545 lines
17 KiB
Python
545 lines
17 KiB
Python
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"""
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Requirements file parsing
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"""
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import optparse
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import os
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import re
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import shlex
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import urllib.parse
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from optparse import Values
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from typing import (
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TYPE_CHECKING,
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Any,
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Callable,
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Dict,
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Generator,
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Iterable,
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List,
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Optional,
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Tuple,
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)
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from pip._internal.cli import cmdoptions
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from pip._internal.exceptions import InstallationError, RequirementsFileParseError
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from pip._internal.models.search_scope import SearchScope
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from pip._internal.network.session import PipSession
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from pip._internal.network.utils import raise_for_status
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from pip._internal.utils.encoding import auto_decode
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from pip._internal.utils.urls import get_url_scheme
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if TYPE_CHECKING:
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# NoReturn introduced in 3.6.2; imported only for type checking to maintain
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# pip compatibility with older patch versions of Python 3.6
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from typing import NoReturn
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from pip._internal.index.package_finder import PackageFinder
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__all__ = ["parse_requirements"]
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ReqFileLines = Iterable[Tuple[int, str]]
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LineParser = Callable[[str], Tuple[str, Values]]
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SCHEME_RE = re.compile(r"^(http|https|file):", re.I)
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COMMENT_RE = re.compile(r"(^|\s+)#.*$")
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# Matches environment variable-style values in '${MY_VARIABLE_1}' with the
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# variable name consisting of only uppercase letters, digits or the '_'
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# (underscore). This follows the POSIX standard defined in IEEE Std 1003.1,
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# 2013 Edition.
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ENV_VAR_RE = re.compile(r"(?P<var>\$\{(?P<name>[A-Z0-9_]+)\})")
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SUPPORTED_OPTIONS: List[Callable[..., optparse.Option]] = [
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cmdoptions.index_url,
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cmdoptions.extra_index_url,
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cmdoptions.no_index,
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cmdoptions.constraints,
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cmdoptions.requirements,
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cmdoptions.editable,
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cmdoptions.find_links,
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cmdoptions.no_binary,
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cmdoptions.only_binary,
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cmdoptions.prefer_binary,
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cmdoptions.require_hashes,
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cmdoptions.pre,
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cmdoptions.trusted_host,
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cmdoptions.use_new_feature,
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]
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# options to be passed to requirements
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SUPPORTED_OPTIONS_REQ: List[Callable[..., optparse.Option]] = [
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cmdoptions.install_options,
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cmdoptions.global_options,
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cmdoptions.hash,
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]
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# the 'dest' string values
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SUPPORTED_OPTIONS_REQ_DEST = [str(o().dest) for o in SUPPORTED_OPTIONS_REQ]
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class ParsedRequirement:
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def __init__(
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self,
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requirement: str,
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is_editable: bool,
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comes_from: str,
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constraint: bool,
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options: Optional[Dict[str, Any]] = None,
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line_source: Optional[str] = None,
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) -> None:
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self.requirement = requirement
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self.is_editable = is_editable
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self.comes_from = comes_from
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self.options = options
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self.constraint = constraint
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self.line_source = line_source
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class ParsedLine:
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def __init__(
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self,
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filename: str,
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lineno: int,
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args: str,
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opts: Values,
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constraint: bool,
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) -> None:
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self.filename = filename
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self.lineno = lineno
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self.opts = opts
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self.constraint = constraint
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if args:
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self.is_requirement = True
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self.is_editable = False
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self.requirement = args
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elif opts.editables:
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self.is_requirement = True
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self.is_editable = True
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# We don't support multiple -e on one line
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self.requirement = opts.editables[0]
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else:
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self.is_requirement = False
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def parse_requirements(
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filename: str,
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session: PipSession,
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finder: Optional["PackageFinder"] = None,
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options: Optional[optparse.Values] = None,
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constraint: bool = False,
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) -> Generator[ParsedRequirement, None, None]:
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"""Parse a requirements file and yield ParsedRequirement instances.
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:param filename: Path or url of requirements file.
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:param session: PipSession instance.
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:param finder: Instance of pip.index.PackageFinder.
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:param options: cli options.
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:param constraint: If true, parsing a constraint file rather than
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requirements file.
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"""
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line_parser = get_line_parser(finder)
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parser = RequirementsFileParser(session, line_parser)
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for parsed_line in parser.parse(filename, constraint):
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parsed_req = handle_line(
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parsed_line, options=options, finder=finder, session=session
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)
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if parsed_req is not None:
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yield parsed_req
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def preprocess(content: str) -> ReqFileLines:
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"""Split, filter, and join lines, and return a line iterator
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:param content: the content of the requirements file
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"""
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lines_enum: ReqFileLines = enumerate(content.splitlines(), start=1)
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lines_enum = join_lines(lines_enum)
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lines_enum = ignore_comments(lines_enum)
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lines_enum = expand_env_variables(lines_enum)
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return lines_enum
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def handle_requirement_line(
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line: ParsedLine,
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options: Optional[optparse.Values] = None,
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) -> ParsedRequirement:
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# preserve for the nested code path
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line_comes_from = "{} {} (line {})".format(
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"-c" if line.constraint else "-r",
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line.filename,
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line.lineno,
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)
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assert line.is_requirement
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if line.is_editable:
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# For editable requirements, we don't support per-requirement
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# options, so just return the parsed requirement.
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return ParsedRequirement(
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requirement=line.requirement,
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is_editable=line.is_editable,
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comes_from=line_comes_from,
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constraint=line.constraint,
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)
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else:
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# get the options that apply to requirements
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req_options = {}
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for dest in SUPPORTED_OPTIONS_REQ_DEST:
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if dest in line.opts.__dict__ and line.opts.__dict__[dest]:
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req_options[dest] = line.opts.__dict__[dest]
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line_source = f"line {line.lineno} of {line.filename}"
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return ParsedRequirement(
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requirement=line.requirement,
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is_editable=line.is_editable,
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comes_from=line_comes_from,
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constraint=line.constraint,
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options=req_options,
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line_source=line_source,
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)
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def handle_option_line(
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opts: Values,
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filename: str,
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lineno: int,
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finder: Optional["PackageFinder"] = None,
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options: Optional[optparse.Values] = None,
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session: Optional[PipSession] = None,
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) -> None:
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if options:
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# percolate options upward
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if opts.require_hashes:
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options.require_hashes = opts.require_hashes
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if opts.features_enabled:
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options.features_enabled.extend(
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f for f in opts.features_enabled if f not in options.features_enabled
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)
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# set finder options
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if finder:
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find_links = finder.find_links
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index_urls = finder.index_urls
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no_index = finder.search_scope.no_index
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if opts.no_index is True:
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no_index = True
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index_urls = []
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if opts.index_url and not no_index:
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index_urls = [opts.index_url]
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if opts.extra_index_urls and not no_index:
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index_urls.extend(opts.extra_index_urls)
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if opts.find_links:
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# FIXME: it would be nice to keep track of the source
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# of the find_links: support a find-links local path
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# relative to a requirements file.
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value = opts.find_links[0]
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req_dir = os.path.dirname(os.path.abspath(filename))
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relative_to_reqs_file = os.path.join(req_dir, value)
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if os.path.exists(relative_to_reqs_file):
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value = relative_to_reqs_file
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find_links.append(value)
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if session:
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# We need to update the auth urls in session
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session.update_index_urls(index_urls)
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search_scope = SearchScope(
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find_links=find_links,
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index_urls=index_urls,
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no_index=no_index,
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)
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finder.search_scope = search_scope
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if opts.pre:
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finder.set_allow_all_prereleases()
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if opts.prefer_binary:
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finder.set_prefer_binary()
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if session:
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for host in opts.trusted_hosts or []:
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source = f"line {lineno} of {filename}"
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session.add_trusted_host(host, source=source)
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def handle_line(
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line: ParsedLine,
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options: Optional[optparse.Values] = None,
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finder: Optional["PackageFinder"] = None,
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session: Optional[PipSession] = None,
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) -> Optional[ParsedRequirement]:
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"""Handle a single parsed requirements line; This can result in
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creating/yielding requirements, or updating the finder.
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:param line: The parsed line to be processed.
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:param options: CLI options.
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:param finder: The finder - updated by non-requirement lines.
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:param session: The session - updated by non-requirement lines.
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Returns a ParsedRequirement object if the line is a requirement line,
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otherwise returns None.
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For lines that contain requirements, the only options that have an effect
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are from SUPPORTED_OPTIONS_REQ, and they are scoped to the
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requirement. Other options from SUPPORTED_OPTIONS may be present, but are
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ignored.
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For lines that do not contain requirements, the only options that have an
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effect are from SUPPORTED_OPTIONS. Options from SUPPORTED_OPTIONS_REQ may
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be present, but are ignored. These lines may contain multiple options
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(although our docs imply only one is supported), and all our parsed and
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affect the finder.
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"""
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if line.is_requirement:
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parsed_req = handle_requirement_line(line, options)
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return parsed_req
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else:
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handle_option_line(
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line.opts,
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line.filename,
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line.lineno,
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finder,
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options,
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session,
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)
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return None
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class RequirementsFileParser:
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def __init__(
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self,
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session: PipSession,
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line_parser: LineParser,
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) -> None:
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self._session = session
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self._line_parser = line_parser
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def parse(
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self, filename: str, constraint: bool
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) -> Generator[ParsedLine, None, None]:
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"""Parse a given file, yielding parsed lines."""
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yield from self._parse_and_recurse(filename, constraint)
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def _parse_and_recurse(
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self, filename: str, constraint: bool
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) -> Generator[ParsedLine, None, None]:
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for line in self._parse_file(filename, constraint):
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if not line.is_requirement and (
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line.opts.requirements or line.opts.constraints
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):
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# parse a nested requirements file
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if line.opts.requirements:
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req_path = line.opts.requirements[0]
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nested_constraint = False
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else:
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req_path = line.opts.constraints[0]
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nested_constraint = True
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# original file is over http
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if SCHEME_RE.search(filename):
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# do a url join so relative paths work
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req_path = urllib.parse.urljoin(filename, req_path)
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# original file and nested file are paths
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elif not SCHEME_RE.search(req_path):
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# do a join so relative paths work
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req_path = os.path.join(
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os.path.dirname(filename),
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req_path,
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)
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yield from self._parse_and_recurse(req_path, nested_constraint)
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else:
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yield line
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def _parse_file(
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self, filename: str, constraint: bool
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) -> Generator[ParsedLine, None, None]:
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_, content = get_file_content(filename, self._session)
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lines_enum = preprocess(content)
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for line_number, line in lines_enum:
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try:
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args_str, opts = self._line_parser(line)
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except OptionParsingError as e:
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# add offending line
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msg = f"Invalid requirement: {line}\n{e.msg}"
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raise RequirementsFileParseError(msg)
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yield ParsedLine(
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filename,
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line_number,
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args_str,
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opts,
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constraint,
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)
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def get_line_parser(finder: Optional["PackageFinder"]) -> LineParser:
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|
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def parse_line(line: str) -> Tuple[str, Values]:
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|
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# Build new parser for each line since it accumulates appendable
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# options.
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parser = build_parser()
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defaults = parser.get_default_values()
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defaults.index_url = None
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||
|
|
if finder:
|
||
|
|
defaults.format_control = finder.format_control
|
||
|
|
|
||
|
|
args_str, options_str = break_args_options(line)
|
||
|
|
|
||
|
|
try:
|
||
|
|
options = shlex.split(options_str)
|
||
|
|
except ValueError as e:
|
||
|
|
raise OptionParsingError(f"Could not split options: {options_str}") from e
|
||
|
|
|
||
|
|
opts, _ = parser.parse_args(options, defaults)
|
||
|
|
|
||
|
|
return args_str, opts
|
||
|
|
|
||
|
|
return parse_line
|
||
|
|
|
||
|
|
|
||
|
|
def break_args_options(line: str) -> Tuple[str, str]:
|
||
|
|
"""Break up the line into an args and options string. We only want to shlex
|
||
|
|
(and then optparse) the options, not the args. args can contain markers
|
||
|
|
which are corrupted by shlex.
|
||
|
|
"""
|
||
|
|
tokens = line.split(" ")
|
||
|
|
args = []
|
||
|
|
options = tokens[:]
|
||
|
|
for token in tokens:
|
||
|
|
if token.startswith("-") or token.startswith("--"):
|
||
|
|
break
|
||
|
|
else:
|
||
|
|
args.append(token)
|
||
|
|
options.pop(0)
|
||
|
|
return " ".join(args), " ".join(options)
|
||
|
|
|
||
|
|
|
||
|
|
class OptionParsingError(Exception):
|
||
|
|
def __init__(self, msg: str) -> None:
|
||
|
|
self.msg = msg
|
||
|
|
|
||
|
|
|
||
|
|
def build_parser() -> optparse.OptionParser:
|
||
|
|
"""
|
||
|
|
Return a parser for parsing requirement lines
|
||
|
|
"""
|
||
|
|
parser = optparse.OptionParser(add_help_option=False)
|
||
|
|
|
||
|
|
option_factories = SUPPORTED_OPTIONS + SUPPORTED_OPTIONS_REQ
|
||
|
|
for option_factory in option_factories:
|
||
|
|
option = option_factory()
|
||
|
|
parser.add_option(option)
|
||
|
|
|
||
|
|
# By default optparse sys.exits on parsing errors. We want to wrap
|
||
|
|
# that in our own exception.
|
||
|
|
def parser_exit(self: Any, msg: str) -> "NoReturn":
|
||
|
|
raise OptionParsingError(msg)
|
||
|
|
|
||
|
|
# NOTE: mypy disallows assigning to a method
|
||
|
|
# https://github.com/python/mypy/issues/2427
|
||
|
|
parser.exit = parser_exit # type: ignore
|
||
|
|
|
||
|
|
return parser
|
||
|
|
|
||
|
|
|
||
|
|
def join_lines(lines_enum: ReqFileLines) -> ReqFileLines:
|
||
|
|
"""Joins a line ending in '\' with the previous line (except when following
|
||
|
|
comments). The joined line takes on the index of the first line.
|
||
|
|
"""
|
||
|
|
primary_line_number = None
|
||
|
|
new_line: List[str] = []
|
||
|
|
for line_number, line in lines_enum:
|
||
|
|
if not line.endswith("\\") or COMMENT_RE.match(line):
|
||
|
|
if COMMENT_RE.match(line):
|
||
|
|
# this ensures comments are always matched later
|
||
|
|
line = " " + line
|
||
|
|
if new_line:
|
||
|
|
new_line.append(line)
|
||
|
|
assert primary_line_number is not None
|
||
|
|
yield primary_line_number, "".join(new_line)
|
||
|
|
new_line = []
|
||
|
|
else:
|
||
|
|
yield line_number, line
|
||
|
|
else:
|
||
|
|
if not new_line:
|
||
|
|
primary_line_number = line_number
|
||
|
|
new_line.append(line.strip("\\"))
|
||
|
|
|
||
|
|
# last line contains \
|
||
|
|
if new_line:
|
||
|
|
assert primary_line_number is not None
|
||
|
|
yield primary_line_number, "".join(new_line)
|
||
|
|
|
||
|
|
# TODO: handle space after '\'.
|
||
|
|
|
||
|
|
|
||
|
|
def ignore_comments(lines_enum: ReqFileLines) -> ReqFileLines:
|
||
|
|
"""
|
||
|
|
Strips comments and filter empty lines.
|
||
|
|
"""
|
||
|
|
for line_number, line in lines_enum:
|
||
|
|
line = COMMENT_RE.sub("", line)
|
||
|
|
line = line.strip()
|
||
|
|
if line:
|
||
|
|
yield line_number, line
|
||
|
|
|
||
|
|
|
||
|
|
def expand_env_variables(lines_enum: ReqFileLines) -> ReqFileLines:
|
||
|
|
"""Replace all environment variables that can be retrieved via `os.getenv`.
|
||
|
|
|
||
|
|
The only allowed format for environment variables defined in the
|
||
|
|
requirement file is `${MY_VARIABLE_1}` to ensure two things:
|
||
|
|
|
||
|
|
1. Strings that contain a `$` aren't accidentally (partially) expanded.
|
||
|
|
2. Ensure consistency across platforms for requirement files.
|
||
|
|
|
||
|
|
These points are the result of a discussion on the `github pull
|
||
|
|
request #3514 <https://github.com/pypa/pip/pull/3514>`_.
|
||
|
|
|
||
|
|
Valid characters in variable names follow the `POSIX standard
|
||
|
|
<http://pubs.opengroup.org/onlinepubs/9699919799/>`_ and are limited
|
||
|
|
to uppercase letter, digits and the `_` (underscore).
|
||
|
|
"""
|
||
|
|
for line_number, line in lines_enum:
|
||
|
|
for env_var, var_name in ENV_VAR_RE.findall(line):
|
||
|
|
value = os.getenv(var_name)
|
||
|
|
if not value:
|
||
|
|
continue
|
||
|
|
|
||
|
|
line = line.replace(env_var, value)
|
||
|
|
|
||
|
|
yield line_number, line
|
||
|
|
|
||
|
|
|
||
|
|
def get_file_content(url: str, session: PipSession) -> Tuple[str, str]:
|
||
|
|
"""Gets the content of a file; it may be a filename, file: URL, or
|
||
|
|
http: URL. Returns (location, content). Content is unicode.
|
||
|
|
Respects # -*- coding: declarations on the retrieved files.
|
||
|
|
|
||
|
|
:param url: File path or url.
|
||
|
|
:param session: PipSession instance.
|
||
|
|
"""
|
||
|
|
scheme = get_url_scheme(url)
|
||
|
|
|
||
|
|
# Pip has special support for file:// URLs (LocalFSAdapter).
|
||
|
|
if scheme in ["http", "https", "file"]:
|
||
|
|
resp = session.get(url)
|
||
|
|
raise_for_status(resp)
|
||
|
|
return resp.url, resp.text
|
||
|
|
|
||
|
|
# Assume this is a bare path.
|
||
|
|
try:
|
||
|
|
with open(url, "rb") as f:
|
||
|
|
content = auto_decode(f.read())
|
||
|
|
except OSError as exc:
|
||
|
|
raise InstallationError(f"Could not open requirements file: {exc}")
|
||
|
|
return url, content
|