"""Utlity class wrapping base-class methods into decorators that assure read-only properties"""

def __new__(metacls, name, bases, clsdict):

"""

kmm = '_mutating_methods_'

if kmm in clsdict:

mutating_methods = clsdict[kmm]

for base in bases:

methods = (t for t in inspect.getmembers(base, inspect.isroutine) if not t[0].startswith("_"))

for name, method in methods:

if name in clsdict:

continue

method_with_values = needs_values(method)

if name in mutating_methods:

method_with_values = set_dirty_and_flush_changes(method_with_values)

# END mutating methods handling

clsdict[name] = method_with_values

# END for each name/method pair

# END for each base

# END if mutating methods configuration is set

new_type = super(MetaParserBuilder, metacls).__new__(metacls, name, bases, clsdict)

"""Returns method assuring we read values (on demand) before we try to access them"""

def assure_data_present(self, *args, **kwargs):

self.read()

return func(self, *args, **kwargs)

# END wrapper method

assure_data_present.__name__ = func.__name__

"""Return method that checks whether given non constant function may be called.

def flush_changes(self, *args, **kwargs):

rval = non_const_func(self, *args, **kwargs)

self._dirty = True

self.write()

return rval

# END wrapper method

flush_changes.__name__ = non_const_func.__name__

"""Constrains a ConfigParser to only option commands which are constrained to

__slots__ = ("_config", "_section_name")

_valid_attrs_ = ("get_value", "set_value", "get", "set", "getint", "getfloat", "getboolean", "has_option",

"remove_section", "remove_option", "options")

def __init__(self, config, section):

self._config = config

self._section_name = section

def __del__(self):

# Yes, for some reason, we have to call it explicitly for it to work in PY3 !

# Apparently __del__ doesn't get call anymore if refcount becomes 0

# Ridiculous ... .

self._config.release()

def __getattr__(self, attr):

if attr in self._valid_attrs_:

return lambda *args, **kwargs: self._call_config(attr, *args, **kwargs)

return super(SectionConstraint, self).__getattribute__(attr)

def _call_config(self, method, *args, **kwargs):

"""Call the configuration at the given method which must take a section name

return getattr(self._config, method)(self._section_name, *args, **kwargs)

@property

def config(self):

"""return: Configparser instance we constrain"""

return self._config

def release(self):

"""Equivalent to GitConfigParser.release(), which is called on our underlying parser instance"""

"""Implements specifics required to read git style configuration files.

#{ Configuration

# The lock type determines the type of lock to use in new configuration readers.

# They must be compatible to the LockFile interface.

# A suitable alternative would be the BlockingLockFile

t_lock = LockFile

re_comment = re.compile('^\s*[#;]')

#} END configuration

OPTCRE = re.compile(

r'\s*(?P<option>[^:=\s][^:=]*)' # very permissive, incuding leading whitespace

r'\s*(?P<vi>[:=])\s*' # any number of space/tab,

# followed by separator

# (either : or =), followed

# by any # space/tab

r'(?P<value>.*)$' # everything up to eol

)

# list of RawConfigParser methods able to change the instance

_mutating_methods_ = ("add_section", "remove_section", "remove_option", "set")

def __init__(self, file_or_files, read_only=True, merge_includes=True):

"""Initialize a configuration reader to read the given file_or_files and to

cp.RawConfigParser.__init__(self, dict_type=OrderedDict)

# Used in python 3, needs to stay in sync with sections for underlying implementation to work

if not hasattr(self, '_proxies'):

self._proxies = self._dict()

self._file_or_files = file_or_files

self._read_only = read_only

self._dirty = False

self._is_initialized = False

self._merge_includes = merge_includes

self._lock = None

if not read_only:

if isinstance(file_or_files, (tuple, list)):

raise ValueError(

"Write-ConfigParsers can operate on a single file only, multiple files have been passed")

# END single file check

if not isinstance(file_or_files, string_types):

file_or_files = file_or_files.name

# END get filename from handle/stream

# initialize lock base - we want to write

self._lock = self.t_lock(file_or_files)

self._lock._obtain_lock()

# END read-only check

def __del__(self):

"""Write pending changes if required and release locks"""

# NOTE: only consistent in PY2

self.release()

def release(self):

"""Flush changes and release the configuration write lock. This instance must not be used anymore afterwards.

# checking for the lock here makes sure we do not raise during write()

# in case an invalid parser was created who could not get a lock

if self.read_only or (self._lock and not self._lock._has_lock()):

return

try:

try:

self.write()

except IOError:

log.error("Exception during destruction of GitConfigParser", exc_info=True)

except ReferenceError:

# This happens in PY3 ... and usually means that some state cannot be written

# as the sections dict cannot be iterated

# Usually when shutting down the interpreter, don'y know how to fix this

pass

finally:

self._lock._release_lock()

def optionxform(self, optionstr):

"""Do not transform options in any way when writing"""

return optionstr

def _read(self, fp, fpname):

"""A direct copy of the py2.4 version of the super class's _read method

cursect = None # None, or a dictionary

optname = None

lineno = 0

is_multi_line = False

e = None # None, or an exception

def string_decode(v):

if v[-1] == '\\':

v = v[:-1]

# end cut trailing escapes to prevent decode error

if PY3:

return v.encode(defenc).decode('unicode_escape')

else:

return v.decode('string_escape')

# end

# end

while True:

# we assume to read binary !

line = fp.readline().decode(defenc)

if not line:

break

lineno = lineno + 1

# comment or blank line?

if line.strip() == '' or self.re_comment.match(line):

continue

if line.split(None, 1)[0].lower() == 'rem' and line[0] in "rR":

# no leading whitespace

continue

# is it a section header?

mo = self.SECTCRE.match(line.strip())

if not is_multi_line and mo:

sectname = mo.group('header').strip()

if sectname in self._sections:

cursect = self._sections[sectname]

elif sectname == cp.DEFAULTSECT:

cursect = self._defaults

else:

cursect = self._dict((('__name__', sectname),))

self._sections[sectname] = cursect

self._proxies[sectname] = None

# So sections can't start with a continuation line

optname = None

# no section header in the file?

elif cursect is None:

raise cp.MissingSectionHeaderError(fpname, lineno, line)

# an option line?

elif not is_multi_line:

mo = self.OPTCRE.match(line)

if mo:

# We might just have handled the last line, which could contain a quotation we want to remove

optname, vi, optval = mo.group('option', 'vi', 'value')

if vi in ('=', ':') and ';' in optval and not optval.strip().startswith('"'):

pos = optval.find(';')

if pos != -1 and optval[pos - 1].isspace():

optval = optval[:pos]

optval = optval.strip()

if optval == '""':

optval = ''

# end handle empty string

optname = self.optionxform(optname.rstrip())

if len(optval) > 1 and optval[0] == '"' and optval[-1] != '"':

is_multi_line = True

optval = string_decode(optval[1:])

# end handle multi-line

cursect[optname] = optval

else:

if not e:

e = cp.ParsingError(fpname)

e.append(lineno, repr(line))

continue

else:

line = line.rstrip()

if line.endswith('"'):

is_multi_line = False

line = line[:-1]

# end handle quotations

cursect[optname] += string_decode(line)

# END parse section or option

# END while reading

# if any parsing errors occurred, raise an exception

if e:

raise e

def _has_includes(self):

return self._merge_includes and self.has_section('include')

def read(self):

"""Reads the data stored in the files we have been initialized with. It will

if self._is_initialized:

return

self._is_initialized = True

if not isinstance(self._file_or_files, (tuple, list)):

files_to_read = [self._file_or_files]

else:

files_to_read = list(self._file_or_files)

# end assure we have a copy of the paths to handle

seen = set(files_to_read)

num_read_include_files = 0

while files_to_read:

file_path = files_to_read.pop(0)

fp = file_path

close_fp = False

# assume a path if it is not a file-object

if not hasattr(fp, "seek"):

try:

fp = open(file_path, 'rb')

close_fp = True

except IOError:

continue

# END fp handling

try:

self._read(fp, fp.name)

finally:

if close_fp:

fp.close()

# END read-handling

# Read includes and append those that we didn't handle yet

# We expect all paths to be normalized and absolute (and will assure that is the case)

if self._has_includes():

for _, include_path in self.items('include'):

if not os.path.isabs(include_path):

if not close_fp:

continue

# end ignore relative paths if we don't know the configuration file path

assert os.path.isabs(file_path), "Need absolute paths to be sure our cycle checks will work"

include_path = os.path.join(os.path.dirname(file_path), include_path)

# end make include path absolute

include_path = os.path.normpath(include_path)

if include_path in seen or not os.access(include_path, os.R_OK):

continue

seen.add(include_path)

files_to_read.append(include_path)

num_read_include_files += 1

# each include path in configuration file

# end handle includes

# END for each file object to read

# If there was no file included, we can safely write back (potentially) the configuration file

# without altering it's meaning

if num_read_include_files == 0:

self._merge_includes = False

# end

def _write(self, fp):

"""Write an .ini-format representation of the configuration state in

def write_section(name, section_dict):

fp.write(("[%s]\n" % name).encode(defenc))

for (key, value) in section_dict.items():

if key != "__name__":

fp.write(("\t%s = %s\n" % (key, self._value_to_string(value).replace('\n', '\n\t'))).encode(defenc))

# END if key is not __name__

# END section writing

if self._defaults:

write_section(cp.DEFAULTSECT, self._defaults)

for name, value in self._sections.items():

write_section(name, value)

def items(self, section_name):

""":return: list((option, value), ...) pairs of all items in the given section"""

return [(k, v) for k, v in super(GitConfigParser, self).items(section_name) if k != '__name__']

@needs_values

def write(self):

"""Write changes to our file, if there are changes at all

self._assure_writable("write")

if not self._dirty:

return

if isinstance(self._file_or_files, (list, tuple)):

raise AssertionError("Cannot write back if there is not exactly a single file to write to, have %i files"

% len(self._file_or_files))

# end assert multiple files

if self._has_includes():

log.debug("Skipping write-back of confiuration file as include files were merged in." +

"Set merge_includes=False to prevent this.")

return

# end

fp = self._file_or_files

close_fp = False

# we have a physical file on disk, so get a lock

if isinstance(fp, string_types + (FileType, )):

self._lock._obtain_lock()

# END get lock for physical files

if not hasattr(fp, "seek"):

fp = open(self._file_or_files, "wb")

close_fp = True

else:

fp.seek(0)

# make sure we do not overwrite into an existing file

if hasattr(fp, 'truncate'):

fp.truncate()

# END

# END handle stream or file

# WRITE DATA

try:

self._write(fp)

finally:

if close_fp:

fp.close()

# END data writing

# we do not release the lock - it will be done automatically once the

# instance vanishes

def _assure_writable(self, method_name):

if self.read_only:

raise IOError("Cannot execute non-constant method %s.%s" % (self, method_name))

def add_section(self, section):

"""Assures added options will stay in order"""

return super(GitConfigParser, self).add_section(section)

@property

def read_only(self):

""":return: True if this instance may change the configuration file"""

return self._read_only

def get_value(self, section, option, default=None):

"""

try:

valuestr = self.get(section, option)

except Exception:

if default is not None:

return default

raise

types = (int, float)

for numtype in types:

try:

val = numtype(valuestr)

# truncated value ?

if val != float(valuestr):

continue

return val

except (ValueError, TypeError):

continue

# END for each numeric type

# try boolean values as git uses them

vl = valuestr.lower()

if vl == 'false':

return False

if vl == 'true':

return True

if not isinstance(valuestr, string_types):

raise TypeError("Invalid value type: only int, long, float and str are allowed", valuestr)

return valuestr

def _value_to_string(self, value):

if isinstance(value, (int, float, bool)):

return str(value)

return force_text(value)

@needs_values

@set_dirty_and_flush_changes

def set_value(self, section, option, value):

"""Sets the given option in section to the given value.

if not self.has_section(section):

self.add_section(section)

self.set(section, option, self._value_to_string(value))

return self

def rename_section(self, section, new_name):

"""rename the given section to new_name

if not self.has_section(section):

raise ValueError("Source section '%s' doesn't exist" % section)

if self.has_section(new_name):

raise ValueError("Destination section '%s' already exists" % new_name)

super(GitConfigParser, self).add_section(new_name)

for k, v in self.items(section):

self.set(new_name, k, self._value_to_string(v))

# end for each value to copy

# This call writes back the changes, which is why we don't have the respective decorator

self.remove_section(section)