio (server) ──────────────────────────────────────────
@studio_app.callback(invoke_without_command = True)
def studio_default(
ctx: typer.Context,
port: int = typer.Option(8888, "--port", "-p"),
host: str = typer.Option("0.0.0.0", "--host", "-H"),
frontend: Optional[Path] = typer.Option(None, "--frontend", "-f"),
silent: bool = typer.Option(False, "--silent", "-q"),
):
"""Launch the Unsloth Studio server."""
if ctx.invoked_subcommand is not None:
return
# Always use the studio venv if it exists and we're not already in it
studio_venv_dir = STUDIO_HOME / ".venv"
in_studio_venv = sys.prefix.startswith(str(studio_venv_dir))
if not in_studio_venv:
studio_python = _studio_venv_python()
run_py = _find_run_py()
if studio_python and run_py:
if not silent:
typer.echo("Launching Unsloth Studio... Please wait...")
args = [
str(studio_python),
str(run_py),
"--host",
host,
"--port",
str(port),
]
if frontend:
args.extend(["--frontend", str(frontend)])
if silent:
args.append("--silent")
# On Windows, os.execvp() spawns a child but the parent lingers,
# so Ctrl+C only kills the parent leaving the child orphaned.
# Use subprocess.run() on Windows so the parent waits for the child.
if sys.platform == "win32":
import subprocess as _sp
proc = _sp.Popen(args)
try:
rc = proc.wait()
except KeyboardInterrupt:
# Child has its own signal handler — let it finish
rc = proc.wait()
if rc != 0:
typer.echo(
f"\nError: Studio server exited unexpectedly (code {rc}).",
err = True,
)
typer.echo(
"Check the error above. If a package is missing, "
"re-run: unsloth studio setup",
err = True,
)
raise typer.Exit(rc)
else:
os.execvp(str(studio_python), args)
else:
typer.echo("Studio not set up. Run 'unsloth studio setup' first.")
raise typer.Exit(1)
from studio.backend.run import run_server
if not silent:
from studio.backend.run import _resolve_external_ip
display_host = _resolve_external_ip() if host == "0.0.0.0" else host
typer.echo(f"Starting Unsloth Studio on http://{display_host}:{port}")
run_kwargs = dict(host = host, port = port, silent = silent)
if frontend is not None:
run_kwargs["frontend_path"] = frontend
run_server(**run_kwargs)
from studio.backend.run import _shutdown_event
try:
if _shutdown_event is not None:
# NOTE: Event.wait() without a timeout blocks at the C level
# on Linux, preventing Python from delivering SIGINT (Ctrl+C).
while not _shutdown_event.is_set():
_shutdown_event.wait(timeout = 1)
else:
while True:
time.sleep(1)
except KeyboardInterrupt:
from studio.backend.run import _graceful_shutdown, _server
_graceful_shutdown(_server)
typer.echo("\nShutting down...")
# ── unsloth studio setup ─────────────────────────────────────────────
@studio_app.command()
def setup():
"""Run one-time Studio environment setup."""
script = _find_setup_script()
if not script:
typer.echo("Error: Could not find setup script (setup.sh / setup.ps1).")
raise typer.Exit(1)
if platform.system() == "Windows":
result = subprocess.run(
["powershell", "-ExecutionPolicy", "Bypass", "-File", str(script)],
)
else:
result = subprocess.run(["bash", str(script)])
if result.returncode != 0:
raise typer.Exit(result.returncode)
# ── unsloth studio reset-password ────────────────────────────────────
@studio_app.command("reset-password")
def reset_password():
"""Reset the Studio admin password.
Deletes the auth database so that a fresh admin account with a new
random password is created on the next server start. The Studio
server must be restarted after running this command.
"""
auth_dir = STUDIO_HOME / "auth"
db_file = auth_dir / "auth.db"
pw_file = auth_dir / ".bootstrap_password"
if not db_file.exists():
typer.echo("No auth database found -- nothing to reset.")
raise typer.Exit(0)
db_file.unlink(missing_ok = True)
pw_file.unlink(missing_ok = True)
typer.echo("Auth database deleted. Restart Unsloth Studio to get a new password.")