Sybren A. Stüvel
337a5f352c
Also contains a SubprocMixin mix-in class that can help to write operators that run & monitor subprocesses. Messages sent back & forth between Blender and the subprocess MUST subclass either BlenderMessage or SubprocMessage.
135 lines
4.0 KiB
Python
135 lines
4.0 KiB
Python
"""
|
|
All the stuff that needs to run in a subprocess.
|
|
"""
|
|
|
|
import logging
|
|
import pathlib
|
|
|
|
|
|
class Message:
|
|
"""Superclass for all message sent over pipes."""
|
|
|
|
|
|
class BlenderMessage(Message):
|
|
"""Superclass for all messages sent from Blender to the subprocess."""
|
|
|
|
|
|
class SubprocMessage(Message):
|
|
"""Superclass for all messages sent from the subprocess to Blender."""
|
|
|
|
|
|
class Abort(BlenderMessage):
|
|
"""Sent when the user requests abortion of a task."""
|
|
|
|
|
|
class Progress(SubprocMessage):
|
|
"""Send from subprocess to Blender to report progress.
|
|
|
|
:ivar progress: the progress percentage, from 0-1.
|
|
"""
|
|
|
|
def __init__(self, progress: float):
|
|
self.progress = progress
|
|
|
|
|
|
class DownloadError(SubprocMessage):
|
|
"""Sent when there was an error downloading something."""
|
|
|
|
def __init__(self, status_code: int, description: str):
|
|
self.status_code = status_code
|
|
self.description = description
|
|
|
|
|
|
class Success(SubprocMessage):
|
|
"""Sent when an operation finished sucessfully."""
|
|
|
|
|
|
class Aborted(SubprocMessage):
|
|
"""Sent as response to Abort message."""
|
|
|
|
|
|
def _download(pipe_to_blender, package_url: str, download_dir: pathlib.Path) -> pathlib.Path:
|
|
"""Downloads the given package
|
|
|
|
:returns: path to the downloaded file, or None in case of error.
|
|
"""
|
|
|
|
import requests
|
|
|
|
log = logging.getLogger('%s.download' % __name__)
|
|
log.info('Going to download %s to %s', package_url, download_dir)
|
|
pipe_to_blender.send(Progress(0.0))
|
|
|
|
log.info('Downloading %s', package_url)
|
|
resp = requests.get(package_url, stream=True, verify=True)
|
|
|
|
try:
|
|
resp.raise_for_status()
|
|
except requests.HTTPError as ex:
|
|
log.error('Error downloading %s: %s', package_url, ex)
|
|
pipe_to_blender.send(DownloadError(resp.status_code, str(ex)))
|
|
return None
|
|
|
|
try:
|
|
# Use float so that we can also use infinity
|
|
content_length = float(resp.headers['content-length'])
|
|
except KeyError:
|
|
log.warning('Server did not send content length, cannot report progress.')
|
|
content_length = float('inf')
|
|
|
|
# TODO: get filename from Content-Disposition header, if available.
|
|
# TODO: use urllib.parse to parse the URL.
|
|
local_filename = package_url.split('/')[-1] or 'download.tmp'
|
|
local_fpath = download_dir / local_filename
|
|
|
|
downloaded_length = 0
|
|
with local_fpath.open('wb') as outfile:
|
|
for chunk in resp.iter_content(chunk_size=1024 ** 2):
|
|
# Handle abort messages from Blender
|
|
while pipe_to_blender.poll():
|
|
recvd = pipe_to_blender.recv()
|
|
if isinstance(recvd, Abort):
|
|
log.warning('Aborting download of %s by request', package_url)
|
|
pipe_to_blender.send(Aborted())
|
|
return None
|
|
log.warning('Unknown message %s received, ignoring', recvd)
|
|
|
|
if not chunk: # filter out keep-alive new chunks
|
|
continue
|
|
|
|
outfile.write(chunk)
|
|
|
|
downloaded_length += len(chunk)
|
|
|
|
# TODO: use multiplier for progress, so that we can count up to 70% and
|
|
# leave 30% "progress" for installation of the package.
|
|
pipe_to_blender.send(Progress(downloaded_length / content_length))
|
|
|
|
pipe_to_blender.send(Success())
|
|
return local_fpath
|
|
|
|
|
|
def download_and_install(pipe_to_blender, package_url: str):
|
|
"""Downloads and installs the given package."""
|
|
|
|
from . import cache
|
|
|
|
log = logging.getLogger('%s.download_and_install' % __name__)
|
|
|
|
cache_dir = cache.cache_directory('downloads')
|
|
downloaded = _download(pipe_to_blender, package_url, cache_dir)
|
|
|
|
if not downloaded:
|
|
log.debug('Download failed/aborted, not going to install anything.')
|
|
return
|
|
|
|
# TODO: actually install the package
|
|
log.warning('Installing is not actually implemented, install %s yourself.', downloaded)
|
|
|
|
|
|
def debug_hang():
|
|
"""Hangs for an hour. For testing purposes only."""
|
|
|
|
import time
|
|
time.sleep(3600)
|