# vim: fileencoding=utf-8
#
# A python interface for various rfc822-like formatted files used by Debian
# (.changes, .dsc, Packages, Sources, etc)
#
# Copyright (C) 2005-2006 dann frazier <dannf@dannf.org>
# Copyright (C) 2006-2010 John Wright <john@johnwright.org>
# Copyright (C) 2006 Adeodato Simó <dato@net.com.org.es>
# Copyright (C) 2008 Stefano Zacchiroli <zack@upsilon.cc>
# Copyright (C) 2014 Google, Inc.
#
# 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
from __future__ import absolute_import, print_function
from debian.deprecation import function_deprecated_by
try:
import apt_pkg
# This module uses apt_pkg only for its TagFile interface.
apt_pkg.TagFile
_have_apt_pkg = True
except (ImportError, AttributeError):
_have_apt_pkg = False
import chardet
import collections
import datetime
import email.utils
import re
import subprocess
import sys
import warnings
from io import BytesIO, StringIO
import six
if sys.version >= '3':
import io
def _is_real_file(f):
if not isinstance(f, io.IOBase):
return False
try:
f.fileno()
return True
except (AttributeError, io.UnsupportedOperation):
return False
else:
def _is_real_file(f):
return isinstance(f, file) and hasattr(f, 'fileno')
GPGV_DEFAULT_KEYRINGS = frozenset(['/usr/share/keyrings/debian-keyring.gpg'])
GPGV_EXECUTABLE = '/usr/bin/gpgv'
class Error(Exception):
"""Base class for custom exceptions in this module."""
class RestrictedFieldError(Error):
"""Raised when modifying the raw value of a field is not allowed."""
class TagSectionWrapper(collections.Mapping):
"""Wrap a TagSection object, using its find_raw method to get field values
This allows us to pick which whitespace to strip off the beginning and end
of the data, so we don't lose leading newlines.
"""
def __init__(self, section):
self.__section = section
def __iter__(self):
for key in self.__section.keys():
if not key.startswith('#'):
yield key
def __len__(self):
return len([key for key in self.__section.keys()
if not key.startswith('#')])
def __getitem__(self, key):
s = self.__section.find_raw(key)
if s is None:
raise KeyError(key)
# Get just the stuff after the first ':'
# Could use s.partition if we only supported python >= 2.5
data = s[s.find(b':')+1:]
# Get rid of spaces and tabs after the ':', but not newlines, and strip
# off any newline at the end of the data.
return data.lstrip(b' \t').rstrip(b'\n')
class OrderedSet(object):
"""A set-like object that preserves order when iterating over it
We use this to keep track of keys in Deb822Dict, because it's much faster
to look up if a key is in a set than in a list.
"""
def __init__(self, iterable=[]):
self.__set = set()
self.__order = []
for item in iterable:
self.add(item)
def add(self, item):
if item not in self:
# set.add will raise TypeError if something's unhashable, so we
# don't have to handle that ourselves
self.__set.add(item)
self.__order.append(item)
def remove(self, item):
# set.remove will raise KeyError, so we don't need to handle that
# ourselves
self.__set.remove(item)
self.__order.remove(item)
def __iter__(self):
# Return an iterator of items in the order they were added
return iter(self.__order)
def __len__(self):
return len(self.__order)
def __contains__(self, item):
# This is what makes OrderedSet faster than using a list to keep track
# of keys. Lookup in a set is O(1) instead of O(n) for a list.
return item in self.__set
### list-like methods
append = add
def extend(self, iterable):
for item in iterable:
self.add(item)
###
class Deb822Dict(collections.MutableMapping):
"""A dictionary-like object suitable for storing RFC822-like data.
Deb822Dict behaves like a normal dict, except:
- key lookup is case-insensitive
- key order is preserved
- if initialized with a _parsed parameter, it will pull values from
that dictionary-like object as needed (rather than making a copy).
The _parsed dict is expected to be able to handle case-insensitive
keys.
If _parsed is not None, an optional _fields parameter specifies which keys
in the _parsed dictionary are exposed.
"""
# See the end of the file for the definition of _strI
def __init__(self, _dict=None, _parsed=None, _fields=None,
encoding="utf-8"):
self.__dict = {}
self.__keys = OrderedSet()
self.__parsed = None
self.encoding = encoding
if _dict is not None:
# _dict may be a dict or a list of two-sized tuples
if hasattr(_dict, 'items'):
items = _dict.items()
else:
items = list(_dict)
try:
for k, v in items:
self[k] = v
except ValueError:
this = len(self.__keys)
len_ = len(items[this])
raise ValueError('dictionary update sequence element #%d has '
'length %d; 2 is required' % (this, len_))
if _parsed is not None:
self.__parsed = _parsed
if _fields is None:
self.__keys.extend([ _strI(k) for k in self.__parsed ])
else:
self.__keys.extend([ _strI(f) for f in _fields if f in self.__parsed ])
def _detect_encoding(self, value):
"""If value is not already Unicode, decode it intelligently."""
if isinstance(value, bytes):
try:
return value.decode(self.encoding)
except UnicodeDecodeError as e:
# Evidently, the value wasn't encoded with the encoding the
# user specified. Try detecting it.
warnings.warn('decoding from %s failed; attempting to detect '
'the true encoding' % self.encoding,
UnicodeWarning)
result = chardet.detect(value)
try:
return value.decode(result['encoding'])
except UnicodeDecodeError:
raise e
else:
# Assume the rest of the paragraph is in this encoding as
# well (there's no sense in repeating this exercise for
# every field).
self.encoding = result['encoding']
else:
return value
### BEGIN collections.MutableMapping methods
def __iter__(self):
for key in self.__keys:
yield str(key)
def __len__(self):
return len(self.__keys)
def __setitem__(self, key, value):
key = _strI(key)
self.__keys.add(key)
self.__dict[key] = value
def __getitem__(self, key):
key = _strI(key)
try:
value = self.__dict[key]
except KeyError:
if self.__parsed is not None and key in self.__keys:
value = self.__parsed[key]
else:
raise
# TODO(jsw): Move the decoding logic into __setitem__ so that we decode
# it once instead of every time somebody asks for it. Even better if
# Deb822* classes dealt in pure unicode and didn't care about the
# encoding of the files they came from...but I don't know how to fix
# that without breaking a bunch of users.
return self._detect_encoding(value)
def __delitem__(self, key):
key = _strI(key)
self.__keys.remove(key)
try:
del self.__dict[key]
except KeyError:
# If we got this far, the key was in self.__keys, so it must have
# only been in the self.__parsed dict.
pass
def __contains__(self, key):
key = _strI(key)
return key in self.__keys
if sys.version < '3':
has_key = __contains__
### END collections.MutableMapping methods
def __repr__(self):
return '{%s}' % ', '.join(['%r: %r' % (k, v) for k, v in self.items()])
def __eq__(self, other):
mykeys = sorted(self)
otherkeys = sorted(other)
if not mykeys == otherkeys:
return False
for key in mykeys:
if self[key] != other[key]:
return False
# If we got here, everything matched
return True
# Overriding __eq__ blocks inheritance of __hash__ in Python 3, and
# instances of this class are not sensibly hashable anyway.
__hash__ = None
def copy(self):
# Use self.__class__ so this works as expected for subclasses
copy = self.__class__(self)
return copy
# TODO implement __str__() and make dump() use that?
class Deb822(Deb822Dict):
def __init__(self, sequence=None, fields=None, _parsed=None,
encoding="utf-8"):
"""Create a new Deb822 instance.
:param sequence: a string, or any any object that returns a line of
input each time, normally a file. Alternately, sequence can
be a dict that contains the initial key-value pairs. When
python-apt is present, sequence can also be a compressed object,
for example a file object associated to something.gz.
:param fields: if given, it is interpreted as a list of fields that
should be parsed (the rest will be discarded).
:param _parsed: internal parameter.
:param encoding: When parsing strings, interpret them in this encoding.
(All values are given back as unicode objects, so an encoding is
necessary in order to properly interpret the strings.)
"""
if hasattr(sequence, 'items'):
_dict = sequence
sequence = None
else:
_dict = None
Deb822Dict.__init__(self, _dict=_dict, _parsed=_parsed, _fields=fields,
encoding=encoding)
if sequence is not None:
try:
self._internal_parser(sequence, fields)
except EOFError:
pass
self.gpg_info = None
@classmethod
def iter_paragraphs(cls, sequence, fields=None, use_apt_pkg=False,
shared_storage=False, encoding="utf-8"):
"""Generator that yields a Deb822 object for each paragraph in sequence.
:param sequence: same as in __init__.
:param fields: likewise.
:param use_apt_pkg: if sequence is a file, apt_pkg can be used
if available to parse the file, since it's much much faster. Set
this parameter to True to enable use of apt_pkg. Note that the
TagFile parser from apt_pkg is a much stricter parser of the
Deb822 format, particularly with regards whitespace between
paragraphs and comments within paragraphs. If these features are
required (for example in debian/control files), ensure that this
parameter is set to False.
:param shared_storage: not used, here for historical reasons. Deb822
objects never use shared storage anymore.
:param encoding: Interpret the paragraphs in this encoding.
(All values are given back as unicode objects, so an encoding is
necessary in order to properly interpret the strings.)
"""
if _have_apt_pkg and use_apt_pkg and _is_real_file(sequence):
kwargs = {}
if sys.version >= '3':
# bytes=True is supported for both Python 2 and 3, but we
# only actually need it for Python 3, so this saves us from
# having to require a newer version of python-apt for Python
# 2 as well. This allows us to apply our own encoding
# handling, which is more tolerant of mixed-encoding files.
kwargs['bytes'] = True
parser = apt_pkg.TagFile(sequence, **kwargs)
for section in parser:
paragraph = cls(fields=fields,
_parsed=TagSectionWrapper(section),
encoding=encoding)
if paragraph:
yield paragraph
else:
if isinstance(sequence, six.string_types + (six.binary_type,)):
sequence = sequence.splitlines()
iterable = iter(sequence)
while True:
x = cls(iterable, fields, encoding=encoding)
if not x:
break
yield x
###
@staticmethod
def _skip_useless_lines(sequence):
"""Yields only lines that do not begin with '#'.
Also skips any blank lines at the beginning of the input.
"""
at_beginning = True
for line in sequence:
# The bytes/str polymorphism required here to support Python 3
# is unpleasant, but fortunately limited. We need this because
# at this point we might have been given either bytes or
# Unicode, and we haven't yet got to the point where we can try
# to decode a whole paragraph and detect its encoding.
if isinstance(line, bytes):
if line.startswith(b'#'):
continue
else:
if line.startswith('#'):
continue
if at_beginning:
if isinstance(line, bytes):
if not line.rstrip(b'\r\n'):
continue
else:
if not line.rstrip('\r\n'):
continue
at_beginning = False
yield line
def _internal_parser(self, sequence, fields=None):
# The key is non-whitespace, non-colon characters before any colon.
key_part = r"^(?P<key>[^: \t\n\r\f\v]+)\s*:\s*"
single = re.compile(key_part + r"(?P<data>\S.*?)\s*$")
multi = re.compile(key_part + r"$")
multidata = re.compile(r"^\s(?P<data>.+?)\s*$")
wanted_field = lambda f: fields is None or f in fields
if isinstance(sequence, (six.string_types, bytes)):
sequence = sequence.splitlines()
curkey = None
content = ""
for line in self.gpg_stripped_paragraph(
self._skip_useless_lines(sequence)):
line = self._detect_encoding(line)
m = single.match(line)
if m:
if curkey:
self[curkey] = content
if not wanted_field(m.group('key')):
curkey = None
continue
curkey = m.group('key')
content = m.group('data')
continue
m = multi.match(line)
if m:
if curkey:
self[curkey] = content
if not wanted_field(m.group('key')):
curkey = None
continue
curkey = m.group('key')
content = ""
continue
m = multidata.match(line)
if m:
content += '\n' + line # XXX not m.group('data')?
continue
if curkey:
self[curkey] = content
def __str__(self):
return self.dump()
def __unicode__(self):
return self.dump()
if sys.version >= '3':
def __bytes__(self):
return self.dump().encode(self.encoding)
# __repr__ is handled by Deb822Dict
def get_as_string(self, key):
"""Return the self[key] as a string (or unicode)
The default implementation just returns unicode(self[key]); however,
this can be overridden in subclasses (e.g. _multivalued) that can take
special values.
"""
return six.text_type(self[key])
def dump(self, fd=None, encoding=None, text_mode=False):
"""Dump the the contents in the original format
If fd is None, returns a unicode object. Otherwise, fd is assumed to
be a file-like object, and this method will write the data to it
instead of returning a unicode object.
If fd is not none and text_mode is False, the data will be encoded
to a byte string before writing to the file. The encoding used is
chosen via the encoding parameter; None means to use the encoding the
object was initialized with (utf-8 by default). This will raise
UnicodeEncodeError if the encoding can't support all the characters in
the Deb822Dict values.
"""
# Ideally this would never try to encode (that should be up to the
# caller when opening the file), but we may still have users who rely
# on the binary mode encoding. But...might it be better to break them
# than to introduce yet another parameter relating to encoding?
if fd is None:
fd = StringIO()
return_string = True
else:
return_string = False
if encoding is None:
# Use the encoding we've been using to decode strings with if none
# was explicitly specified
encoding = self.encoding
for key in self:
value = self.get_as_string(key)
if not value or value[0] == '\n':
# Avoid trailing whitespace after "Field:" if it's on its own
# line or the value is empty. We don't have to worry about the
# case where value == '\n', since we ensure that is not the
# case in __setitem__.
entry = '%s:%s\n' % (key, value)
else:
entry = '%s: %s\n' % (key, value)
if not return_string and not text_mode:
fd.write(entry.encode(encoding))
else:
fd.write(entry)
if return_string:
return fd.getvalue()
###
def is_single_line(self, s):
if s.count("\n"):
return False
else:
return True
isSingleLine = function_deprecated_by(is_single_line)
def is_multi_line(self, s):
return not self.is_single_line(s)
isMultiLine = function_deprecated_by(is_multi_line)
def _merge_fields(self, s1, s2):
if not s2:
return s1
if not s1:
return s2
if self.is_single_line(s1) and self.is_single_line(s2):
## some fields are delimited by a single space, others
## a comma followed by a space. this heuristic assumes
## that there are multiple items in one of the string fields
## so that we can pick up on the delimiter being used
delim = ' '
if (s1 + s2).count(', '):
delim = ', '
L = sorted((s1 + delim + s2).split(delim))
prev = merged = L[0]
for item in L[1:]:
## skip duplicate entries
if item == prev:
continue
merged = merged + delim + item
prev = item
return merged
if self.is_multi_line(s1) and self.is_multi_line(s2):
for item in s2.splitlines(True):
if item not in s1.splitlines(True):
s1 = s1 + "\n" + item
return s1
raise ValueError
_mergeFields = function_deprecated_by(_merge_fields)
def merge_fields(self, key, d1, d2=None):
## this method can work in two ways - abstract that away
if d2 == None:
x1 = self
x2 = d1
else:
x1 = d1
x2 = d2
## we only have to do work if both objects contain our key
## otherwise, we just take the one that does, or raise an
## exception if neither does
if key in x1 and key in x2:
merged = self._mergeFields(x1[key], x2[key])
elif key in x1:
merged = x1[key]
elif key in x2:
merged = x2[key]
else:
raise KeyError
## back to the two different ways - if this method was called
## upon an object, update that object in place.
## return nothing in this case, to make the author notice a
## problem if she assumes the object itself will not be modified
if d2 == None:
self[key] = merged
return None
return merged
mergeFields = function_deprecated_by(merge_fields)
def split_gpg_and_payload(sequence):
"""Return a (gpg_pre, payload, gpg_post) tuple
Each element of the returned tuple is a list of lines (with trailing
whitespace stripped).
"""
gpg_pre_lines = []
lines = []
gpg_post_lines = []
state = b'SAFE'
gpgre = re.compile(br'^-----(?P<action>BEGIN|END) PGP (?P<what>[^-]+)-----[\r\t ]*$')
# Include whitespace-only lines in blank lines to split paragraphs.
# (see #715558)
blank_line = re.compile(br'^\s*$')
first_line = True
for line in sequence:
# Some consumers of this method require bytes (encoding
# detection and signature checking). However, we might have
# been given a file opened in text mode, in which case it's
# simplest to encode to bytes.
if sys.version >= '3' and isinstance(line, str):
line = line.encode()
line = line.strip(b'\r\n')
# skip initial blank lines, if any
if first_line:
if blank_line.match(line):
continue
else:
first_line = False
m = gpgre.match(line)
if not m:
if state == b'SAFE':
if not blank_line.match(line):
lines.append(line)
else:
if not gpg_pre_lines:
# There's no gpg signature, so we should stop at
# this blank line
break
elif state == b'SIGNED MESSAGE':
if blank_line.match(line):
state = b'SAFE'
else:
gpg_pre_lines.append(line)
elif state == b'SIGNATURE':
gpg_post_lines.append(line)
else:
if m.group('action') == b'BEGIN':
state = m.group('what')
elif m.group('action') == b'END':
gpg_post_lines.append(line)
break
if not blank_line.match(line):
if not lines:
gpg_pre_lines.append(line)
else:
gpg_post_lines.append(line)
if len(lines):
return (gpg_pre_lines, lines, gpg_post_lines)
else:
raise EOFError('only blank lines found in input')
split_gpg_and_payload = staticmethod(split_gpg_and_payload)
def gpg_stripped_paragraph(cls, sequence):
return cls.split_gpg_and_payload(sequence)[1]
gpg_stripped_paragraph = classmethod(gpg_stripped_paragraph)
def get_gpg_info(self, keyrings=None):
"""Return a GpgInfo object with GPG signature information
This method will raise ValueError if the signature is not available
(e.g. the original text cannot be found).
:param keyrings: list of keyrings to use (see GpgInfo.from_sequence)
"""
# raw_text is saved (as a string) only for Changes and Dsc (see
# _gpg_multivalued.__init__) which is small compared to Packages or
# Sources which contain no signature
if not hasattr(self, 'raw_text'):
raise ValueError("original text cannot be found")
if self.gpg_info is None:
self.gpg_info = GpgInfo.from_sequence(self.raw_text,
keyrings=keyrings)
return self.gpg_info
def validate_input(self, key, value):
"""Raise ValueError if value is not a valid value for key
Subclasses that do interesting things for different keys may wish to
override this method.
"""
# The value cannot end in a newline (if it did, dumping the object
# would result in multiple stanzas)
if value.endswith('\n'):
raise ValueError("value must not end in '\\n'")
# Make sure there are no blank lines (actually, the first one is
# allowed to be blank, but no others), and each subsequent line starts
# with whitespace
for line in value.splitlines()[1:]:
if not line:
raise ValueError("value must not have blank lines")
if not line[0].isspace():
raise ValueError("each line must start with whitespace")
def __setitem__(self, key, value):
self.validate_input(key, value)
Deb822Dict.__setitem__(self, key, value)
# XXX check what happens if input contains more that one signature
class GpgInfo(dict):
"""A wrapper around gnupg parsable output obtained via --status-fd
This class is really a dictionary containing parsed output from gnupg plus
some methods to make sense of the data.
Keys are keywords and values are arguments suitably splitted.
See /usr/share/doc/gnupg/DETAILS.gz"""
# keys with format "key keyid uid"
uidkeys = ('GOODSIG', 'EXPSIG', 'EXPKEYSIG', 'REVKEYSIG', 'BADSIG')
def valid(self):
"""Is the signature valid?"""
return 'GOODSIG' in self or 'VALIDSIG' in self
# XXX implement as a property?
# XXX handle utf-8 %-encoding
def uid(self):
"""Return the primary ID of the signee key, None is not available"""
pass
@classmethod
def from_output(cls, out, err=None):
"""Create a new GpgInfo object from gpg(v) --status-fd output (out) and
optionally collect stderr as well (err).
Both out and err can be lines in newline-terminated sequence or regular strings."""
n = cls()
if isinstance(out, six.string_types):
out = out.split('\n')
if isinstance(err, six.string_types):
err = err.split('\n')
n.out = out
n.err = err
header = '[GNUPG:] '
for l in out:
if not l.startswith(header):
continue
l = l[len(header):]
l = l.strip('\n')
# str.partition() would be better, 2.5 only though
s = l.find(' ')
key = l[:s]
if key in cls.uidkeys:
# value is "keyid UID", don't split UID
value = l[s+1:].split(' ', 1)
else:
value = l[s+1:].split(' ')
# Skip headers in the gpgv output that are not interesting
# note NEWSI is actually NEWSIG but the above parsing loses the 'G'
# if no keyid is included in the message. See
# /usr/share/doc/gnupg/DETAILS.gz
if key in ('NEWSI', 'NEWSIG', 'KEY_CONSIDERED', 'PROGRESS'):
continue
n[key] = value
return n
@classmethod
def from_sequence(cls, sequence, keyrings=None, executable=None):
"""Create a new GpgInfo object from the given sequence.
:param sequence: sequence of lines of bytes or a single byte string
:param keyrings: list of keyrings to use (default:
['/usr/share/keyrings/debian-keyring.gpg'])
:param executable: list of args for subprocess.Popen, the first element
being the gpgv executable (default: ['/usr/bin/gpgv'])
"""
keyrings = keyrings or GPGV_DEFAULT_KEYRINGS
executable = executable or [GPGV_EXECUTABLE]
# XXX check for gpg as well and use --verify accordingly?
args = list(executable)
#args.extend(["--status-fd", "1", "--no-default-keyring"])
args.extend(["--status-fd", "1"])
for k in keyrings:
args.extend(["--keyring", k])
if "--keyring" not in args:
raise IOError("cannot access any of the given keyrings")
p = subprocess.Popen(args, stdin=subprocess.PIPE,
stdout=subprocess.PIPE, stderr=subprocess.PIPE,
universal_newlines=False)
# XXX what to do with exit code?
if isinstance(sequence, bytes):
inp = sequence
else:
inp = cls._get_full_bytes(sequence)
out, err = p.communicate(inp)
return cls.from_output(out.decode('utf-8'),
err.decode('utf-8'))
@staticmethod
def _get_full_bytes(sequence):
"""Return a byte string from a sequence of lines of bytes.
This method detects if the sequence's lines are newline-terminated, and
constructs the byte string appropriately.
"""
# Peek at the first line to see if it's newline-terminated.
sequence_iter = iter(sequence)
try:
first_line = next(sequence_iter)
except StopIteration:
return b""
join_str = b'\n'
if first_line.endswith(b'\n'):
join_str = b''
return first_line + join_str + join_str.join(sequence_iter)
@classmethod
def from_file(cls, target, *args, **kwargs):
"""Create a new GpgInfo object from the given file.
See GpgInfo.from_sequence.
"""
with open(target, 'rb') as target_file:
return cls.from_sequence(target_file, *args, **kwargs)
class PkgRelation(object):
"""Inter-package relationships
Structured representation of the relationships of a package to another,
i.e. of what can appear in a Deb882 field like Depends, Recommends,
Suggests, ... (see Debian Policy 7.1).
"""
# XXX *NOT* a real dependency parser, and that is not even a goal here, we
# just parse as much as we need to split the various parts composing a
# dependency, checking their correctness wrt policy is out of scope
__dep_RE = re.compile(
r'^\s*(?P<name>[a-zA-Z0-9.+\-]{2,})'
r'(:(?P<archqual>([a-zA-Z0-9][a-zA-Z0-9-]*)))?'
r'(\s*\(\s*(?P<relop>[>=<]+)\s*'
r'(?P<version>[0-9a-zA-Z:\-+~.]+)\s*\))?'
r'(\s*\[(?P<archs>[\s!\w\-]+)\])?\s*'
r'((?P<restrictions><.+>))?\s*'
r'$')
__comma_sep_RE = re.compile(r'\s*,\s*')
__pipe_sep_RE = re.compile(r'\s*\|\s*')
__blank_sep_RE = re.compile(r'\s+')
__restriction_sep_RE = re.compile(r'>\s*<')
__restriction_RE = re.compile(
r'(?P<enabled>\!)?'
r'(?P<profile>[^\s]+)')
ArchRestriction = collections.namedtuple('ArchRestriction',
['enabled', 'arch'])
BuildRestriction = collections.namedtuple('BuildRestriction',
['enabled', 'profile'])
@classmethod
def parse_relations(cls, raw):
"""Parse a package relationship string (i.e. the value of a field like
Depends, Recommends, Build-Depends ...)
"""
def parse_archs(raw):
# assumption: no space between '!' and architecture name
archs = []
for arch in cls.__blank_sep_RE.split(raw.strip()):
disabled = arch[0] == '!'
if disabled:
arch = arch[1:]
archs.append(cls.ArchRestriction(not disabled, arch))
return archs
def parse_restrictions(raw):
""" split a restriction formula into a list of restriction lists
Each term in the restriction list is a namedtuple of form:
(enabled, label)
where
enabled: boolean: whether the restriction is positive or negative
profile: the profile name of the term e.g. 'stage1'
"""
restrictions = []
for rgrp in cls.__restriction_sep_RE.split(raw.lower().strip('<> ')):
group = []
for restriction in cls.__blank_sep_RE.split(rgrp):
match = cls.__restriction_RE.match(restriction)
if match:
parts = match.groupdict()
group.append(cls.BuildRestriction(
parts['enabled'] != '!',
parts['profile'],
))
restrictions.append(group)
return restrictions
def parse_rel(raw):
match = cls.__dep_RE.match(raw)
if match:
parts = match.groupdict()
d = {
'name': parts['name'],
'archqual': parts['archqual'],
'version': None,
'arch': None,
'restrictions': None,
}
if parts['relop'] or parts['version']:
d['version'] = (parts['relop'], parts['version'])
if parts['archs']:
d['arch'] = parse_archs(parts['archs'])
if parts['restrictions']:
d['restrictions'] = parse_restrictions(parts['restrictions'])
return d
else:
warnings.warn('cannot parse package' \
' relationship "%s", returning it raw' % raw)
return { 'name': raw, 'version': None, 'arch': None }
tl_deps = cls.__comma_sep_RE.split(raw.strip()) # top-level deps
cnf = map(cls.__pipe_sep_RE.split, tl_deps)
return [[parse_rel(or_dep) for or_dep in or_deps] for or_deps in cnf]
@staticmethod
def str(rels):
"""Format to string structured inter-package relationships
Perform the inverse operation of parse_relations, returning a string
suitable to be written in a package stanza.
"""
def pp_arch(arch_spec):
return '%s%s' % (
'' if arch_spec.enabled else '!',
arch_spec.arch,
)
def pp_restrictions(restrictions):
s = []
for term in restrictions:
s.append('%s%s' % (
'' if term.enabled else '!',
term.profile
)
)
return '<%s>' % ' '.join(s)
def pp_atomic_dep(dep):
s = dep['name']
if dep.get('archqual') is not None:
s += ':%s' % dep['archqual']
if dep.get('version') is not None:
s += ' (%s %s)' % dep['version']
if dep.get('arch') is not None:
s += ' [%s]' % ' '.join(map(pp_arch, dep['arch']))
if dep.get('restrictions') is not None:
s += ' %s' % ' '.join(map(pp_restrictions, dep['restrictions']))
return s
pp_or_dep = lambda deps: ' | '.join(map(pp_atomic_dep, deps))
return ', '.join(map(pp_or_dep, rels))
class _lowercase_dict(dict):
"""Dictionary wrapper which lowercase keys upon lookup."""
def __getitem__(self, key):
return dict.__getitem__(self, key.lower())
class _PkgRelationMixin(object):
"""Package relationship mixin
Inheriting from this mixin you can extend a Deb882 object with attributes
letting you access inter-package relationship in a structured way, rather
than as strings. For example, while you can usually use pkg['depends'] to
obtain the Depends string of package pkg, mixing in with this class you
gain pkg.depends to access Depends as a Pkgrel instance
To use, subclass _PkgRelationMixin from a class with a _relationship_fields
attribute. It should be a list of field names for which structured access
is desired; for each of them a method wild be added to the inherited class.
The method name will be the lowercase version of field name; '-' will be
mangled as '_'. The method would return relationships in the same format of
the PkgRelation' relations property.
See Packages and Sources as examples.
"""
def __init__(self, *args, **kwargs):
self.__relations = _lowercase_dict({})
self.__parsed_relations = False
for name in self._relationship_fields:
# To avoid reimplementing Deb822 key lookup logic we use a really
# simple dict subclass which just lowercase keys upon lookup. Since
# dictionary building happens only here, we ensure that all keys
# are in fact lowercase.
# With this trick we enable users to use the same key (i.e. field
# name) of Deb822 objects on the dictionary returned by the
# relations property.
keyname = name.lower()
if name in self:
self.__relations[keyname] = None # lazy value
# all lazy values will be expanded before setting
# __parsed_relations to True
else:
self.__relations[keyname] = []
@property
def relations(self):
"""Return a dictionary of inter-package relationships among the current
and other packages.
Dictionary keys depend on the package kind. Binary packages have keys
like 'depends', 'recommends', ... while source packages have keys like
'build-depends', 'build-depends-indep' and so on. See the Debian policy
for the comprehensive field list.
Dictionary values are package relationships returned as lists of lists
of dictionaries (see below for some examples).
The encoding of package relationships is as follows:
- the top-level lists corresponds to the comma-separated list of
Deb822, their components form a conjunction, i.e. they have to be
AND-ed together
- the inner lists corresponds to the pipe-separated list of Deb822,
their components form a disjunction, i.e. they have to be OR-ed
together
- member of the inner lists are dictionaries with the following keys:
- name: package (or virtual package) name
- version: A pair <operator, version> if the relationship is
versioned, None otherwise. operator is one of "<<",
"<=", "=", ">=", ">>"; version is the given version as
a string.
- arch: A list of pairs <enabled, arch> if the
relationship is architecture specific, None otherwise.
Enabled is a boolean (false if the architecture is
negated with "!", true otherwise), arch the
Debian architecture name as a string.
- restrictions: A list of lists of tuples <enabled, profile>
if there is a restriction formula defined, None
otherwise. Each list of tuples represents a restriction
list while each tuple represents an individual term
within the restriction list. Enabled is a boolean
(false if the restriction is negated with "!", true
otherwise). The profile is the name of the build
restriction.
https://wiki.debian.org/BuildProfileSpec
The arch and restrictions tuples are available as named tuples so
elements are available as term[0] or alternatively as
term.enabled (and so forth).
Examples:
"emacs | emacsen, make, debianutils (>= 1.7)" becomes
[ [ {'name': 'emacs'}, {'name': 'emacsen'} ],
[ {'name': 'make'} ],
[ {'name': 'debianutils', 'version': ('>=', '1.7')} ] ]
"tcl8.4-dev, procps [!hurd-i386]" becomes
[ [ {'name': 'tcl8.4-dev'} ],
[ {'name': 'procps', 'arch': (false, 'hurd-i386')} ] ]
"texlive <!cross>" becomes
[ [ {'name': 'texlive',
'restriction': [[(false, 'cross')]]} ] ]
"""
if not self.__parsed_relations:
lazy_rels = filter(lambda n: self.__relations[n] is None,
self.__relations.keys())
for n in lazy_rels:
self.__relations[n] = PkgRelation.parse_relations(self[n])
self.__parsed_relations = True
return self.__relations
class _multivalued(Deb822):
"""A class with (R/W) support for multivalued fields.
To use, create a subclass with a _multivalued_fields attribute. It should
be a dictionary with *lower-case* keys, with lists of human-readable
identifiers of the fields as the values. Please see Dsc, Changes, and
PdiffIndex as examples.
"""
def __init__(self, *args, **kwargs):
Deb822.__init__(self, *args, **kwargs)
for field, fields in self._multivalued_fields.items():
try:
contents = self[field]
except KeyError:
continue
if self.is_multi_line(contents):
self[field] = []
updater_method = self[field].append
else:
self[field] = Deb822Dict()
updater_method = self[field].update
for line in filter(None, contents.splitlines()):
updater_method(Deb822Dict(zip(fields, line.split())))
def validate_input(self, key, value):
if key.lower() in self._multivalued_fields:
# It's difficult to write a validator for multivalued fields, and
# basically futile, since we allow mutable lists. In any case,
# with sanity checking in get_as_string, we shouldn't ever output
# unparseable data.
pass
else:
Deb822.validate_input(self, key, value)
def get_as_string(self, key):
keyl = key.lower()
if keyl in self._multivalued_fields:
fd = StringIO()
if hasattr(self[key], 'keys'): # single-line
array = [ self[key] ]
else: # multi-line
fd.write(six.u("\n"))
array = self[key]
order = self._multivalued_fields[keyl]
try:
field_lengths = self._fixed_field_lengths
except AttributeError:
field_lengths = {}
for item in array:
for x in order:
raw_value = six.text_type(item[x])
try:
length = field_lengths[keyl][x]
except KeyError:
value = raw_value
else:
value = (length - len(raw_value)) * " " + raw_value
if "\n" in value:
raise ValueError("'\\n' not allowed in component of "
"multivalued field %s" % key)
fd.write(six.u(" %s") % value)
fd.write(six.u("\n"))
return fd.getvalue().rstrip("\n")
else:
return Deb822.get_as_string(self, key)
class _gpg_multivalued(_multivalued):
"""A _multivalued class that can support gpg signed objects
This class's feature is that it stores the raw text before parsing so that
gpg can verify the signature. Use it just like you would use the
_multivalued class.
This class only stores raw text if it is given a raw string, or if it
detects a gpg signature when given a file or sequence of lines (see
Deb822.split_gpg_and_payload for details).
"""
def __init__(self, *args, **kwargs):
try:
sequence = args[0]
except IndexError:
sequence = kwargs.get("sequence", None)
if sequence is not None:
# If the input is a unicode object or a file opened in text mode,
# we'll need to encode it back to bytes for gpg. If it's not
# actually in the encoding that we guess, then this probably won't
# verify correctly, but this is the best we can reasonably manage.
# For accurate verification, the file should be opened in binary
# mode.
encoding = (getattr(sequence, 'encoding', None)
or kwargs.get('encoding', 'utf-8') or 'utf-8')
if isinstance(sequence, bytes):
self.raw_text = sequence
elif isinstance(sequence, six.string_types):
self.raw_text = sequence.encode(encoding)
elif hasattr(sequence, "items"):
# sequence is actually a dict(-like) object, so we don't have
# the raw text.
pass
else:
try:
gpg_pre_lines, lines, gpg_post_lines = \
self.split_gpg_and_payload(
self._bytes(s, encoding) for s in sequence)
except EOFError:
# Empty input
gpg_pre_lines = lines = gpg_post_lines = []
if gpg_pre_lines and gpg_post_lines:
raw_text = BytesIO()
raw_text.write(b"\n".join(gpg_pre_lines))
raw_text.write(b"\n\n")
raw_text.write(b"\n".join(lines))
raw_text.write(b"\n\n")
raw_text.write(b"\n".join(gpg_post_lines))
self.raw_text = raw_text.getvalue()
try:
args = list(args)
args[0] = lines
except IndexError:
kwargs["sequence"] = lines
_multivalued.__init__(self, *args, **kwargs)
@staticmethod
def _bytes(s, encoding):
"""Converts s to bytes if necessary, using encoding.
If s is already bytes type, returns it directly.
"""
if isinstance(s, bytes):
return s
if isinstance(s, six.string_types):
return s.encode(encoding)
raise TypeError('bytes or unicode/string required, not %s' % type(s))
class Dsc(_gpg_multivalued):
_multivalued_fields = {
"files": [ "md5sum", "size", "name" ],
"checksums-sha1": ["sha1", "size", "name"],
"checksums-sha256": ["sha256", "size", "name"],
"checksums-sha512": ["sha512", "size", "name"],
}
class Changes(_gpg_multivalued):
_multivalued_fields = {
"files": [ "md5sum", "size", "section", "priority", "name" ],
"checksums-sha1": ["sha1", "size", "name"],
"checksums-sha256": ["sha256", "size", "name"],
"checksums-sha512": ["sha512", "size", "name"],
}
def get_pool_path(self):
"""Return the path in the pool where the files would be installed"""
# This is based on the section listed for the first file. While
# it is possible, I think, for a package to provide files in multiple
# sections, I haven't seen it in practice. In any case, this should
# probably detect such a situation and complain, or return a list...
s = self['files'][0]['section']
try:
section, subsection = s.split('/')
except ValueError:
# main is implicit
section = 'main'
if self['source'].startswith('lib'):
subdir = self['source'][:4]
else:
subdir = self['source'][0]
return 'pool/%s/%s/%s' % (section, subdir, self['source'])
class PdiffIndex(_multivalued):
_multivalued_fields = {
"sha1-current": [ "SHA1", "size" ],
"sha1-history": [ "SHA1", "size", "date" ],
"sha1-patches": [ "SHA1", "size", "date" ],
}
@property
def _fixed_field_lengths(self):
fixed_field_lengths = {}
for key in self._multivalued_fields:
if hasattr(self[key], 'keys'):
# Not multi-line -- don't need to compute the field length for
# this one
continue
length = self._get_size_field_length(key)
fixed_field_lengths[key] = {"size": length}
return fixed_field_lengths
def _get_size_field_length(self, key):
lengths = [len(str(item['size'])) for item in self[key]]
return max(lengths)
class Release(_multivalued):
"""Represents a Release file
Set the size_field_behavior attribute to "dak" to make the size field
length only as long as the longest actual value. The default,
"apt-ftparchive" makes the field 16 characters long regardless.
"""
# FIXME: Add support for detecting the behavior of the input, if
# constructed from actual 822 text.
_multivalued_fields = {
"md5sum": [ "md5sum", "size", "name" ],
"sha1": [ "sha1", "size", "name" ],
"sha256": [ "sha256", "size", "name" ],
"sha512": [ "sha512", "size", "name" ],
}
__size_field_behavior = "apt-ftparchive"
def set_size_field_behavior(self, value):
if value not in ["apt-ftparchive", "dak"]:
raise ValueError("size_field_behavior must be either "
"'apt-ftparchive' or 'dak'")
else:
self.__size_field_behavior = value
size_field_behavior = property(lambda self: self.__size_field_behavior,
set_size_field_behavior)
@property
def _fixed_field_lengths(self):
fixed_field_lengths = {}
for key in self._multivalued_fields:
length = self._get_size_field_length(key)
fixed_field_lengths[key] = {"size": length}
return fixed_field_lengths
def _get_size_field_length(self, key):
if self.size_field_behavior == "apt-ftparchive":
return 16
elif self.size_field_behavior == "dak":
lengths = [len(str(item['size'])) for item in self[key]]
return max(lengths)
class Sources(Dsc, _PkgRelationMixin):
"""Represent an APT source package list"""
_relationship_fields = [ 'build-depends', 'build-depends-indep',
'build-conflicts', 'build-conflicts-indep', 'binary' ]
def __init__(self, *args, **kwargs):
Dsc.__init__(self, *args, **kwargs)
_PkgRelationMixin.__init__(self, *args, **kwargs)
@classmethod
def iter_paragraphs(cls, sequence, fields=None, use_apt_pkg=True,
shared_storage=False, encoding="utf-8"):
"""Generator that yields a Deb822 object for each paragraph in Sources.
Note that this overloaded form of the generator uses apt_pkg (a strict
but fast parser) by default.
See the Deb822.iter_paragraphs function for details.
"""
return super(Sources, cls).iter_paragraphs(sequence, fields,
use_apt_pkg, shared_storage, encoding)
class Packages(Deb822, _PkgRelationMixin):
"""Represent an APT binary package list"""
_relationship_fields = [ 'depends', 'pre-depends', 'recommends',
'suggests', 'breaks', 'conflicts', 'provides', 'replaces',
'enhances' ]
def __init__(self, *args, **kwargs):
Deb822.__init__(self, *args, **kwargs)
_PkgRelationMixin.__init__(self, *args, **kwargs)
@classmethod
def iter_paragraphs(cls, sequence, fields=None, use_apt_pkg=True,
shared_storage=False, encoding="utf-8"):
"""Generator that yields a Deb822 object for each paragraph in Packages.
Note that this overloaded form of the generator uses apt_pkg (a strict
but fast parser) by default.
See the Deb822.iter_paragraphs function for details.
"""
return super(Packages, cls).iter_paragraphs(sequence, fields,
use_apt_pkg, shared_storage, encoding)
class _ClassInitMeta(type):
"""Metaclass for classes that can be initialized at creation time.
Implement the method
@classmethod
def _class_init(cls, new_attrs):
pass
on a class, and apply this metaclass to it. The _class_init method will be
called right after the class is created. The 'new_attrs' param is a dict
containing the attributes added in the definition of the class.
"""
def __init__(cls, name, bases, attrs):
super(_ClassInitMeta, cls).__init__(name, bases, attrs)
cls._class_init(attrs)
class RestrictedField(collections.namedtuple(
'RestrictedField', 'name from_str to_str allow_none')):
"""Placeholder for a property providing access to a restricted field.
Use this as an attribute when defining a subclass of RestrictedWrapper.
It will be replaced with a property. See the RestrictedWrapper
documentation for an example.
"""
def __new__(cls, name, from_str=None, to_str=None, allow_none=True):
"""Create a new RestrictedField placeholder.
The getter that will replace this returns (or applies the given to_str
function to) None for fields that do not exist in the underlying data
object.
:param field_name: The name of the deb822 field.
:param from_str: The function to apply for getters (default is to return
the string directly).
:param to_str: The function to apply for setters (default is to use the
value directly). If allow_none is True, this function may return
None, in which case the underlying key is deleted.
:param allow_none: Whether it is allowed to set the value to None
(which results in the underlying key being deleted).
"""
return super(RestrictedField, cls).__new__(
cls, name, from_str=from_str, to_str=to_str,
allow_none=allow_none)
@six.add_metaclass(_ClassInitMeta)
class RestrictedWrapper(object):
"""Base class to wrap a Deb822 object, restricting write access to some keys.
The underlying data is hidden internally. Subclasses may keep a reference
to the data before giving it to this class's constructor, if necessary, but
RestrictedProperty should cover most use-cases. The dump method from
Deb822 is directly proxied.
Typical usage:
class Foo(object):
def __init__(self, ...):
# ...
@staticmethod
def from_str(self, s):
# Parse s...
return Foo(...)
def to_str(self):
# Return in string format.
return ...
class MyClass(deb822.RestrictedWrapper):
def __init__(self):
data = deb822.Deb822()
data['Bar'] = 'baz'
super(MyClass, self).__init__(data)
foo = deb822.RestrictedProperty(
'Foo', from_str=Foo.from_str, to_str=Foo.to_str)
bar = deb822.RestrictedProperty('Bar', allow_none=False)
d = MyClass()
d['Bar'] # returns 'baz'
d['Bar'] = 'quux' # raises RestrictedFieldError
d.bar = 'quux'
d.bar # returns 'quux'
d['Bar'] # returns 'quux'
d.foo = Foo(...)
d['Foo'] # returns string representation of foo
"""
@classmethod
def _class_init(cls, new_attrs):
restricted_fields = []
for attr_name, val in new_attrs.items():
if isinstance(val, RestrictedField):
restricted_fields.append(val.name.lower())
cls.__init_restricted_field(attr_name, val)
cls.__restricted_fields = frozenset(restricted_fields)
@classmethod
def __init_restricted_field(cls, attr_name, field):
def getter(self):
val = self.__data.get(field.name)
if field.from_str is not None:
return field.from_str(val)
return val
def setter(self, val):
if val is not None and field.to_str is not None:
val = field.to_str(val)
if val is None:
if field.allow_none:
if field.name in self.__data:
del self.__data[field.name]
else:
raise TypeError('value must not be None')
else:
self.__data[field.name] = val
setattr(cls, attr_name, property(getter, setter, None, field.name))
def __init__(self, data):
"""Initializes the wrapper over 'data', a Deb822 object."""
super(RestrictedWrapper, self).__init__()
self.__data = data
def __getitem__(self, key):
return self.__data[key]
def __setitem__(self, key, value):
if key.lower() in self.__restricted_fields:
raise RestrictedFieldError(
'%s may not be modified directly; use the associated'
' property' % key)
self.__data[key] = value
def __delitem__(self, key):
if key.lower() in self.__restricted_fields:
raise RestrictedFieldError(
'%s may not be modified directly; use the associated'
' property' % key)
del self.__data[key]
def __iter__(self):
return iter(self.__data)
def __len__(self):
return len(self.__data)
def dump(self, *args, **kwargs):
"""Calls dump() on the underlying data object.
See Deb822.dump for more information.
"""
return self.__data.dump(*args, **kwargs)
class Removals(Deb822):
"""Represent an ftp-master removals.822 file
Removal of packages from the archive are recorded by ftp-masters.
See https://ftp-master.debian.org/#removed
Note: this API is experimental and backwards-incompatible changes might be
required in the future. Please use it and help us improve it!
"""
__sources_line_re = re.compile(r'\s*'
r'(?P<package>.+?)'
r'_'
r'(?P<version>[^\s]+)'
r'\s*'
)
__binaries_line_re = re.compile(r'\s*'
r'(?P<package>.+?)'
r'_'
r'(?P<version>[^\s]+)'
r'\s+'
r'\[(?P<archs>.+)\]'
)
@property
def date(self):
""" a datetime object for the removal action """
ts = email.utils.mktime_tz(email.utils.parsedate_tz(self['date']))
return datetime.datetime.fromtimestamp(ts)
@property
def bug(self):
""" list of bug numbers that had requested the package removal
The bug numbers are returned as integers.
Note: there is normally only one entry in this list but there may be
more than one.
"""
if 'bug' not in self:
return []
return [int(b) for b in self['bug'].split(",")]
@property
def also_wnpp(self):
""" list of WNPP bug numbers closed by the removal
The bug numbers are returned as integers.
"""
if 'also-wnpp' not in self:
return []
return [int(b) for b in self['also-wnpp'].split(" ")]
@property
def also_bugs(self):
""" list of bug numbers in the package closed by the removal
The bug numbers are returned as integers.
Removal of a package implicitly also closes all bugs associated with
the package.
"""
if 'also-bugs' not in self:
return []
return [int(b) for b in self['also-bugs'].split(" ")]
@property
def sources(self):
""" list of source packages that were removed
A list of dicts is returned, each dict has the form:
{
'source': 'some-package-name',
'version': '1.2.3-1'
}
Note: There may be no source packages removed at all if the removal is
only of a binary package. An empty list is returned in that case.
"""
if hasattr(self, '_sources'):
return self._sources
s = []
if 'sources' in self:
for line in self['sources'].splitlines():
matches = self.__sources_line_re.match(line)
if matches:
s.append({
'source': matches.group('package'),
'version': matches.group('version'),
})
self._sources = s
return s
@property
def binaries(self):
""" list of binary packages that were removed
A list of dicts is returned, each dict has the form:
{
'package': 'some-package-name',
'version': '1.2.3-1',
'architectures': set(['i386', 'amd64'])
}
"""
if hasattr(self, '_binaries'):
return self._binaries
b = []
if 'binaries' in self:
for line in self['binaries'].splitlines():
matches = self.__binaries_line_re.match(line)
if matches:
b.append({
'package': matches.group('package'),
'version': matches.group('version'),
'architectures':
set(matches.group('archs').split(', ')),
})
self._binaries = b
return b
class _CaseInsensitiveString(str):
"""Case insensitive string.
"""
def __new__(cls, str_):
s = str.__new__(cls, str_)
s.str_lower = str_.lower()
s.str_lower_hash = hash(s.str_lower)
return s
def __hash__(self):
return self.str_lower_hash
def __eq__(self, other):
return self.str_lower == other.lower()
def lower(self):
return self.str_lower
_strI = _CaseInsensitiveString