Edit File: configuration.py
"""Configuration management setup Some terminology: - name As written in config files. - value Value associated with a name - key Name combined with it's section (section.name) - variant A single word describing where the configuration key-value pair came from """ import configparser import locale import os import sys from typing import Any, Dict, Iterable, List, NewType, Optional, Tuple from pip._internal.exceptions import ( ConfigurationError, ConfigurationFileCouldNotBeLoaded, ) from pip._internal.utils import appdirs from pip._internal.utils.compat import WINDOWS from pip._internal.utils.logging import getLogger from pip._internal.utils.misc import ensure_dir, enum RawConfigParser = configparser.RawConfigParser # Shorthand Kind = NewType("Kind", str) CONFIG_BASENAME = "pip.ini" if WINDOWS else "pip.conf" ENV_NAMES_IGNORED = "version", "help" # The kinds of configurations there are. kinds = enum( USER="user", # User Specific GLOBAL="global", # System Wide SITE="site", # [Virtual] Environment Specific ENV="env", # from PIP_CONFIG_FILE ENV_VAR="env-var", # from Environment Variables ) OVERRIDE_ORDER = kinds.GLOBAL, kinds.USER, kinds.SITE, kinds.ENV, kinds.ENV_VAR VALID_LOAD_ONLY = kinds.USER, kinds.GLOBAL, kinds.SITE logger = getLogger(__name__) # NOTE: Maybe use the optionx attribute to normalize keynames. def _normalize_name(name: str) -> str: """Make a name consistent regardless of source (environment or file)""" name = name.lower().replace("_", "-") if name.startswith("--"): name = name[2:] # only prefer long opts return name def _disassemble_key(name: str) -> List[str]: if "." not in name: error_message = ( "Key does not contain dot separated section and key. " f"Perhaps you wanted to use 'global.{name}' instead?" ) raise ConfigurationError(error_message) return name.split(".", 1) def get_configuration_files() -> Dict[Kind, List[str]]: global_config_files = [ os.path.join(path, CONFIG_BASENAME) for path in appdirs.site_config_dirs("pip") ] site_config_file = os.path.join(sys.prefix, CONFIG_BASENAME) legacy_config_file = os.path.join( os.path.expanduser("~"), "pip" if WINDOWS else ".pip", CONFIG_BASENAME, ) new_config_file = os.path.join(appdirs.user_config_dir("pip"), CONFIG_BASENAME) return { kinds.GLOBAL: global_config_files, kinds.SITE: [site_config_file], kinds.USER: [legacy_config_file, new_config_file], } class Configuration: """Handles management of configuration. Provides an interface to accessing and managing configuration files. This class converts provides an API that takes "section.key-name" style keys and stores the value associated with it as "key-name" under the section "section". This allows for a clean interface wherein the both the section and the key-name are preserved in an easy to manage form in the configuration files and the data stored is also nice. """ def __init__(self, isolated: bool, load_only: Optional[Kind] = None) -> None: super().__init__() if load_only is not None and load_only not in VALID_LOAD_ONLY: raise ConfigurationError( "Got invalid value for load_only - should be one of {}".format( ", ".join(map(repr, VALID_LOAD_ONLY)) ) ) self.isolated = isolated self.load_only = load_only # Because we keep track of where we got the data from self._parsers: Dict[Kind, List[Tuple[str, RawConfigParser]]] = { variant: [] for variant in OVERRIDE_ORDER } self._config: Dict[Kind, Dict[str, Any]] = { variant: {} for variant in OVERRIDE_ORDER } self._modified_parsers: List[Tuple[str, RawConfigParser]] = [] def load(self) -> None: """Loads configuration from configuration files and environment""" self._load_config_files() if not self.isolated: self._load_environment_vars() def get_file_to_edit(self) -> Optional[str]: """Returns the file with highest priority in configuration""" assert self.load_only is not None, "Need to be specified a file to be editing" try: return self._get_parser_to_modify()[0] except IndexError: return None def items(self) -> Iterable[Tuple[str, Any]]: """Returns key-value pairs like dict.items() representing the loaded configuration """ return self._dictionary.items() def get_value(self, key: str) -> Any: """Get a value from the configuration.""" orig_key = key key = _normalize_name(key) try: return self._dictionary[key] except KeyError: # disassembling triggers a more useful error message than simply # "No such key" in the case that the key isn't in the form command.option _disassemble_key(key) raise ConfigurationError(f"No such key - {orig_key}") def set_value(self, key: str, value: Any) -> None: """Modify a value in the configuration.""" key = _normalize_name(key) self._ensure_have_load_only() assert self.load_only fname, parser = self._get_parser_to_modify() if parser is not None: section, name = _disassemble_key(key) # Modify the parser and the configuration if not parser.has_section(section): parser.add_section(section) parser.set(section, name, value) self._config[self.load_only][key] = value self._mark_as_modified(fname, parser) def unset_value(self, key: str) -> None: """Unset a value in the configuration.""" orig_key = key key = _normalize_name(key) self._ensure_have_load_only() assert self.load_only if key not in self._config[self.load_only]: raise ConfigurationError(f"No such key - {orig_key}") fname, parser = self._get_parser_to_modify() if parser is not None: section, name = _disassemble_key(key) if not ( parser.has_section(section) and parser.remove_option(section, name) ): # The option was not removed. raise ConfigurationError( "Fatal Internal error [id=1]. Please report as a bug." ) # The section may be empty after the option was removed. if not parser.items(section): parser.remove_section(section) self._mark_as_modified(fname, parser) del self._config[self.load_only][key] def save(self) -> None: """Save the current in-memory state.""" self._ensure_have_load_only() for fname, parser in self._modified_parsers: logger.info("Writing to %s", fname) # Ensure directory exists. ensure_dir(os.path.dirname(fname)) # Ensure directory's permission(need to be writeable) try: with open(fname, "w") as f: parser.write(f) except OSError as error: raise ConfigurationError( f"An error occurred while writing to the configuration file " f"{fname}: {error}" ) # # Private routines # def _ensure_have_load_only(self) -> None: if self.load_only is None: raise ConfigurationError("Needed a specific file to be modifying.") logger.debug("Will be working with %s variant only", self.load_only) @property def _dictionary(self) -> Dict[str, Any]: """A dictionary representing the loaded configuration.""" # NOTE: Dictionaries are not populated if not loaded. So, conditionals # are not needed here. retval = {} for variant in OVERRIDE_ORDER: retval.update(self._config[variant]) return retval def _load_config_files(self) -> None: """Loads configuration from configuration files""" config_files = dict(self.iter_config_files()) if config_files[kinds.ENV][0:1] == [os.devnull]: logger.debug( "Skipping loading configuration files due to " "environment's PIP_CONFIG_FILE being os.devnull" ) return for variant, files in config_files.items(): for fname in files: # If there's specific variant set in `load_only`, load only # that variant, not the others. if self.load_only is not None and variant != self.load_only: logger.debug("Skipping file '%s' (variant: %s)", fname, variant) continue parser = self._load_file(variant, fname) # Keeping track of the parsers used self._parsers[variant].append((fname, parser)) def _load_file(self, variant: Kind, fname: str) -> RawConfigParser: logger.verbose("For variant '%s', will try loading '%s'", variant, fname) parser = self._construct_parser(fname) for section in parser.sections(): items = parser.items(section) self._config[variant].update(self._normalized_keys(section, items)) return parser def _construct_parser(self, fname: str) -> RawConfigParser: parser = configparser.RawConfigParser() # If there is no such file, don't bother reading it but create the # parser anyway, to hold the data. # Doing this is useful when modifying and saving files, where we don't # need to construct a parser. if os.path.exists(fname): locale_encoding = locale.getpreferredencoding(False) try: parser.read(fname, encoding=locale_encoding) except UnicodeDecodeError: # See https://github.com/pypa/pip/issues/4963 raise ConfigurationFileCouldNotBeLoaded( reason=f"contains invalid {locale_encoding} characters", fname=fname, ) except configparser.Error as error: # See https://github.com/pypa/pip/issues/4893 raise ConfigurationFileCouldNotBeLoaded(error=error) return parser def _load_environment_vars(self) -> None: """Loads configuration from environment variables""" self._config[kinds.ENV_VAR].update( self._normalized_keys(":env:", self.get_environ_vars()) ) def _normalized_keys( self, section: str, items: Iterable[Tuple[str, Any]] ) -> Dict[str, Any]: """Normalizes items to construct a dictionary with normalized keys. This routine is where the names become keys and are made the same regardless of source - configuration files or environment. """ normalized = {} for name, val in items: key = section + "." + _normalize_name(name) normalized[key] = val return normalized def get_environ_vars(self) -> Iterable[Tuple[str, str]]: """Returns a generator with all environmental vars with prefix PIP_""" for key, val in os.environ.items(): if key.startswith("PIP_"): name = key[4:].lower() if name not in ENV_NAMES_IGNORED: yield name, val # XXX: This is patched in the tests. def iter_config_files(self) -> Iterable[Tuple[Kind, List[str]]]: """Yields variant and configuration files associated with it. This should be treated like items of a dictionary. The order here doesn't affect what gets overridden. That is controlled by OVERRIDE_ORDER. However this does control the order they are displayed to the user. It's probably most ergonomic to display things in the same order as OVERRIDE_ORDER """ # SMELL: Move the conditions out of this function env_config_file = os.environ.get("PIP_CONFIG_FILE", None) config_files = get_configuration_files() yield kinds.GLOBAL, config_files[kinds.GLOBAL] # per-user config is not loaded when env_config_file exists should_load_user_config = not self.isolated and not ( env_config_file and os.path.exists(env_config_file) ) if should_load_user_config: # The legacy config file is overridden by the new config file yield kinds.USER, config_files[kinds.USER] # virtualenv config yield kinds.SITE, config_files[kinds.SITE] if env_config_file is not None: yield kinds.ENV, [env_config_file] else: yield kinds.ENV, [] def get_values_in_config(self, variant: Kind) -> Dict[str, Any]: """Get values present in a config file""" return self._config[variant] def _get_parser_to_modify(self) -> Tuple[str, RawConfigParser]: # Determine which parser to modify assert self.load_only parsers = self._parsers[self.load_only] if not parsers: # This should not happen if everything works correctly. raise ConfigurationError( "Fatal Internal error [id=2]. Please report as a bug." ) # Use the highest priority parser. return parsers[-1] # XXX: This is patched in the tests. def _mark_as_modified(self, fname: str, parser: RawConfigParser) -> None: file_parser_tuple = (fname, parser) if file_parser_tuple not in self._modified_parsers: self._modified_parsers.append(file_parser_tuple) def __repr__(self) -> str: return f"{self.__class__.__name__}({self._dictionary!r})"