""" Requirements file parsing """ import codecs import locale import logging import optparse import os import re import shlex import sys import urllib.parse from dataclasses import dataclass from optparse import Values from typing import ( TYPE_CHECKING, Any, Callable, Dict, Generator, Iterable, List, NoReturn, Optional, Tuple, ) from pip._internal.cli import cmdoptions from pip._internal.exceptions import InstallationError, RequirementsFileParseError from pip._internal.models.search_scope import SearchScope if TYPE_CHECKING: from pip._internal.index.package_finder import PackageFinder from pip._internal.network.session import PipSession __all__ = ["parse_requirements"] ReqFileLines = Iterable[Tuple[int, str]] LineParser = Callable[[str], Tuple[str, Values]] SCHEME_RE = re.compile(r"^(http|https|file):", re.I) COMMENT_RE = re.compile(r"(^|\s+)#.*$") # Matches environment variable-style values in '${MY_VARIABLE_1}' with the # variable name consisting of only uppercase letters, digits or the '_' # (underscore). This follows the POSIX standard defined in IEEE Std 1003.1, # 2013 Edition. ENV_VAR_RE = re.compile(r"(?P<var>\$\{(?P<name>[A-Z0-9_]+)\})") SUPPORTED_OPTIONS: List[Callable[..., optparse.Option]] = [ cmdoptions.index_url, cmdoptions.extra_index_url, cmdoptions.no_index, cmdoptions.constraints, cmdoptions.requirements, cmdoptions.editable, cmdoptions.find_links, cmdoptions.no_binary, cmdoptions.only_binary, cmdoptions.prefer_binary, cmdoptions.require_hashes, cmdoptions.pre, cmdoptions.trusted_host, cmdoptions.use_new_feature, ] # options to be passed to requirements SUPPORTED_OPTIONS_REQ: List[Callable[..., optparse.Option]] = [ cmdoptions.global_options, cmdoptions.hash, cmdoptions.config_settings, ] SUPPORTED_OPTIONS_EDITABLE_REQ: List[Callable[..., optparse.Option]] = [ cmdoptions.config_settings, ] # the 'dest' string values SUPPORTED_OPTIONS_REQ_DEST = [str(o().dest) for o in SUPPORTED_OPTIONS_REQ] SUPPORTED_OPTIONS_EDITABLE_REQ_DEST = [ str(o().dest) for o in SUPPORTED_OPTIONS_EDITABLE_REQ ] # order of BOMS is important: codecs.BOM_UTF16_LE is a prefix of codecs.BOM_UTF32_LE # so data.startswith(BOM_UTF16_LE) would be true for UTF32_LE data BOMS: List[Tuple[bytes, str]] = [ (codecs.BOM_UTF8, "utf-8"), (codecs.BOM_UTF32, "utf-32"), (codecs.BOM_UTF32_BE, "utf-32-be"), (codecs.BOM_UTF32_LE, "utf-32-le"), (codecs.BOM_UTF16, "utf-16"), (codecs.BOM_UTF16_BE, "utf-16-be"), (codecs.BOM_UTF16_LE, "utf-16-le"), ] PEP263_ENCODING_RE = re.compile(rb"coding[:=]\s*([-\w.]+)") DEFAULT_ENCODING = "utf-8" logger = logging.getLogger(__name__) @dataclass(frozen=True) class ParsedRequirement: # TODO: replace this with slots=True when dropping Python 3.9 support. __slots__ = ( "requirement", "is_editable", "comes_from", "constraint", "options", "line_source", ) requirement: str is_editable: bool comes_from: str constraint: bool options: Optional[Dict[str, Any]] line_source: Optional[str] @dataclass(frozen=True) class ParsedLine: __slots__ = ("filename", "lineno", "args", "opts", "constraint") filename: str lineno: int args: str opts: Values constraint: bool @property def is_editable(self) -> bool: return bool(self.opts.editables) @property def requirement(self) -> Optional[str]: if self.args: return self.args elif self.is_editable: # We don't support multiple -e on one line return self.opts.editables[0] return None def parse_requirements( filename: str, session: "PipSession", finder: Optional["PackageFinder"] = None, options: Optional[optparse.Values] = None, constraint: bool = False, ) -> Generator[ParsedRequirement, None, None]: """Parse a requirements file and yield ParsedRequirement instances. :param filename: Path or url of requirements file. :param session: PipSession instance. :param finder: Instance of pip.index.PackageFinder. :param options: cli options. :param constraint: If true, parsing a constraint file rather than requirements file. """ line_parser = get_line_parser(finder) parser = RequirementsFileParser(session, line_parser) for parsed_line in parser.parse(filename, constraint): parsed_req = handle_line( parsed_line, options=options, finder=finder, session=session ) if parsed_req is not None: yield parsed_req def preprocess(content: str) -> ReqFileLines: """Split, filter, and join lines, and return a line iterator :param content: the content of the requirements file """ lines_enum: ReqFileLines = enumerate(content.splitlines(), start=1) lines_enum = join_lines(lines_enum) lines_enum = ignore_comments(lines_enum) lines_enum = expand_env_variables(lines_enum) return lines_enum def handle_requirement_line( line: ParsedLine, options: Optional[optparse.Values] = None, ) -> ParsedRequirement: # preserve for the nested code path line_comes_from = "{} {} (line {})".format( "-c" if line.constraint else "-r", line.filename, line.lineno, ) assert line.requirement is not None # get the options that apply to requirements if line.is_editable: supported_dest = SUPPORTED_OPTIONS_EDITABLE_REQ_DEST else: supported_dest = SUPPORTED_OPTIONS_REQ_DEST req_options = {} for dest in supported_dest: if dest in line.opts.__dict__ and line.opts.__dict__[dest]: req_options[dest] = line.opts.__dict__[dest] line_source = f"line {line.lineno} of {line.filename}" return ParsedRequirement( requirement=line.requirement, is_editable=line.is_editable, comes_from=line_comes_from, constraint=line.constraint, options=req_options, line_source=line_source, ) def handle_option_line( opts: Values, filename: str, lineno: int, finder: Optional["PackageFinder"] = None, options: Optional[optparse.Values] = None, session: Optional["PipSession"] = None, ) -> None: if opts.hashes: logger.warning( "%s line %s has --hash but no requirement, and will be ignored.", filename, lineno, ) if options: # percolate options upward if opts.require_hashes: options.require_hashes = opts.require_hashes if opts.features_enabled: options.features_enabled.extend( f for f in opts.features_enabled if f not in options.features_enabled ) # set finder options if finder: find_links = finder.find_links index_urls = finder.index_urls no_index = finder.search_scope.no_index if opts.no_index is True: no_index = True index_urls = [] if opts.index_url and not no_index: index_urls = [opts.index_url] if opts.extra_index_urls and not no_index: index_urls.extend(opts.extra_index_urls) if opts.find_links: # FIXME: it would be nice to keep track of the source # of the find_links: support a find-links local path # relative to a requirements file. value = opts.find_links[0] req_dir = os.path.dirname(os.path.abspath(filename)) relative_to_reqs_file = os.path.join(req_dir, value) if os.path.exists(relative_to_reqs_file): value = relative_to_reqs_file find_links.append(value) if session: # We need to update the auth urls in session session.update_index_urls(index_urls) search_scope = SearchScope( find_links=find_links, index_urls=index_urls, no_index=no_index, ) finder.search_scope = search_scope if opts.pre: finder.set_allow_all_prereleases() if opts.prefer_binary: finder.set_prefer_binary() if session: for host in opts.trusted_hosts or []: source = f"line {lineno} of {filename}" session.add_trusted_host(host, source=source) def handle_line( line: ParsedLine, options: Optional[optparse.Values] = None, finder: Optional["PackageFinder"] = None, session: Optional["PipSession"] = None, ) -> Optional[ParsedRequirement]: """Handle a single parsed requirements line; This can result in creating/yielding requirements, or updating the finder. :param line: The parsed line to be processed. :param options: CLI options. :param finder: The finder - updated by non-requirement lines. :param session: The session - updated by non-requirement lines. Returns a ParsedRequirement object if the line is a requirement line, otherwise returns None. For lines that contain requirements, the only options that have an effect are from SUPPORTED_OPTIONS_REQ, and they are scoped to the requirement. Other options from SUPPORTED_OPTIONS may be present, but are ignored. For lines that do not contain requirements, the only options that have an effect are from SUPPORTED_OPTIONS. Options from SUPPORTED_OPTIONS_REQ may be present, but are ignored. These lines may contain multiple options (although our docs imply only one is supported), and all our parsed and affect the finder. """ if line.requirement is not None: parsed_req = handle_requirement_line(line, options) return parsed_req else: handle_option_line( line.opts, line.filename, line.lineno, finder, options, session, ) return None class RequirementsFileParser: def __init__( self, session: "PipSession", line_parser: LineParser, ) -> None: self._session = session self._line_parser = line_parser def parse( self, filename: str, constraint: bool ) -> Generator[ParsedLine, None, None]: """Parse a given file, yielding parsed lines.""" yield from self._parse_and_recurse( filename, constraint, [{os.path.abspath(filename): None}] ) def _parse_and_recurse( self, filename: str, constraint: bool, parsed_files_stack: List[Dict[str, Optional[str]]], ) -> Generator[ParsedLine, None, None]: for line in self._parse_file(filename, constraint): if line.requirement is None and ( line.opts.requirements or line.opts.constraints ): # parse a nested requirements file if line.opts.requirements: req_path = line.opts.requirements[0] nested_constraint = False else: req_path = line.opts.constraints[0] nested_constraint = True # original file is over http if SCHEME_RE.search(filename): # do a url join so relative paths work req_path = urllib.parse.urljoin(filename, req_path) # original file and nested file are paths elif not SCHEME_RE.search(req_path): # do a join so relative paths work # and then abspath so that we can identify recursive references req_path = os.path.abspath( os.path.join( os.path.dirname(filename), req_path, ) ) parsed_files = parsed_files_stack[0] if req_path in parsed_files: initial_file = parsed_files[req_path] tail = ( f" and again in {initial_file}" if initial_file is not None else "" ) raise RequirementsFileParseError( f"{req_path} recursively references itself in {filename}{tail}" ) # Keeping a track where was each file first included in new_parsed_files = parsed_files.copy() new_parsed_files[req_path] = filename yield from self._parse_and_recurse( req_path, nested_constraint, [new_parsed_files, *parsed_files_stack] ) else: yield line def _parse_file( self, filename: str, constraint: bool ) -> Generator[ParsedLine, None, None]: _, content = get_file_content(filename, self._session) lines_enum = preprocess(content) for line_number, line in lines_enum: try: args_str, opts = self._line_parser(line) except OptionParsingError as e: # add offending line msg = f"Invalid requirement: {line}\n{e.msg}" raise RequirementsFileParseError(msg) yield ParsedLine( filename, line_number, args_str, opts, constraint, ) def get_line_parser(finder: Optional["PackageFinder"]) -> LineParser: def parse_line(line: str) -> Tuple[str, Values]: # Build new parser for each line since it accumulates appendable # options. parser = build_parser() defaults = parser.get_default_values() defaults.index_url = None 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 = urllib.parse.urlsplit(url).scheme # Pip has special support for file:// URLs (LocalFSAdapter). if scheme in ["http", "https", "file"]: # Delay importing heavy network modules until absolutely necessary. from pip._internal.network.utils import raise_for_status 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: raw_content = f.read() except OSError as exc: raise InstallationError(f"Could not open requirements file: {exc}") content = _decode_req_file(raw_content, url) return url, content def _decode_req_file(data: bytes, url: str) -> str: for bom, encoding in BOMS: if data.startswith(bom): return data[len(bom) :].decode(encoding) for line in data.split(b"\n")[:2]: if line[0:1] == b"#": result = PEP263_ENCODING_RE.search(line) if result is not None: encoding = result.groups()[0].decode("ascii") return data.decode(encoding) try: return data.decode(DEFAULT_ENCODING) except UnicodeDecodeError: locale_encoding = locale.getpreferredencoding(False) or sys.getdefaultencoding() logging.warning( "unable to decode data from %s with default encoding %s, " "falling back to encoding from locale: %s. " "If this is intentional you should specify the encoding with a " "PEP-263 style comment, e.g. '# -*- coding: %s -*-'", url, DEFAULT_ENCODING, locale_encoding, locale_encoding, ) return data.decode(locale_encoding)