Poodletooth-iLand/panda/python/Lib/site-packages/pip/download.py
2015-04-10 07:57:49 -04:00

913 lines
31 KiB
Python

from __future__ import absolute_import
import cgi
import email.utils
import hashlib
import getpass
import json
import logging
import mimetypes
import os
import platform
import re
import shutil
import sys
import tempfile
from pip._vendor.six.moves.urllib import parse as urllib_parse
from pip._vendor.six.moves.urllib import request as urllib_request
import pip
from pip.exceptions import InstallationError, HashMismatch
from pip.models import PyPI
from pip.utils import (splitext, rmtree, format_size, display_path,
backup_dir, ask_path_exists, unpack_file,
call_subprocess)
from pip.utils.filesystem import check_path_owner
from pip.utils.logging import indent_log
from pip.utils.ui import DownloadProgressBar, DownloadProgressSpinner
from pip.locations import write_delete_marker_file
from pip.vcs import vcs
from pip._vendor import requests, six
from pip._vendor.requests.adapters import BaseAdapter, HTTPAdapter
from pip._vendor.requests.auth import AuthBase, HTTPBasicAuth
from pip._vendor.requests.models import Response
from pip._vendor.requests.structures import CaseInsensitiveDict
from pip._vendor.requests.packages import urllib3
from pip._vendor.cachecontrol import CacheControlAdapter
from pip._vendor.cachecontrol.caches import FileCache
from pip._vendor.lockfile import LockError
from pip._vendor.six.moves import xmlrpc_client
__all__ = ['get_file_content',
'is_url', 'url_to_path', 'path_to_url',
'is_archive_file', 'unpack_vcs_link',
'unpack_file_url', 'is_vcs_url', 'is_file_url',
'unpack_http_url', 'unpack_url']
logger = logging.getLogger(__name__)
def user_agent():
"""
Return a string representing the user agent.
"""
data = {
"installer": {"name": "pip", "version": pip.__version__},
"python": platform.python_version(),
"implementation": {
"name": platform.python_implementation(),
},
}
if data["implementation"]["name"] == 'CPython':
data["implementation"]["version"] = platform.python_version()
elif data["implementation"]["name"] == 'PyPy':
if sys.pypy_version_info.releaselevel == 'final':
pypy_version_info = sys.pypy_version_info[:3]
else:
pypy_version_info = sys.pypy_version_info
data["implementation"]["version"] = ".".join(
[str(x) for x in pypy_version_info]
)
elif data["implementation"]["name"] == 'Jython':
# Complete Guess
data["implementation"]["version"] = platform.python_version()
elif data["implementation"]["name"] == 'IronPython':
# Complete Guess
data["implementation"]["version"] = platform.python_version()
if sys.platform.startswith("linux"):
distro = dict(filter(
lambda x: x[1],
zip(["name", "version", "id"], platform.linux_distribution()),
))
libc = dict(filter(
lambda x: x[1],
zip(["lib", "version"], platform.libc_ver()),
))
if libc:
distro["libc"] = libc
if distro:
data["distro"] = distro
if sys.platform.startswith("darwin") and platform.mac_ver()[0]:
data["distro"] = {"name": "OS X", "version": platform.mac_ver()[0]}
if platform.system():
data.setdefault("system", {})["name"] = platform.system()
if platform.release():
data.setdefault("system", {})["release"] = platform.release()
if platform.machine():
data["cpu"] = platform.machine()
return "{data[installer][name]}/{data[installer][version]} {json}".format(
data=data,
json=json.dumps(data, separators=(",", ":"), sort_keys=True),
)
class MultiDomainBasicAuth(AuthBase):
def __init__(self, prompting=True):
self.prompting = prompting
self.passwords = {}
def __call__(self, req):
parsed = urllib_parse.urlparse(req.url)
# Get the netloc without any embedded credentials
netloc = parsed.netloc.rsplit("@", 1)[-1]
# Set the url of the request to the url without any credentials
req.url = urllib_parse.urlunparse(parsed[:1] + (netloc,) + parsed[2:])
# Use any stored credentials that we have for this netloc
username, password = self.passwords.get(netloc, (None, None))
# Extract credentials embedded in the url if we have none stored
if username is None:
username, password = self.parse_credentials(parsed.netloc)
if username or password:
# Store the username and password
self.passwords[netloc] = (username, password)
# Send the basic auth with this request
req = HTTPBasicAuth(username or "", password or "")(req)
# Attach a hook to handle 401 responses
req.register_hook("response", self.handle_401)
return req
def handle_401(self, resp, **kwargs):
# We only care about 401 responses, anything else we want to just
# pass through the actual response
if resp.status_code != 401:
return resp
# We are not able to prompt the user so simple return the response
if not self.prompting:
return resp
parsed = urllib_parse.urlparse(resp.url)
# Prompt the user for a new username and password
username = six.moves.input("User for %s: " % parsed.netloc)
password = getpass.getpass("Password: ")
# Store the new username and password to use for future requests
if username or password:
self.passwords[parsed.netloc] = (username, password)
# Consume content and release the original connection to allow our new
# request to reuse the same one.
resp.content
resp.raw.release_conn()
# Add our new username and password to the request
req = HTTPBasicAuth(username or "", password or "")(resp.request)
# Send our new request
new_resp = resp.connection.send(req, **kwargs)
new_resp.history.append(resp)
return new_resp
def parse_credentials(self, netloc):
if "@" in netloc:
userinfo = netloc.rsplit("@", 1)[0]
if ":" in userinfo:
return userinfo.split(":", 1)
return userinfo, None
return None, None
class LocalFSAdapter(BaseAdapter):
def send(self, request, stream=None, timeout=None, verify=None, cert=None,
proxies=None):
pathname = url_to_path(request.url)
resp = Response()
resp.status_code = 200
resp.url = request.url
try:
stats = os.stat(pathname)
except OSError as exc:
resp.status_code = 404
resp.raw = exc
else:
modified = email.utils.formatdate(stats.st_mtime, usegmt=True)
content_type = mimetypes.guess_type(pathname)[0] or "text/plain"
resp.headers = CaseInsensitiveDict({
"Content-Type": content_type,
"Content-Length": stats.st_size,
"Last-Modified": modified,
})
resp.raw = open(pathname, "rb")
resp.close = resp.raw.close
return resp
def close(self):
pass
class SafeFileCache(FileCache):
"""
A file based cache which is safe to use even when the target directory may
not be accessible or writable.
"""
def __init__(self, *args, **kwargs):
super(SafeFileCache, self).__init__(*args, **kwargs)
# Check to ensure that the directory containing our cache directory
# is owned by the user current executing pip. If it does not exist
# we will check the parent directory until we find one that does exist.
# If it is not owned by the user executing pip then we will disable
# the cache and log a warning.
if not check_path_owner(self.directory):
logger.warning(
"The directory '%s' or its parent directory is not owned by "
"the current user and the cache has been disabled. Please "
"check the permissions and owner of that directory. If "
"executing pip with sudo, you may want sudo's -H flag.",
self.directory,
)
# Set our directory to None to disable the Cache
self.directory = None
def get(self, *args, **kwargs):
# If we don't have a directory, then the cache should be a no-op.
if self.directory is None:
return
try:
return super(SafeFileCache, self).get(*args, **kwargs)
except (LockError, OSError, IOError):
# We intentionally silence this error, if we can't access the cache
# then we can just skip caching and process the request as if
# caching wasn't enabled.
pass
def set(self, *args, **kwargs):
# If we don't have a directory, then the cache should be a no-op.
if self.directory is None:
return
try:
return super(SafeFileCache, self).set(*args, **kwargs)
except (LockError, OSError, IOError):
# We intentionally silence this error, if we can't access the cache
# then we can just skip caching and process the request as if
# caching wasn't enabled.
pass
def delete(self, *args, **kwargs):
# If we don't have a directory, then the cache should be a no-op.
if self.directory is None:
return
try:
return super(SafeFileCache, self).delete(*args, **kwargs)
except (LockError, OSError, IOError):
# We intentionally silence this error, if we can't access the cache
# then we can just skip caching and process the request as if
# caching wasn't enabled.
pass
class InsecureHTTPAdapter(HTTPAdapter):
def cert_verify(self, conn, url, verify, cert):
conn.cert_reqs = 'CERT_NONE'
conn.ca_certs = None
class PipSession(requests.Session):
timeout = None
def __init__(self, *args, **kwargs):
retries = kwargs.pop("retries", 0)
cache = kwargs.pop("cache", None)
insecure_hosts = kwargs.pop("insecure_hosts", [])
super(PipSession, self).__init__(*args, **kwargs)
# Attach our User Agent to the request
self.headers["User-Agent"] = user_agent()
# Attach our Authentication handler to the session
self.auth = MultiDomainBasicAuth()
# Create our urllib3.Retry instance which will allow us to customize
# how we handle retries.
retries = urllib3.Retry(
# Set the total number of retries that a particular request can
# have.
total=retries,
# A 503 error from PyPI typically means that the Fastly -> Origin
# connection got interupted in some way. A 503 error in general
# is typically considered a transient error so we'll go ahead and
# retry it.
status_forcelist=[503],
# Add a small amount of back off between failed requests in
# order to prevent hammering the service.
backoff_factor=0.25,
)
# We want to _only_ cache responses on securely fetched origins. We do
# this because we can't validate the response of an insecurely fetched
# origin, and we don't want someone to be able to poison the cache and
# require manual evication from the cache to fix it.
if cache:
secure_adapter = CacheControlAdapter(
cache=SafeFileCache(cache),
max_retries=retries,
)
else:
secure_adapter = HTTPAdapter(max_retries=retries)
# Our Insecure HTTPAdapter disables HTTPS validation. It does not
# support caching (see above) so we'll use it for all http:// URLs as
# well as any https:// host that we've marked as ignoring TLS errors
# for.
insecure_adapter = InsecureHTTPAdapter(max_retries=retries)
self.mount("https://", secure_adapter)
self.mount("http://", insecure_adapter)
# Enable file:// urls
self.mount("file://", LocalFSAdapter())
# We want to use a non-validating adapter for any requests which are
# deemed insecure.
for host in insecure_hosts:
self.mount("https://{0}/".format(host), insecure_adapter)
def request(self, method, url, *args, **kwargs):
# Allow setting a default timeout on a session
kwargs.setdefault("timeout", self.timeout)
# Dispatch the actual request
return super(PipSession, self).request(method, url, *args, **kwargs)
def get_file_content(url, comes_from=None, session=None):
"""Gets the content of a file; it may be a filename, file: URL, or
http: URL. Returns (location, content). Content is unicode."""
if session is None:
raise TypeError(
"get_file_content() missing 1 required keyword argument: 'session'"
)
match = _scheme_re.search(url)
if match:
scheme = match.group(1).lower()
if (scheme == 'file' and comes_from and
comes_from.startswith('http')):
raise InstallationError(
'Requirements file %s references URL %s, which is local'
% (comes_from, url))
if scheme == 'file':
path = url.split(':', 1)[1]
path = path.replace('\\', '/')
match = _url_slash_drive_re.match(path)
if match:
path = match.group(1) + ':' + path.split('|', 1)[1]
path = urllib_parse.unquote(path)
if path.startswith('/'):
path = '/' + path.lstrip('/')
url = path
else:
# FIXME: catch some errors
resp = session.get(url)
resp.raise_for_status()
if six.PY3:
return resp.url, resp.text
else:
return resp.url, resp.content
try:
with open(url) as f:
content = f.read()
except IOError as exc:
raise InstallationError(
'Could not open requirements file: %s' % str(exc)
)
return url, content
_scheme_re = re.compile(r'^(http|https|file):', re.I)
_url_slash_drive_re = re.compile(r'/*([a-z])\|', re.I)
def is_url(name):
"""Returns true if the name looks like a URL"""
if ':' not in name:
return False
scheme = name.split(':', 1)[0].lower()
return scheme in ['http', 'https', 'file', 'ftp'] + vcs.all_schemes
def url_to_path(url):
"""
Convert a file: URL to a path.
"""
assert url.startswith('file:'), (
"You can only turn file: urls into filenames (not %r)" % url)
_, netloc, path, _, _ = urllib_parse.urlsplit(url)
# if we have a UNC path, prepend UNC share notation
if netloc:
netloc = '\\\\' + netloc
path = urllib_request.url2pathname(netloc + path)
return path
def path_to_url(path):
"""
Convert a path to a file: URL. The path will be made absolute and have
quoted path parts.
"""
path = os.path.normpath(os.path.abspath(path))
url = urllib_parse.urljoin('file:', urllib_request.pathname2url(path))
return url
def is_archive_file(name):
"""Return True if `name` is a considered as an archive file."""
archives = (
'.zip', '.tar.gz', '.tar.bz2', '.tgz', '.tar', '.whl'
)
ext = splitext(name)[1].lower()
if ext in archives:
return True
return False
def unpack_vcs_link(link, location, only_download=False):
vcs_backend = _get_used_vcs_backend(link)
if only_download:
vcs_backend.export(location)
else:
vcs_backend.unpack(location)
def _get_used_vcs_backend(link):
for backend in vcs.backends:
if link.scheme in backend.schemes:
vcs_backend = backend(link.url)
return vcs_backend
def is_vcs_url(link):
return bool(_get_used_vcs_backend(link))
def is_file_url(link):
return link.url.lower().startswith('file:')
def _check_hash(download_hash, link):
if download_hash.digest_size != hashlib.new(link.hash_name).digest_size:
logger.critical(
"Hash digest size of the package %d (%s) doesn't match the "
"expected hash name %s!",
download_hash.digest_size, link, link.hash_name,
)
raise HashMismatch('Hash name mismatch for package %s' % link)
if download_hash.hexdigest() != link.hash:
logger.critical(
"Hash of the package %s (%s) doesn't match the expected hash %s!",
link, download_hash.hexdigest(), link.hash,
)
raise HashMismatch(
'Bad %s hash for package %s' % (link.hash_name, link)
)
def _get_hash_from_file(target_file, link):
try:
download_hash = hashlib.new(link.hash_name)
except (ValueError, TypeError):
logger.warning(
"Unsupported hash name %s for package %s", link.hash_name, link,
)
return None
with open(target_file, 'rb') as fp:
while True:
chunk = fp.read(4096)
if not chunk:
break
download_hash.update(chunk)
return download_hash
def _progress_indicator(iterable, *args, **kwargs):
return iterable
def _download_url(resp, link, content_file):
download_hash = None
if link.hash and link.hash_name:
try:
download_hash = hashlib.new(link.hash_name)
except ValueError:
logger.warning(
"Unsupported hash name %s for package %s",
link.hash_name, link,
)
try:
total_length = int(resp.headers['content-length'])
except (ValueError, KeyError, TypeError):
total_length = 0
cached_resp = getattr(resp, "from_cache", False)
if logger.getEffectiveLevel() > logging.INFO:
show_progress = False
elif cached_resp:
show_progress = False
elif total_length > (40 * 1000):
show_progress = True
elif not total_length:
show_progress = True
else:
show_progress = False
show_url = link.show_url
def resp_read(chunk_size):
try:
# Special case for urllib3.
for chunk in resp.raw.stream(
chunk_size,
# We use decode_content=False here because we do
# want urllib3 to mess with the raw bytes we get
# from the server. If we decompress inside of
# urllib3 then we cannot verify the checksum
# because the checksum will be of the compressed
# file. This breakage will only occur if the
# server adds a Content-Encoding header, which
# depends on how the server was configured:
# - Some servers will notice that the file isn't a
# compressible file and will leave the file alone
# and with an empty Content-Encoding
# - Some servers will notice that the file is
# already compressed and will leave the file
# alone and will add a Content-Encoding: gzip
# header
# - Some servers won't notice anything at all and
# will take a file that's already been compressed
# and compress it again and set the
# Content-Encoding: gzip header
#
# By setting this not to decode automatically we
# hope to eliminate problems with the second case.
decode_content=False):
yield chunk
except AttributeError:
# Standard file-like object.
while True:
chunk = resp.raw.read(chunk_size)
if not chunk:
break
yield chunk
progress_indicator = _progress_indicator
if link.netloc == PyPI.netloc:
url = show_url
else:
url = link.url_without_fragment
if show_progress: # We don't show progress on cached responses
if total_length:
logger.info(
"Downloading %s (%s)", url, format_size(total_length),
)
progress_indicator = DownloadProgressBar(
max=total_length,
).iter
else:
logger.info("Downloading %s", url)
progress_indicator = DownloadProgressSpinner().iter
elif cached_resp:
logger.info("Using cached %s", url)
else:
logger.info("Downloading %s", url)
logger.debug('Downloading from URL %s', link)
for chunk in progress_indicator(resp_read(4096), 4096):
if download_hash is not None:
download_hash.update(chunk)
content_file.write(chunk)
if link.hash and link.hash_name:
_check_hash(download_hash, link)
return download_hash
def _copy_file(filename, location, content_type, link):
copy = True
download_location = os.path.join(location, link.filename)
if os.path.exists(download_location):
response = ask_path_exists(
'The file %s exists. (i)gnore, (w)ipe, (b)ackup ' %
display_path(download_location), ('i', 'w', 'b'))
if response == 'i':
copy = False
elif response == 'w':
logger.warning('Deleting %s', display_path(download_location))
os.remove(download_location)
elif response == 'b':
dest_file = backup_dir(download_location)
logger.warning(
'Backing up %s to %s',
display_path(download_location),
display_path(dest_file),
)
shutil.move(download_location, dest_file)
if copy:
shutil.copy(filename, download_location)
logger.info('Saved %s', display_path(download_location))
def unpack_http_url(link, location, download_dir=None, session=None):
if session is None:
raise TypeError(
"unpack_http_url() missing 1 required keyword argument: 'session'"
)
temp_dir = tempfile.mkdtemp('-unpack', 'pip-')
# If a download dir is specified, is the file already downloaded there?
already_downloaded_path = None
if download_dir:
already_downloaded_path = _check_download_dir(link, download_dir)
if already_downloaded_path:
from_path = already_downloaded_path
content_type = mimetypes.guess_type(from_path)[0]
else:
# let's download to a tmp dir
from_path, content_type = _download_http_url(link, session, temp_dir)
# unpack the archive to the build dir location. even when only downloading
# archives, they have to be unpacked to parse dependencies
unpack_file(from_path, location, content_type, link)
# a download dir is specified; let's copy the archive there
if download_dir and not already_downloaded_path:
_copy_file(from_path, download_dir, content_type, link)
if not already_downloaded_path:
os.unlink(from_path)
rmtree(temp_dir)
def unpack_file_url(link, location, download_dir=None):
"""Unpack link into location.
If download_dir is provided and link points to a file, make a copy
of the link file inside download_dir."""
link_path = url_to_path(link.url_without_fragment)
# If it's a url to a local directory
if os.path.isdir(link_path):
if os.path.isdir(location):
rmtree(location)
shutil.copytree(link_path, location, symlinks=True)
if download_dir:
logger.info('Link is a directory, ignoring download_dir')
return
# if link has a hash, let's confirm it matches
if link.hash:
link_path_hash = _get_hash_from_file(link_path, link)
_check_hash(link_path_hash, link)
# If a download dir is specified, is the file already there and valid?
already_downloaded_path = None
if download_dir:
already_downloaded_path = _check_download_dir(link, download_dir)
if already_downloaded_path:
from_path = already_downloaded_path
else:
from_path = link_path
content_type = mimetypes.guess_type(from_path)[0]
# unpack the archive to the build dir location. even when only downloading
# archives, they have to be unpacked to parse dependencies
unpack_file(from_path, location, content_type, link)
# a download dir is specified and not already downloaded
if download_dir and not already_downloaded_path:
_copy_file(from_path, download_dir, content_type, link)
def _copy_dist_from_dir(link_path, location):
"""Copy distribution files in `link_path` to `location`.
Invoked when user requests to install a local directory. E.g.:
pip install .
pip install ~/dev/git-repos/python-prompt-toolkit
"""
# Note: This is currently VERY SLOW if you have a lot of data in the
# directory, because it copies everything with `shutil.copytree`.
# What it should really do is build an sdist and install that.
# See https://github.com/pypa/pip/issues/2195
if os.path.isdir(location):
rmtree(location)
# build an sdist
setup_py = 'setup.py'
sdist_args = [sys.executable]
sdist_args.append('-c')
sdist_args.append(
"import setuptools, tokenize;__file__=%r;"
"exec(compile(getattr(tokenize, 'open', open)(__file__).read()"
".replace('\\r\\n', '\\n'), __file__, 'exec'))" % setup_py)
sdist_args.append('sdist')
sdist_args += ['--dist-dir', location]
logger.info('Running setup.py sdist for %s', link_path)
with indent_log():
call_subprocess(sdist_args, cwd=link_path, show_stdout=False)
# unpack sdist into `location`
sdist = os.path.join(location, os.listdir(location)[0])
logger.info('Unpacking sdist %s into %s', sdist, location)
unpack_file(sdist, location, content_type=None, link=None)
class PipXmlrpcTransport(xmlrpc_client.Transport):
"""Provide a `xmlrpclib.Transport` implementation via a `PipSession`
object.
"""
def __init__(self, index_url, session, use_datetime=False):
xmlrpc_client.Transport.__init__(self, use_datetime)
index_parts = urllib_parse.urlparse(index_url)
self._scheme = index_parts.scheme
self._session = session
def request(self, host, handler, request_body, verbose=False):
parts = (self._scheme, host, handler, None, None, None)
url = urllib_parse.urlunparse(parts)
try:
headers = {'Content-Type': 'text/xml'}
response = self._session.post(url, data=request_body,
headers=headers, stream=True)
response.raise_for_status()
self.verbose = verbose
return self.parse_response(response.raw)
except requests.HTTPError as exc:
logger.critical(
"HTTP error %s while getting %s",
exc.response.status_code, url,
)
raise
def unpack_url(link, location, download_dir=None,
only_download=False, session=None):
"""Unpack link.
If link is a VCS link:
if only_download, export into download_dir and ignore location
else unpack into location
for other types of link:
- unpack into location
- if download_dir, copy the file into download_dir
- if only_download, mark location for deletion
"""
# non-editable vcs urls
if is_vcs_url(link):
unpack_vcs_link(link, location, only_download)
# file urls
elif is_file_url(link):
unpack_file_url(link, location, download_dir)
if only_download:
write_delete_marker_file(location)
# http urls
else:
if session is None:
session = PipSession()
unpack_http_url(
link,
location,
download_dir,
session,
)
if only_download:
write_delete_marker_file(location)
def _download_http_url(link, session, temp_dir):
"""Download link url into temp_dir using provided session"""
target_url = link.url.split('#', 1)[0]
try:
resp = session.get(
target_url,
# We use Accept-Encoding: identity here because requests
# defaults to accepting compressed responses. This breaks in
# a variety of ways depending on how the server is configured.
# - Some servers will notice that the file isn't a compressible
# file and will leave the file alone and with an empty
# Content-Encoding
# - Some servers will notice that the file is already
# compressed and will leave the file alone and will add a
# Content-Encoding: gzip header
# - Some servers won't notice anything at all and will take
# a file that's already been compressed and compress it again
# and set the Content-Encoding: gzip header
# By setting this to request only the identity encoding We're
# hoping to eliminate the third case. Hopefully there does not
# exist a server which when given a file will notice it is
# already compressed and that you're not asking for a
# compressed file and will then decompress it before sending
# because if that's the case I don't think it'll ever be
# possible to make this work.
headers={"Accept-Encoding": "identity"},
stream=True,
)
resp.raise_for_status()
except requests.HTTPError as exc:
logger.critical(
"HTTP error %s while getting %s", exc.response.status_code, link,
)
raise
content_type = resp.headers.get('content-type', '')
filename = link.filename # fallback
# Have a look at the Content-Disposition header for a better guess
content_disposition = resp.headers.get('content-disposition')
if content_disposition:
type, params = cgi.parse_header(content_disposition)
# We use ``or`` here because we don't want to use an "empty" value
# from the filename param.
filename = params.get('filename') or filename
ext = splitext(filename)[1]
if not ext:
ext = mimetypes.guess_extension(content_type)
if ext:
filename += ext
if not ext and link.url != resp.url:
ext = os.path.splitext(resp.url)[1]
if ext:
filename += ext
file_path = os.path.join(temp_dir, filename)
with open(file_path, 'wb') as content_file:
_download_url(resp, link, content_file)
return file_path, content_type
def _check_download_dir(link, download_dir):
""" Check download_dir for previously downloaded file with correct hash
If a correct file is found return its path else None
"""
download_path = os.path.join(download_dir, link.filename)
if os.path.exists(download_path):
# If already downloaded, does its hash match?
logger.info('File was already downloaded %s', download_path)
if link.hash:
download_hash = _get_hash_from_file(download_path, link)
try:
_check_hash(download_hash, link)
except HashMismatch:
logger.warning(
'Previously-downloaded file %s has bad hash, '
're-downloading.',
download_path
)
os.unlink(download_path)
return None
return download_path
return None