Source code for click_extra.config

# Copyright Kevin Deldycke <kevin@deldycke.com> and contributors.
#
# This program is Free Software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
"""Utilities to load parameters and options from a configuration file."""

from __future__ import annotations

import logging
import json
import os
import sys
from configparser import ConfigParser, ExtendedInterpolation
from enum import Enum
from gettext import gettext as _
from pathlib import Path
from typing import Any, Iterable, Sequence
from unittest.mock import patch

if sys.version_info >= (3, 11):
    import tomllib
else:
    import tomli as tomllib  # type: ignore[import-not-found]

import requests
import xmltodict
import yaml
from boltons.iterutils import flatten
from boltons.pathutils import shrinkuser
from boltons.urlutils import URL
from extra_platforms import is_windows
from extra_platforms.platform import _recursive_update, _remove_blanks
from mergedeep import merge
from wcmatch.glob import (
    BRACE,
    DOTGLOB,
    FOLLOW,
    GLOBSTAR,
    GLOBTILDE,
    IGNORECASE,
    NODIR,
    iglob,
)

from . import (
    STRING,
    Context,
    Parameter,
    ParameterSource,
    echo,
    get_app_dir,
    get_current_context,
)
from .parameters import ExtraOption, ParamStructure


[docs] class Formats(Enum): """Supported configuration formats and the list of their default extensions. The default order set the priority by which each format is searched for the default configuration file. """ TOML = ("toml",) YAML = ("yaml", "yml") JSON = ("json",) INI = ("ini",) XML = ("xml",)
[docs] class ConfigOption(ExtraOption, ParamStructure): """A pre-configured option adding ``--config``/``-C`` option.""" formats: Sequence[Formats] roaming: bool force_posix: bool strict: bool def __init__( self, param_decls: Sequence[str] | None = None, metavar="CONFIG_PATH", type=STRING, help=_( "Location of the configuration file. Supports glob pattern of local " "path and remote URL.", ), is_eager=True, expose_value=False, formats=tuple(Formats), roaming=True, force_posix=False, excluded_params=None, strict=False, **kwargs, ) -> None: """Takes as input a glob pattern or an URL. Glob patterns must follow the syntax of `wcmatch.glob <https://facelessuser.github.io/wcmatch/glob/#syntax>`_. - ``is_eager`` is active by default so the config option's ``callback`` gets the opportunity to set the ``default_map`` values before the other options use them. - ``formats`` is the ordered list of formats that the configuration file will be tried to be read with. Can be a single one. - ``roaming`` and ``force_posix`` are `fed to click.get_app_dir() <https://click.palletsprojects.com/en/stable/api/#click.get_app_dir>`_ to setup the default configuration folder. - ``excluded_params`` is a list of options to ignore by the configuration parser. Defaults to ``ParamStructure.DEFAULT_EXCLUDED_PARAMS``. - ``strict`` - If ``True``, raise an error if the configuration file contain unrecognized content. - If ``False``, silently ignore unsupported configuration option. """ if not param_decls: param_decls = ("--config", "-C") # Make sure formats ends up as an iterable. if isinstance(formats, Formats): formats = (formats,) self.formats = formats # Setup the configuration default folder. self.roaming = roaming self.force_posix = force_posix kwargs.setdefault("default", self.default_pattern) if excluded_params is not None: self.excluded_params = excluded_params self.strict = strict kwargs.setdefault("callback", self.load_conf) super().__init__( param_decls=param_decls, metavar=metavar, type=type, help=help, is_eager=is_eager, expose_value=expose_value, **kwargs, )
[docs] def default_pattern(self) -> str: """Returns the default pattern used to search for the configuration file. Defaults to ``/<app_dir>/*.{toml,yaml,yml,json,ini,xml}``. Where ``<app_dir>`` is produced by the `clickget_app_dir() method <https://click.palletsprojects.com/en/stable/api/#click.get_app_dir>`_. The result depends on OS and is influenced by the ``roaming`` and ``force_posix`` properties of this instance. In that folder, we're looking for any file matching the extensions derived from the ``self.formats`` property: - a simple ``*.ext`` pattern if only one format is set - an expanded ``*.{ext1,ext2,...}`` pattern if multiple formats are set """ ctx = get_current_context() cli_name = ctx.find_root().info_name if not cli_name: raise ValueError app_dir = Path( get_app_dir(cli_name, roaming=self.roaming, force_posix=self.force_posix), ).resolve() # Build the extension matching pattern. extensions = flatten(f.value for f in self.formats) if len(extensions) == 1: ext_pattern = extensions[0] else: # Use brace notation for multiple extension matching. ext_pattern = f"{{{','.join(extensions)}}}" return f"{app_dir}{os.path.sep}*.{ext_pattern}"
[docs] def get_help_record(self, ctx: Context) -> tuple[str, str] | None: """Replaces the default value by the pretty version of the configuration matching pattern.""" # Pre-compute pretty_path to bypass infinite recursive loop on get_default. pretty_path = shrinkuser(Path(self.get_default(ctx))) # type: ignore[arg-type] with patch.object(ConfigOption, "get_default") as mock_method: mock_method.return_value = pretty_path return super().get_help_record(ctx)
[docs] def search_and_read_conf(self, pattern: str) -> Iterable[tuple[Path | URL, str]]: """Search on local file system or remote URL files matching the provided pattern. ``pattern`` is considered an URL only if it is parseable as such and starts with ``http://`` or ``https://``. Returns an iterator of the normalized configuration location and its textual content, for each file/URL matching the pattern. """ logger = logging.getLogger("click_extra") # Check if the pattern is an URL. location = URL(pattern) location.normalize() if location and location.scheme in ("http", "https"): logger.debug(f"Download configuration from URL: {location}") with requests.get(location) as response: if response.ok: yield location, response.text return logger.warning(f"Can't download {location}: {response.reason}") logger.debug("Pattern is not an URL: search local file system.") # wcmatch expect patterns to be written with Unix-like syntax by default, even # on Windows. See more details at: # https://facelessuser.github.io/wcmatch/glob/#windows-separators # https://github.com/facelessuser/wcmatch/issues/194 if is_windows(): pattern = pattern.replace("\\", "/") for file in iglob( pattern, flags=NODIR | GLOBSTAR | DOTGLOB | GLOBTILDE | BRACE | FOLLOW | IGNORECASE, ): file_path = Path(file).resolve() logger.debug(f"Configuration file found at {file_path}") yield file_path, file_path.read_text(encoding="utf-8")
[docs] def parse_conf(self, conf_text: str) -> dict[str, Any] | None: """Try to parse the provided content with each format in the order provided by the user. A successful parsing in any format is supposed to return a ``dict``. Any other result, including any raised exception, is considered a failure and the next format is tried. """ logger = logging.getLogger("click_extra") user_conf = None for conf_format in self.formats: logger.debug(f"Parse configuration as {conf_format.name}...") try: if conf_format == Formats.TOML: user_conf = tomllib.loads(conf_text) elif conf_format == Formats.YAML: user_conf = yaml.full_load(conf_text) elif conf_format == Formats.JSON: user_conf = json.loads(conf_text) elif conf_format == Formats.INI: user_conf = self.load_ini_config(conf_text) elif conf_format == Formats.XML: user_conf = xmltodict.parse(conf_text) except Exception as ex: logger.debug(ex) continue if isinstance(user_conf, dict): return user_conf else: logger.debug(f"{conf_format.name} parsing failed.") return None
[docs] def read_and_parse_conf( self, pattern: str, ) -> tuple[Path | URL, dict[str, Any]] | tuple[None, None]: """Search for a configuration file matching the provided pattern. Returns the location and parsed content of the first valid configuration file that is not blank, or `(None, None)` if no file was found. """ for conf_path, conf_text in self.search_and_read_conf(pattern): user_conf = self.parse_conf(conf_text) if user_conf is not None: return conf_path, user_conf return None, None
[docs] def load_ini_config(self, content: str) -> dict[str, Any]: """Utility method to parse INI configuration file. Internal convention is to use a dot (``.``, as set by ``self.SEP``) in section IDs as a separator between levels. This is a workaround the limitation of ``INI`` format which doesn't allow for sub-sections. Returns a ready-to-use data structure. """ ini_config = ConfigParser(interpolation=ExtendedInterpolation()) ini_config.read_string(content) conf: dict[str, Any] = {} for section_id in ini_config.sections(): # Extract all options of the section. sub_conf = {} for option_id in ini_config.options(section_id): target_type = self.get_tree_value( self.params_types, section_id, option_id, ) value: Any if target_type in (None, str): value = ini_config.get(section_id, option_id) elif target_type is int: value = ini_config.getint(section_id, option_id) elif target_type is float: value = ini_config.getfloat(section_id, option_id) elif target_type is bool: value = ini_config.getboolean(section_id, option_id) # Types not natively supported by INI format are loaded as # JSON-serialized strings. elif target_type in (list, tuple, set, frozenset, dict): value = json.loads(ini_config.get(section_id, option_id)) else: msg = ( f"Conversion of {target_type} type for " f"[{section_id}]:{option_id} INI config option." ) raise ValueError(msg) sub_conf[option_id] = value # Place collected options at the right level of the dict tree. merge(conf, self.init_tree_dict(*section_id.split(self.SEP), leaf=sub_conf)) return conf
[docs] def merge_default_map(self, ctx: Context, user_conf: dict) -> None: """Save the user configuration into the context's ``default_map``. Merge the user configuration into the pre-computed template structure, which will filter out all unrecognized options not supported by the command. Then cleans up blank values and update the context's ``default_map``. """ filtered_conf = _recursive_update(self.params_template, user_conf, self.strict) # Clean-up the conf by removing all blank values left-over by the template # structure. clean_conf = _remove_blanks(filtered_conf, remove_str=False) # Update the default_map. if ctx.default_map is None: ctx.default_map = {} ctx.default_map.update(clean_conf.get(ctx.find_root().command.name, {}))
[docs] def load_conf(self, ctx: Context, param: Parameter, path_pattern: str) -> None: """Fetch parameters values from configuration file and sets them as defaults. User configuration is merged to the `context's default_map <https://click.palletsprojects.com/en/stable/commands/#overriding-defaults>`_, `like Click does <https://click.palletsprojects.com/en/stable/commands/#context-defaults>`_. By relying on Click's default_map, we make sure that precedence is respected. And direct CLI parameters, environment variables or interactive prompts takes precedence over any values from the config file. """ logger = logging.getLogger("click_extra") explicit_conf = ctx.get_parameter_source("config") in ( ParameterSource.COMMANDLINE, ParameterSource.ENVIRONMENT, ParameterSource.PROMPT, ) message = f"Load configuration matching {path_pattern}" # Force printing of configuration location if the user explicitly set it. if explicit_conf: # We have can't simply use logger.info() here as the defaults have not been # loaded yet and the logger is stuck to its default WARNING level. echo(message, err=True) else: logger.debug(message) # Read configuration file. conf_path, user_conf = self.read_and_parse_conf(path_pattern) ctx.meta["click_extra.conf_source"] = conf_path ctx.meta["click_extra.conf_full"] = user_conf # Exit the CLI if no user-provided config file was found. if user_conf is None: message = "No configuration file found." if explicit_conf: logger.critical(message) ctx.exit(2) else: logger.debug(message) else: logger.debug(f"Parsed user configuration: {user_conf}") logger.debug(f"Initial defaults: {ctx.default_map}") self.merge_default_map(ctx, user_conf) logger.debug(f"New defaults: {ctx.default_map}")