source file: /System/Library/Frameworks/Python.framework/Versions/2.3/lib/python2.3/ConfigParser.py
file stats: 312 lines, 61 executed: 19.6% covered
   1. """Configuration file parser.
   2. 
   3. A setup file consists of sections, lead by a "[section]" header,
   4. and followed by "name: value" entries, with continuations and such in
   5. the style of RFC 822.
   6. 
   7. The option values can contain format strings which refer to other values in
   8. the same section, or values in a special [DEFAULT] section.
   9. 
  10. For example:
  11. 
  12.     something: %(dir)s/whatever
  13. 
  14. would resolve the "%(dir)s" to the value of dir.  All reference
  15. expansions are done late, on demand.
  16. 
  17. Intrinsic defaults can be specified by passing them into the
  18. ConfigParser constructor as a dictionary.
  19. 
  20. class:
  21. 
  22. ConfigParser -- responsible for parsing a list of
  23.                 configuration files, and managing the parsed database.
  24. 
  25.     methods:
  26. 
  27.     __init__(defaults=None)
  28.         create the parser and specify a dictionary of intrinsic defaults.  The
  29.         keys must be strings, the values must be appropriate for %()s string
  30.         interpolation.  Note that `__name__' is always an intrinsic default;
  31.         it's value is the section's name.
  32. 
  33.     sections()
  34.         return all the configuration section names, sans DEFAULT
  35. 
  36.     has_section(section)
  37.         return whether the given section exists
  38. 
  39.     has_option(section, option)
  40.         return whether the given option exists in the given section
  41. 
  42.     options(section)
  43.         return list of configuration options for the named section
  44. 
  45.     read(filenames)
  46.         read and parse the list of named configuration files, given by
  47.         name.  A single filename is also allowed.  Non-existing files
  48.         are ignored.
  49. 
  50.     readfp(fp, filename=None)
  51.         read and parse one configuration file, given as a file object.
  52.         The filename defaults to fp.name; it is only used in error
  53.         messages (if fp has no `name' attribute, the string `<???>' is used).
  54. 
  55.     get(section, option, raw=False, vars=None)
  56.         return a string value for the named option.  All % interpolations are
  57.         expanded in the return values, based on the defaults passed into the
  58.         constructor and the DEFAULT section.  Additional substitutions may be
  59.         provided using the `vars' argument, which must be a dictionary whose
  60.         contents override any pre-existing defaults.
  61. 
  62.     getint(section, options)
  63.         like get(), but convert value to an integer
  64. 
  65.     getfloat(section, options)
  66.         like get(), but convert value to a float
  67. 
  68.     getboolean(section, options)
  69.         like get(), but convert value to a boolean (currently case
  70.         insensitively defined as 0, false, no, off for False, and 1, true,
  71.         yes, on for True).  Returns False or True.
  72. 
  73.     items(section, raw=False, vars=None)
  74.         return a list of tuples with (name, value) for each option
  75.         in the section.
  76. 
  77.     remove_section(section)
  78.         remove the given file section and all its options
  79. 
  80.     remove_option(section, option)
  81.         remove the given option from the given section
  82. 
  83.     set(section, option, value)
  84.         set the given option
  85. 
  86.     write(fp)
  87.         write the configuration state in .ini format
  88. """
  89. 
  90. import re
  91. 
  92. __all__ = ["NoSectionError", "DuplicateSectionError", "NoOptionError",
  93.            "InterpolationError", "InterpolationDepthError",
  94.            "InterpolationSyntaxError", "ParsingError",
  95.            "MissingSectionHeaderError", "ConfigParser", "SafeConfigParser",
  96.            "DEFAULTSECT", "MAX_INTERPOLATION_DEPTH"]
  97. 
  98. DEFAULTSECT = "DEFAULT"
  99. 
 100. MAX_INTERPOLATION_DEPTH = 10
 101. 
 102. 
 103. 
 104. # exception classes
 105. class Error(Exception):
 106.     """Base class for ConfigParser exceptions."""
 107. 
 108.     def __init__(self, msg=''):
 109.         self.message = msg
 110.         Exception.__init__(self, msg)
 111. 
 112.     def __repr__(self):
 113.         return self.message
 114. 
 115.     __str__ = __repr__
 116. 
 117. class NoSectionError(Error):
 118.     """Raised when no section matches a requested option."""
 119. 
 120.     def __init__(self, section):
 121.         Error.__init__(self, 'No section: ' + `section`)
 122.         self.section = section
 123. 
 124. class DuplicateSectionError(Error):
 125.     """Raised when a section is multiply-created."""
 126. 
 127.     def __init__(self, section):
 128.         Error.__init__(self, "Section %r already exists" % section)
 129.         self.section = section
 130. 
 131. class NoOptionError(Error):
 132.     """A requested option was not found."""
 133. 
 134.     def __init__(self, option, section):
 135.         Error.__init__(self, "No option %r in section: %r" %
 136.                        (option, section))
 137.         self.option = option
 138.         self.section = section
 139. 
 140. class InterpolationError(Error):
 141.     """Base class for interpolation-related exceptions."""
 142. 
 143.     def __init__(self, option, section, msg):
 144.         Error.__init__(self, msg)
 145.         self.option = option
 146.         self.section = section
 147. 
 148. class InterpolationMissingOptionError(InterpolationError):
 149.     """A string substitution required a setting which was not available."""
 150. 
 151.     def __init__(self, option, section, rawval, reference):
 152.         msg = ("Bad value substitution:\n"
 153.                "\tsection: [%s]\n"
 154.                "\toption : %s\n"
 155.                "\tkey    : %s\n"
 156.                "\trawval : %s\n"
 157.                % (section, option, reference, rawval))
 158.         InterpolationError.__init__(self, option, section, msg)
 159.         self.reference = reference
 160. 
 161. class InterpolationSyntaxError(InterpolationError):
 162.     """Raised when the source text into which substitutions are made
 163.     does not conform to the required syntax."""
 164. 
 165. class InterpolationDepthError(InterpolationError):
 166.     """Raised when substitutions are nested too deeply."""
 167. 
 168.     def __init__(self, option, section, rawval):
 169.         msg = ("Value interpolation too deeply recursive:\n"
 170.                "\tsection: [%s]\n"
 171.                "\toption : %s\n"
 172.                "\trawval : %s\n"
 173.                % (section, option, rawval))
 174.         InterpolationError.__init__(self, option, section, msg)
 175. 
 176. class ParsingError(Error):
 177.     """Raised when a configuration file does not follow legal syntax."""
 178. 
 179.     def __init__(self, filename):
 180.         Error.__init__(self, 'File contains parsing errors: %s' % filename)
 181.         self.filename = filename
 182.         self.errors = []
 183. 
 184.     def append(self, lineno, line):
 185.         self.errors.append((lineno, line))
 186.         self.message += '\n\t[line %2d]: %s' % (lineno, line)
 187. 
 188. class MissingSectionHeaderError(ParsingError):
 189.     """Raised when a key-value pair is found before any section header."""
 190. 
 191.     def __init__(self, filename, lineno, line):
 192.         Error.__init__(
 193.             self,
 194.             'File contains no section headers.\nfile: %s, line: %d\n%s' %
 195.             (filename, lineno, line))
 196.         self.filename = filename
 197.         self.lineno = lineno
 198.         self.line = line
 199. 
 200. 
 201. 
 202. class RawConfigParser:
 203.     def __init__(self, defaults=None):
 204.         self._sections = {}
 205.         if defaults is None:
 206.             self._defaults = {}
 207.         else:
 208.             self._defaults = defaults
 209. 
 210.     def defaults(self):
 211.         return self._defaults
 212. 
 213.     def sections(self):
 214.         """Return a list of section names, excluding [DEFAULT]"""
 215.         # self._sections will never have [DEFAULT] in it
 216.         return self._sections.keys()
 217. 
 218.     def add_section(self, section):
 219.         """Create a new section in the configuration.
 220. 
 221.         Raise DuplicateSectionError if a section by the specified name
 222.         already exists.
 223.         """
 224.         if section in self._sections:
 225.             raise DuplicateSectionError(section)
 226.         self._sections[section] = {}
 227. 
 228.     def has_section(self, section):
 229.         """Indicate whether the named section is present in the configuration.
 230. 
 231.         The DEFAULT section is not acknowledged.
 232.         """
 233.         return section in self._sections
 234. 
 235.     def options(self, section):
 236.         """Return a list of option names for the given section name."""
 237.         try:
 238.             opts = self._sections[section].copy()
 239.         except KeyError:
 240.             raise NoSectionError(section)
 241.         opts.update(self._defaults)
 242.         if '__name__' in opts:
 243.             del opts['__name__']
 244.         return opts.keys()
 245. 
 246.     def read(self, filenames):
 247.         """Read and parse a filename or a list of filenames.
 248. 
 249.         Files that cannot be opened are silently ignored; this is
 250.         designed so that you can specify a list of potential
 251.         configuration file locations (e.g. current directory, user's
 252.         home directory, systemwide directory), and all existing
 253.         configuration files in the list will be read.  A single
 254.         filename may also be given.
 255.         """
 256.         if isinstance(filenames, basestring):
 257.             filenames = [filenames]
 258.         for filename in filenames:
 259.             try:
 260.                 fp = open(filename)
 261.             except IOError:
 262.                 continue
 263.             self._read(fp, filename)
 264.             fp.close()
 265. 
 266.     def readfp(self, fp, filename=None):
 267.         """Like read() but the argument must be a file-like object.
 268. 
 269.         The `fp' argument must have a `readline' method.  Optional
 270.         second argument is the `filename', which if not given, is
 271.         taken from fp.name.  If fp has no `name' attribute, `<???>' is
 272.         used.
 273. 
 274.         """
 275.         if filename is None:
 276.             try:
 277.                 filename = fp.name
 278.             except AttributeError:
 279.                 filename = '<???>'
 280.         self._read(fp, filename)
 281. 
 282.     def get(self, section, option):
 283.         opt = self.optionxform(option)
 284.         if section not in self._sections:
 285.             if section != DEFAULTSECT:
 286.                 raise NoSectionError(section)
 287.             if opt in self._defaults:
 288.                 return self._defaults[opt]
 289.             else:
 290.                 raise NoOptionError(option, section)
 291.         elif opt in self._sections[section]:
 292.             return self._sections[section][opt]
 293.         elif opt in self._defaults:
 294.             return self._defaults[opt]
 295.         else:
 296.             raise NoOptionError(option, section)
 297. 
 298.     def items(self, section):
 299.         try:
 300.             d2 = self._sections[section]
 301.         except KeyError:
 302.             if section != DEFAULTSECT:
 303.                 raise NoSectionError(section)
 304.             d2 = {}
 305.         d = self._defaults.copy()
 306.         d.update(d2)
 307.         if "__name__" in d:
 308.             del d["__name__"]
 309.         return d.items()
 310. 
 311.     def _get(self, section, conv, option):
 312.         return conv(self.get(section, option))
 313. 
 314.     def getint(self, section, option):
 315.         return self._get(section, int, option)
 316. 
 317.     def getfloat(self, section, option):
 318.         return self._get(section, float, option)
 319. 
 320.     _boolean_states = {'1': True, 'yes': True, 'true': True, 'on': True,
 321.                        '0': False, 'no': False, 'false': False, 'off': False}
 322. 
 323.     def getboolean(self, section, option):
 324.         v = self.get(section, option)
 325.         if v.lower() not in self._boolean_states:
 326.             raise ValueError, 'Not a boolean: %s' % v
 327.         return self._boolean_states[v.lower()]
 328. 
 329.     def optionxform(self, optionstr):
 330.         return optionstr.lower()
 331. 
 332.     def has_option(self, section, option):
 333.         """Check for the existence of a given option in a given section."""
 334.         if not section or section == DEFAULTSECT:
 335.             option = self.optionxform(option)
 336.             return option in self._defaults
 337.         elif section not in self._sections:
 338.             return False
 339.         else:
 340.             option = self.optionxform(option)
 341.             return (option in self._sections[section]
 342.                     or option in self._defaults)
 343. 
 344.     def set(self, section, option, value):
 345.         """Set an option."""
 346.         if not section or section == DEFAULTSECT:
 347.             sectdict = self._defaults
 348.         else:
 349.             try:
 350.                 sectdict = self._sections[section]
 351.             except KeyError:
 352.                 raise NoSectionError(section)
 353.         sectdict[self.optionxform(option)] = value
 354. 
 355.     def write(self, fp):
 356.         """Write an .ini-format representation of the configuration state."""
 357.         if self._defaults:
 358.             fp.write("[%s]\n" % DEFAULTSECT)
 359.             for (key, value) in self._defaults.items():
 360.                 fp.write("%s = %s\n" % (key, str(value).replace('\n', '\n\t')))
 361.             fp.write("\n")
 362.         for section in self._sections:
 363.             fp.write("[%s]\n" % section)
 364.             for (key, value) in self._sections[section].items():
 365.                 if key != "__name__":
 366.                     fp.write("%s = %s\n" %
 367.                              (key, str(value).replace('\n', '\n\t')))
 368.             fp.write("\n")
 369. 
 370.     def remove_option(self, section, option):
 371.         """Remove an option."""
 372.         if not section or section == DEFAULTSECT:
 373.             sectdict = self._defaults
 374.         else:
 375.             try:
 376.                 sectdict = self._sections[section]
 377.             except KeyError:
 378.                 raise NoSectionError(section)
 379.         option = self.optionxform(option)
 380.         existed = option in sectdict
 381.         if existed:
 382.             del sectdict[option]
 383.         return existed
 384. 
 385.     def remove_section(self, section):
 386.         """Remove a file section."""
 387.         existed = section in self._sections
 388.         if existed:
 389.             del self._sections[section]
 390.         return existed
 391. 
 392.     #
 393.     # Regular expressions for parsing section headers and options.
 394.     #
 395.     SECTCRE = re.compile(
 396.         r'\['                                 # [
 397.         r'(?P<header>[^]]+)'                  # very permissive!
 398.         r'\]'                                 # ]
 399.         )
 400.     OPTCRE = re.compile(
 401.         r'(?P<option>[^:=\s][^:=]*)'          # very permissive!
 402.         r'\s*(?P<vi>[:=])\s*'                 # any number of space/tab,
 403.                                               # followed by separator
 404.                                               # (either : or =), followed
 405.                                               # by any # space/tab
 406.         r'(?P<value>.*)$'                     # everything up to eol
 407.         )
 408. 
 409.     def _read(self, fp, fpname):
 410.         """Parse a sectioned setup file.
 411. 
 412.         The sections in setup file contains a title line at the top,
 413.         indicated by a name in square brackets (`[]'), plus key/value
 414.         options lines, indicated by `name: value' format lines.
 415.         Continuations are represented by an embedded newline then
 416.         leading whitespace.  Blank lines, lines beginning with a '#',
 417.         and just about everything else are ignored.
 418.         """
 419.         cursect = None                            # None, or a dictionary
 420.         optname = None
 421.         lineno = 0
 422.         e = None                                  # None, or an exception
 423.         while True:
 424.             line = fp.readline()
 425.             if not line:
 426.                 break
 427.             lineno = lineno + 1
 428.             # comment or blank line?
 429.             if line.strip() == '' or line[0] in '#;':
 430.                 continue
 431.             if line.split(None, 1)[0].lower() == 'rem' and line[0] in "rR":
 432.                 # no leading whitespace
 433.                 continue
 434.             # continuation line?
 435.             if line[0].isspace() and cursect is not None and optname:
 436.                 value = line.strip()
 437.                 if value:
 438.                     cursect[optname] = "%s\n%s" % (cursect[optname], value)
 439.             # a section header or option header?
 440.             else:
 441.                 # is it a section header?
 442.                 mo = self.SECTCRE.match(line)
 443.                 if mo:
 444.                     sectname = mo.group('header')
 445.                     if sectname in self._sections:
 446.                         cursect = self._sections[sectname]
 447.                     elif sectname == DEFAULTSECT:
 448.                         cursect = self._defaults
 449.                     else:
 450.                         cursect = {'__name__': sectname}
 451.                         self._sections[sectname] = cursect
 452.                     # So sections can't start with a continuation line
 453.                     optname = None
 454.                 # no section header in the file?
 455.                 elif cursect is None:
 456.                     raise MissingSectionHeaderError(fpname, lineno, `line`)
 457.                 # an option line?
 458.                 else:
 459.                     mo = self.OPTCRE.match(line)
 460.                     if mo:
 461.                         optname, vi, optval = mo.group('option', 'vi', 'value')
 462.                         if vi in ('=', ':') and ';' in optval:
 463.                             # ';' is a comment delimiter only if it follows
 464.                             # a spacing character
 465.                             pos = optval.find(';')
 466.                             if pos != -1 and optval[pos-1].isspace():
 467.                                 optval = optval[:pos]
 468.                         optval = optval.strip()
 469.                         # allow empty values
 470.                         if optval == '""':
 471.                             optval = ''
 472.                         optname = self.optionxform(optname.rstrip())
 473.                         cursect[optname] = optval
 474.                     else:
 475.                         # a non-fatal parsing error occurred.  set up the
 476.                         # exception but keep going. the exception will be
 477.                         # raised at the end of the file and will contain a
 478.                         # list of all bogus lines
 479.                         if not e:
 480.                             e = ParsingError(fpname)
 481.                         e.append(lineno, `line`)
 482.         # if any parsing errors occurred, raise an exception
 483.         if e:
 484.             raise e
 485. 
 486. 
 487. class ConfigParser(RawConfigParser):
 488. 
 489.     def get(self, section, option, raw=False, vars=None):
 490.         """Get an option value for a given section.
 491. 
 492.         All % interpolations are expanded in the return values, based on the
 493.         defaults passed into the constructor, unless the optional argument
 494.         `raw' is true.  Additional substitutions may be provided using the
 495.         `vars' argument, which must be a dictionary whose contents overrides
 496.         any pre-existing defaults.
 497. 
 498.         The section DEFAULT is special.
 499.         """
 500.         d = self._defaults.copy()
 501.         try:
 502.             d.update(self._sections[section])
 503.         except KeyError:
 504.             if section != DEFAULTSECT:
 505.                 raise NoSectionError(section)
 506.         # Update with the entry specific variables
 507.         if vars is not None:
 508.             d.update(vars)
 509.         option = self.optionxform(option)
 510.         try:
 511.             value = d[option]
 512.         except KeyError:
 513.             raise NoOptionError(option, section)
 514. 
 515.         if raw:
 516.             return value
 517.         else:
 518.             return self._interpolate(section, option, value, d)
 519. 
 520.     def items(self, section, raw=False, vars=None):
 521.         """Return a list of tuples with (name, value) for each option
 522.         in the section.
 523. 
 524.         All % interpolations are expanded in the return values, based on the
 525.         defaults passed into the constructor, unless the optional argument
 526.         `raw' is true.  Additional substitutions may be provided using the
 527.         `vars' argument, which must be a dictionary whose contents overrides
 528.         any pre-existing defaults.
 529. 
 530.         The section DEFAULT is special.
 531.         """
 532.         d = self._defaults.copy()
 533.         try:
 534.             d.update(self._sections[section])
 535.         except KeyError:
 536.             if section != DEFAULTSECT:
 537.                 raise NoSectionError(section)
 538.         # Update with the entry specific variables
 539.         if vars:
 540.             d.update(vars)
 541.         options = d.keys()
 542.         if "__name__" in options:
 543.             options.remove("__name__")
 544.         if raw:
 545.             return [(option, d[option])
 546.                     for option in options]
 547.         else:
 548.             return [(option, self._interpolate(section, option, d[option], d))
 549.                     for option in options]
 550. 
 551.     def _interpolate(self, section, option, rawval, vars):
 552.         # do the string interpolation
 553.         value = rawval
 554.         depth = MAX_INTERPOLATION_DEPTH
 555.         while depth:                    # Loop through this until it's done
 556.             depth -= 1
 557.             if value.find("%(") != -1:
 558.                 try:
 559.                     value = value % vars
 560.                 except KeyError, e:
 561.                     raise InterpolationMissingOptionError(
 562.                         option, section, rawval, e[0])
 563.             else:
 564.                 break
 565.         if value.find("%(") != -1:
 566.             raise InterpolationDepthError(option, section, rawval)
 567.         return value
 568. 
 569. 
 570. class SafeConfigParser(ConfigParser):
 571. 
 572.     def _interpolate(self, section, option, rawval, vars):
 573.         # do the string interpolation
 574.         L = []
 575.         self._interpolate_some(option, L, rawval, section, vars, 1)
 576.         return ''.join(L)
 577. 
 578.     _interpvar_match = re.compile(r"%\(([^)]+)\)s").match
 579. 
 580.     def _interpolate_some(self, option, accum, rest, section, map, depth):
 581.         if depth > MAX_INTERPOLATION_DEPTH:
 582.             raise InterpolationDepthError(option, section, rest)
 583.         while rest:
 584.             p = rest.find("%")
 585.             if p < 0:
 586.                 accum.append(rest)
 587.                 return
 588.             if p > 0:
 589.                 accum.append(rest[:p])
 590.                 rest = rest[p:]
 591.             # p is no longer used
 592.             c = rest[1:2]
 593.             if c == "%":
 594.                 accum.append("%")
 595.                 rest = rest[2:]
 596.             elif c == "(":
 597.                 m = self._interpvar_match(rest)
 598.                 if m is None:
 599.                     raise InterpolationSyntaxError(option, section,
 600.                         "bad interpolation variable reference %r" % rest)
 601.                 var = m.group(1)
 602.                 rest = rest[m.end():]
 603.                 try:
 604.                     v = map[var]
 605.                 except KeyError:
 606.                     raise InterpolationMissingOptionError(
 607.                         option, section, rest, var)
 608.                 if "%" in v:
 609.                     self._interpolate_some(option, accum, v,
 610.                                            section, map, depth + 1)
 611.                 else:
 612.                     accum.append(v)
 613.             else:
 614.                 raise InterpolationSyntaxError(
 615.                     option, section,
 616.                     "'%' must be followed by '%' or '(', found: " + `rest`)