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Diffstat (limited to 'Lib/packaging/metadata.py')
| -rw-r--r-- | Lib/packaging/metadata.py | 552 |
1 files changed, 552 insertions, 0 deletions
diff --git a/Lib/packaging/metadata.py b/Lib/packaging/metadata.py new file mode 100644 index 0000000..596eec7 --- /dev/null +++ b/Lib/packaging/metadata.py @@ -0,0 +1,552 @@ +"""Implementation of the Metadata for Python packages PEPs. + +Supports all metadata formats (1.0, 1.1, 1.2). +""" + +import re +import logging + +from io import StringIO +from email import message_from_file +from packaging import logger +from packaging.markers import interpret +from packaging.version import (is_valid_predicate, is_valid_version, + is_valid_versions) +from packaging.errors import (MetadataMissingError, + MetadataConflictError, + MetadataUnrecognizedVersionError) + +try: + # docutils is installed + from docutils.utils import Reporter + from docutils.parsers.rst import Parser + from docutils import frontend + from docutils import nodes + + class SilentReporter(Reporter): + + def __init__(self, source, report_level, halt_level, stream=None, + debug=0, encoding='ascii', error_handler='replace'): + self.messages = [] + Reporter.__init__(self, source, report_level, halt_level, stream, + debug, encoding, error_handler) + + def system_message(self, level, message, *children, **kwargs): + self.messages.append((level, message, children, kwargs)) + + _HAS_DOCUTILS = True +except ImportError: + # docutils is not installed + _HAS_DOCUTILS = False + +# public API of this module +__all__ = ['Metadata', 'PKG_INFO_ENCODING', 'PKG_INFO_PREFERRED_VERSION'] + +# Encoding used for the PKG-INFO files +PKG_INFO_ENCODING = 'utf-8' + +# preferred version. Hopefully will be changed +# to 1.2 once PEP 345 is supported everywhere +PKG_INFO_PREFERRED_VERSION = '1.0' + +_LINE_PREFIX = re.compile('\n \|') +_241_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform', + 'Summary', 'Description', + 'Keywords', 'Home-page', 'Author', 'Author-email', + 'License') + +_314_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform', + 'Supported-Platform', 'Summary', 'Description', + 'Keywords', 'Home-page', 'Author', 'Author-email', + 'License', 'Classifier', 'Download-URL', 'Obsoletes', + 'Provides', 'Requires') + +_314_MARKERS = ('Obsoletes', 'Provides', 'Requires') + +_345_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform', + 'Supported-Platform', 'Summary', 'Description', + 'Keywords', 'Home-page', 'Author', 'Author-email', + 'Maintainer', 'Maintainer-email', 'License', + 'Classifier', 'Download-URL', 'Obsoletes-Dist', + 'Project-URL', 'Provides-Dist', 'Requires-Dist', + 'Requires-Python', 'Requires-External') + +_345_MARKERS = ('Provides-Dist', 'Requires-Dist', 'Requires-Python', + 'Obsoletes-Dist', 'Requires-External', 'Maintainer', + 'Maintainer-email', 'Project-URL') + +_ALL_FIELDS = set() +_ALL_FIELDS.update(_241_FIELDS) +_ALL_FIELDS.update(_314_FIELDS) +_ALL_FIELDS.update(_345_FIELDS) + + +def _version2fieldlist(version): + if version == '1.0': + return _241_FIELDS + elif version == '1.1': + return _314_FIELDS + elif version == '1.2': + return _345_FIELDS + raise MetadataUnrecognizedVersionError(version) + + +def _best_version(fields): + """Detect the best version depending on the fields used.""" + def _has_marker(keys, markers): + for marker in markers: + if marker in keys: + return True + return False + + keys = list(fields) + possible_versions = ['1.0', '1.1', '1.2'] + + # first let's try to see if a field is not part of one of the version + for key in keys: + if key not in _241_FIELDS and '1.0' in possible_versions: + possible_versions.remove('1.0') + if key not in _314_FIELDS and '1.1' in possible_versions: + possible_versions.remove('1.1') + if key not in _345_FIELDS and '1.2' in possible_versions: + possible_versions.remove('1.2') + + # possible_version contains qualified versions + if len(possible_versions) == 1: + return possible_versions[0] # found ! + elif len(possible_versions) == 0: + raise MetadataConflictError('Unknown metadata set') + + # let's see if one unique marker is found + is_1_1 = '1.1' in possible_versions and _has_marker(keys, _314_MARKERS) + is_1_2 = '1.2' in possible_versions and _has_marker(keys, _345_MARKERS) + if is_1_1 and is_1_2: + raise MetadataConflictError('You used incompatible 1.1 and 1.2 fields') + + # we have the choice, either 1.0, or 1.2 + # - 1.0 has a broken Summary field but works with all tools + # - 1.1 is to avoid + # - 1.2 fixes Summary but is not widespread yet + if not is_1_1 and not is_1_2: + # we couldn't find any specific marker + if PKG_INFO_PREFERRED_VERSION in possible_versions: + return PKG_INFO_PREFERRED_VERSION + if is_1_1: + return '1.1' + + # default marker when 1.0 is disqualified + return '1.2' + + +_ATTR2FIELD = { + 'metadata_version': 'Metadata-Version', + 'name': 'Name', + 'version': 'Version', + 'platform': 'Platform', + 'supported_platform': 'Supported-Platform', + 'summary': 'Summary', + 'description': 'Description', + 'keywords': 'Keywords', + 'home_page': 'Home-page', + 'author': 'Author', + 'author_email': 'Author-email', + 'maintainer': 'Maintainer', + 'maintainer_email': 'Maintainer-email', + 'license': 'License', + 'classifier': 'Classifier', + 'download_url': 'Download-URL', + 'obsoletes_dist': 'Obsoletes-Dist', + 'provides_dist': 'Provides-Dist', + 'requires_dist': 'Requires-Dist', + 'requires_python': 'Requires-Python', + 'requires_external': 'Requires-External', + 'requires': 'Requires', + 'provides': 'Provides', + 'obsoletes': 'Obsoletes', + 'project_url': 'Project-URL', +} + +_PREDICATE_FIELDS = ('Requires-Dist', 'Obsoletes-Dist', 'Provides-Dist') +_VERSIONS_FIELDS = ('Requires-Python',) +_VERSION_FIELDS = ('Version',) +_LISTFIELDS = ('Platform', 'Classifier', 'Obsoletes', + 'Requires', 'Provides', 'Obsoletes-Dist', + 'Provides-Dist', 'Requires-Dist', 'Requires-External', + 'Project-URL', 'Supported-Platform') +_LISTTUPLEFIELDS = ('Project-URL',) + +_ELEMENTSFIELD = ('Keywords',) + +_UNICODEFIELDS = ('Author', 'Maintainer', 'Summary', 'Description') + +_MISSING = object() + + +class NoDefault: + """Marker object used for clean representation""" + def __repr__(self): + return '<NoDefault>' + +_MISSING = NoDefault() + + +class Metadata: + """The metadata of a release. + + Supports versions 1.0, 1.1 and 1.2 (auto-detected). You can + instantiate the class with one of these arguments (or none): + - *path*, the path to a METADATA file + - *fileobj* give a file-like object with METADATA as content + - *mapping* is a dict-like object + """ + # TODO document that execution_context and platform_dependent are used + # to filter on query, not when setting a key + # also document the mapping API and UNKNOWN default key + + def __init__(self, path=None, platform_dependent=False, + execution_context=None, fileobj=None, mapping=None): + self._fields = {} + self.requires_files = [] + self.docutils_support = _HAS_DOCUTILS + self.platform_dependent = platform_dependent + self.execution_context = execution_context + if [path, fileobj, mapping].count(None) < 2: + raise TypeError('path, fileobj and mapping are exclusive') + if path is not None: + self.read(path) + elif fileobj is not None: + self.read_file(fileobj) + elif mapping is not None: + self.update(mapping) + + def _set_best_version(self): + self._fields['Metadata-Version'] = _best_version(self._fields) + + def _write_field(self, file, name, value): + file.write('%s: %s\n' % (name, value)) + + def __getitem__(self, name): + return self.get(name) + + def __setitem__(self, name, value): + return self.set(name, value) + + def __delitem__(self, name): + field_name = self._convert_name(name) + try: + del self._fields[field_name] + except KeyError: + raise KeyError(name) + self._set_best_version() + + def __contains__(self, name): + return (name in self._fields or + self._convert_name(name) in self._fields) + + def _convert_name(self, name): + if name in _ALL_FIELDS: + return name + name = name.replace('-', '_').lower() + return _ATTR2FIELD.get(name, name) + + def _default_value(self, name): + if name in _LISTFIELDS or name in _ELEMENTSFIELD: + return [] + return 'UNKNOWN' + + def _check_rst_data(self, data): + """Return warnings when the provided data has syntax errors.""" + source_path = StringIO() + parser = Parser() + settings = frontend.OptionParser().get_default_values() + settings.tab_width = 4 + settings.pep_references = None + settings.rfc_references = None + reporter = SilentReporter(source_path, + settings.report_level, + settings.halt_level, + stream=settings.warning_stream, + debug=settings.debug, + encoding=settings.error_encoding, + error_handler=settings.error_encoding_error_handler) + + document = nodes.document(settings, reporter, source=source_path) + document.note_source(source_path, -1) + try: + parser.parse(data, document) + except AttributeError: + reporter.messages.append((-1, 'Could not finish the parsing.', + '', {})) + + return reporter.messages + + def _platform(self, value): + if not self.platform_dependent or ';' not in value: + return True, value + value, marker = value.split(';') + return interpret(marker, self.execution_context), value + + def _remove_line_prefix(self, value): + return _LINE_PREFIX.sub('\n', value) + + # + # Public API + # + def get_fullname(self): + """Return the distribution name with version""" + return '%s-%s' % (self['Name'], self['Version']) + + def is_metadata_field(self, name): + """return True if name is a valid metadata key""" + name = self._convert_name(name) + return name in _ALL_FIELDS + + def is_multi_field(self, name): + name = self._convert_name(name) + return name in _LISTFIELDS + + def read(self, filepath): + """Read the metadata values from a file path.""" + with open(filepath, 'r', encoding='utf-8') as fp: + self.read_file(fp) + + def read_file(self, fileob): + """Read the metadata values from a file object.""" + msg = message_from_file(fileob) + self._fields['Metadata-Version'] = msg['metadata-version'] + + for field in _version2fieldlist(self['Metadata-Version']): + if field in _LISTFIELDS: + # we can have multiple lines + values = msg.get_all(field) + if field in _LISTTUPLEFIELDS and values is not None: + values = [tuple(value.split(',')) for value in values] + self.set(field, values) + else: + # single line + value = msg[field] + if value is not None and value != 'UNKNOWN': + self.set(field, value) + + def write(self, filepath): + """Write the metadata fields to filepath.""" + with open(filepath, 'w', encoding='utf-8') as fp: + self.write_file(fp) + + def write_file(self, fileobject): + """Write the PKG-INFO format data to a file object.""" + self._set_best_version() + for field in _version2fieldlist(self['Metadata-Version']): + values = self.get(field) + if field in _ELEMENTSFIELD: + self._write_field(fileobject, field, ','.join(values)) + continue + if field not in _LISTFIELDS: + if field == 'Description': + values = values.replace('\n', '\n |') + values = [values] + + if field in _LISTTUPLEFIELDS: + values = [','.join(value) for value in values] + + for value in values: + self._write_field(fileobject, field, value) + + def update(self, other=None, **kwargs): + """Set metadata values from the given iterable `other` and kwargs. + + Behavior is like `dict.update`: If `other` has a ``keys`` method, + they are looped over and ``self[key]`` is assigned ``other[key]``. + Else, ``other`` is an iterable of ``(key, value)`` iterables. + + Keys that don't match a metadata field or that have an empty value are + dropped. + """ + def _set(key, value): + if key in _ATTR2FIELD and value: + self.set(self._convert_name(key), value) + + if other is None: + pass + elif hasattr(other, 'keys'): + for k in other.keys(): + _set(k, other[k]) + else: + for k, v in other: + _set(k, v) + + if kwargs: + self.update(kwargs) + + def set(self, name, value): + """Control then set a metadata field.""" + name = self._convert_name(name) + + if ((name in _ELEMENTSFIELD or name == 'Platform') and + not isinstance(value, (list, tuple))): + if isinstance(value, str): + value = [v.strip() for v in value.split(',')] + else: + value = [] + elif (name in _LISTFIELDS and + not isinstance(value, (list, tuple))): + if isinstance(value, str): + value = [value] + else: + value = [] + + if logger.isEnabledFor(logging.WARNING): + if name in _PREDICATE_FIELDS and value is not None: + for v in value: + # check that the values are valid predicates + if not is_valid_predicate(v.split(';')[0]): + logger.warning( + '%r is not a valid predicate (field %r)', + v, name) + # FIXME this rejects UNKNOWN, is that right? + elif name in _VERSIONS_FIELDS and value is not None: + if not is_valid_versions(value): + logger.warning('%r is not a valid version (field %r)', + value, name) + elif name in _VERSION_FIELDS and value is not None: + if not is_valid_version(value): + logger.warning('%r is not a valid version (field %r)', + value, name) + + if name in _UNICODEFIELDS: + if name == 'Description': + value = self._remove_line_prefix(value) + + self._fields[name] = value + self._set_best_version() + + def get(self, name, default=_MISSING): + """Get a metadata field.""" + name = self._convert_name(name) + if name not in self._fields: + if default is _MISSING: + default = self._default_value(name) + return default + if name in _UNICODEFIELDS: + value = self._fields[name] + return value + elif name in _LISTFIELDS: + value = self._fields[name] + if value is None: + return [] + res = [] + for val in value: + valid, val = self._platform(val) + if not valid: + continue + if name not in _LISTTUPLEFIELDS: + res.append(val) + else: + # That's for Project-URL + res.append((val[0], val[1])) + return res + + elif name in _ELEMENTSFIELD: + valid, value = self._platform(self._fields[name]) + if not valid: + return [] + if isinstance(value, str): + return value.split(',') + valid, value = self._platform(self._fields[name]) + if not valid: + return None + return value + + def check(self, strict=False, restructuredtext=False): + """Check if the metadata is compliant. If strict is False then raise if + no Name or Version are provided""" + # XXX should check the versions (if the file was loaded) + missing, warnings = [], [] + + for attr in ('Name', 'Version'): # required by PEP 345 + if attr not in self: + missing.append(attr) + + if strict and missing != []: + msg = 'missing required metadata: %s' % ', '.join(missing) + raise MetadataMissingError(msg) + + for attr in ('Home-page', 'Author'): + if attr not in self: + missing.append(attr) + + if _HAS_DOCUTILS and restructuredtext: + warnings.extend(self._check_rst_data(self['Description'])) + + # checking metadata 1.2 (XXX needs to check 1.1, 1.0) + if self['Metadata-Version'] != '1.2': + return missing, warnings + + def is_valid_predicates(value): + for v in value: + if not is_valid_predicate(v.split(';')[0]): + return False + return True + + for fields, controller in ((_PREDICATE_FIELDS, is_valid_predicates), + (_VERSIONS_FIELDS, is_valid_versions), + (_VERSION_FIELDS, is_valid_version)): + for field in fields: + value = self.get(field, None) + if value is not None and not controller(value): + warnings.append('Wrong value for %r: %s' % (field, value)) + + return missing, warnings + + def todict(self): + """Return fields as a dict. + + Field names will be converted to use the underscore-lowercase style + instead of hyphen-mixed case (i.e. home_page instead of Home-page). + """ + data = { + 'metadata_version': self['Metadata-Version'], + 'name': self['Name'], + 'version': self['Version'], + 'summary': self['Summary'], + 'home_page': self['Home-page'], + 'author': self['Author'], + 'author_email': self['Author-email'], + 'license': self['License'], + 'description': self['Description'], + 'keywords': self['Keywords'], + 'platform': self['Platform'], + 'classifier': self['Classifier'], + 'download_url': self['Download-URL'], + } + + if self['Metadata-Version'] == '1.2': + data['requires_dist'] = self['Requires-Dist'] + data['requires_python'] = self['Requires-Python'] + data['requires_external'] = self['Requires-External'] + data['provides_dist'] = self['Provides-Dist'] + data['obsoletes_dist'] = self['Obsoletes-Dist'] + data['project_url'] = [','.join(url) for url in + self['Project-URL']] + + elif self['Metadata-Version'] == '1.1': + data['provides'] = self['Provides'] + data['requires'] = self['Requires'] + data['obsoletes'] = self['Obsoletes'] + + return data + + # Mapping API + + def keys(self): + return _version2fieldlist(self['Metadata-Version']) + + def __iter__(self): + for key in self.keys(): + yield key + + def values(self): + return [self[key] for key in list(self.keys())] + + def items(self): + return [(key, self[key]) for key in list(self.keys())] |