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- """Configuration file parser.
-
- A setup file consists of sections, lead by a "[section]" header,
- and followed by "name: value" entries, with continuations and such in
- the style of RFC 822.
-
- The option values can contain format strings which refer to other values in
- the same section, or values in a special [DEFAULT] section.
-
- For example:
-
- something: %(dir)s/whatever
-
- would resolve the "%(dir)s" to the value of dir. All reference
- expansions are done late, on demand.
-
- Intrinsic defaults can be specified by passing them into the
- ConfigParser constructor as a dictionary.
-
- class:
-
- ConfigParser -- responsible for for parsing a list of
- configuration files, and managing the parsed database.
-
- methods:
-
- __init__(defaults=None)
- create the parser and specify a dictionary of intrinsic defaults. The
- keys must be strings, the values must be appropriate for %()s string
- interpolation. Note that `__name__' is always an intrinsic default;
- it's value is the section's name.
-
- sections()
- return all the configuration section names, sans DEFAULT
-
- options(section)
- return list of configuration options for the named section
-
- read(filenames)
- read and parse the list of named configuration files
-
- get(section, option, raw=0, vars=None)
- return a string value for the named option. All % interpolations are
- expanded in the return values, based on the defaults passed into the
- constructor and the DEFAULT section. Additional substitutions may be
- provided using the `vars' argument, which must be a dictionary whose
- contents override any pre-existing defaults.
-
- getint(section, options)
- like get(), but convert value to an integer
-
- getfloat(section, options)
- like get(), but convert value to a float
-
- getboolean(section, options)
- like get(), but convert value to a boolean (currently defined as 0 or
- 1, only)
- """
-
- import sys
- import string
- import re
-
- DEFAULTSECT = "DEFAULT"
-
-
-
- # exception classes
- class Error:
- def __init__(self, msg=''):
- self._msg = msg
- def __repr__(self):
- return self._msg
-
- class NoSectionError(Error):
- def __init__(self, section):
- Error.__init__(self, 'No section: %s' % section)
- self.section = section
-
- class DuplicateSectionError(Error):
- def __init__(self, section):
- Error.__init__(self, "Section %s already exists" % section)
- self.section = section
-
- class NoOptionError(Error):
- def __init__(self, option, section):
- Error.__init__(self, "No option `%s' in section: %s" %
- (option, section))
- self.option = option
- self.section = section
-
- class InterpolationError(Error):
- def __init__(self, reference, option, section, rawval):
- Error.__init__(self,
- "Bad value substitution:\n"
- "\tsection: [%s]\n"
- "\toption : %s\n"
- "\tkey : %s\n"
- "\trawval : %s\n"
- % (section, option, reference, rawval))
- self.reference = reference
- self.option = option
- self.section = section
-
- class MissingSectionHeaderError(Error):
- def __init__(self, filename, lineno, line):
- Error.__init__(
- self,
- 'File contains no section headers.\nfile: %s, line: %d\n%s' %
- (filename, lineno, line))
- self.filename = filename
- self.lineno = lineno
- self.line = line
-
- class ParsingError(Error):
- def __init__(self, filename):
- Error.__init__(self, 'File contains parsing errors: %s' % filename)
- self.filename = filename
- self.errors = []
-
- def append(self, lineno, line):
- self.errors.append((lineno, line))
- self._msg = self._msg + '\n\t[line %2d]: %s' % (lineno, line)
-
-
-
- class ConfigParser:
- def __init__(self, defaults=None):
- self.__sections = {}
- if defaults is None:
- self.__defaults = {}
- else:
- self.__defaults = defaults
-
- def defaults(self):
- return self.__defaults
-
- def sections(self):
- """Return a list of section names, excluding [DEFAULT]"""
- # self.__sections will never have [DEFAULT] in it
- return self.__sections.keys()
-
- def add_section(self, section):
- """Create a new section in the configuration.
-
- Raise DuplicateSectionError if a section by the specified name
- already exists.
- """
- if self.__sections.has_key(section):
- raise DuplicateSectionError(section)
- self.__sections[section] = {}
-
- def has_section(self, section):
- """Indicate whether the named section is present in the configuration.
-
- The DEFAULT section is not acknowledged.
- """
- return self.__sections.has_key(section)
-
- def options(self, section):
- try:
- opts = self.__sections[section].copy()
- except KeyError:
- raise NoSectionError(section)
- opts.update(self.__defaults)
- return opts.keys()
-
- def read(self, filenames):
- """Read and parse a list of filenames."""
- if type(filenames) is type(''):
- filenames = [filenames]
- for file in filenames:
- try:
- fp = open(file, 'r')
- self.__read(fp)
- except IOError:
- pass
-
- def get(self, section, option, raw=0, vars=None):
- """Get an option value for a given section.
-
- All % interpolations are expanded in the return values, based on the
- defaults passed into the constructor, unless the optional argument
- `raw' is true. Additional substitutions may be provided using the
- `vars' argument, which must be a dictionary whose contents overrides
- any pre-existing defaults.
-
- The section DEFAULT is special.
- """
- try:
- sectdict = self.__sections[section].copy()
- except KeyError:
- if section == DEFAULTSECT:
- sectdict = {}
- else:
- raise NoSectionError(section)
- d = self.__defaults.copy()
- d.update(sectdict)
- # Update with the entry specific variables
- if vars:
- d.update(vars)
- option = string.lower(option)
- try:
- rawval = d[option]
- except KeyError:
- raise NoOptionError(option, section)
- # do the string interpolation
- if raw:
- return rawval
-
- value = rawval # Make it a pretty variable name
- depth = 0
- while depth < 10: # Loop through this until it's done
- depth = depth + 1
- if not string.find(value, "%("):
- try:
- value = value % d
- except KeyError, key:
- raise InterpolationError(key, option, section, rawval)
- else:
- return value
-
- def __get(self, section, conv, option):
- return conv(self.get(section, option))
-
- def getint(self, section, option):
- return self.__get(section, string.atoi, option)
-
- def getfloat(self, section, option):
- return self.__get(section, string.atof, option)
-
- def getboolean(self, section, option):
- v = self.get(section, option)
- val = string.atoi(v)
- if val not in (0, 1):
- raise ValueError, 'Not a boolean: %s' % v
- return val
-
- #
- # Regular expressions for parsing section headers and options. Note a
- # slight semantic change from the previous version, because of the use
- # of \w, _ is allowed in section header names.
- __SECTCRE = re.compile(
- r'\[' # [
- r'(?P<header>[-\w]+)' # `-', `_' or any alphanum
- r'\]' # ]
- )
- __OPTCRE = re.compile(
- r'(?P<option>[-.\w]+)' # - . _ alphanum
- r'[ \t]*[:=][ \t]*' # any number of space/tab,
- # followed by separator
- # (either : or =), followed
- # by any # space/tab
- r'(?P<value>.*)$' # everything up to eol
- )
-
- def __read(self, fp):
- """Parse a sectioned setup file.
-
- The sections in setup file contains a title line at the top,
- indicated by a name in square brackets (`[]'), plus key/value
- options lines, indicated by `name: value' format lines.
- Continuation are represented by an embedded newline then
- leading whitespace. Blank lines, lines beginning with a '#',
- and just about everything else is ignored.
- """
- cursect = None # None, or a dictionary
- optname = None
- lineno = 0
- e = None # None, or an exception
- while 1:
- line = fp.readline()
- if not line:
- break
- lineno = lineno + 1
- # comment or blank line?
- if string.strip(line) == '' or line[0] in '#;':
- continue
- if string.lower(string.split(line)[0]) == 'rem' \
- and line[0] == "r": # no leading whitespace
- continue
- # continuation line?
- if line[0] in ' \t' and cursect is not None and optname:
- value = string.strip(line)
- if value:
- cursect[optname] = cursect[optname] + '\n ' + value
- # a section header or option header?
- else:
- # is it a section header?
- mo = self.__SECTCRE.match(line)
- if mo:
- sectname = mo.group('header')
- if self.__sections.has_key(sectname):
- cursect = self.__sections[sectname]
- elif sectname == DEFAULTSECT:
- cursect = self.__defaults
- else:
- cursect = {'__name__': sectname}
- self.__sections[sectname] = cursect
- # So sections can't start with a continuation line
- optname = None
- # no section header in the file?
- elif cursect is None:
- raise MissingSectionHeaderError(fp.name, lineno, `line`)
- # an option line?
- else:
- mo = self.__OPTCRE.match(line)
- if mo:
- optname, optval = mo.group('option', 'value')
- optname = string.lower(optname)
- optval = string.strip(optval)
- # allow empty values
- if optval == '""':
- optval = ''
- cursect[optname] = optval
- else:
- # a non-fatal parsing error occurred. set up the
- # exception but keep going. the exception will be
- # raised at the end of the file and will contain a
- # list of all bogus lines
- if not e:
- e = ParsingError(fp.name)
- e.append(lineno, `line`)
- # if any parsing errors occurred, raise an exception
- if e:
- raise e
-