optionsclass.py

用python实现的邮件过滤器

                return False
            raise TypeError, self.name + " must be True or False"
        if self.multiple_values_allowed():
            # This will fall apart if the allowed_value is a tuple,
            # but not a homogenous one...
            if isinstance(self.allowed_values, types.StringTypes):
                vals = list(self._split_values(value))
            else:
                if isinstance(value, types.TupleType):
                    vals = list(value)
                else:
                    vals = value.split()
            if len(self.default_value) > 0:
                to_type = type(self.default_value[0])
            else:
                to_type = types.StringType
            for i in range(0, len(vals)):
                vals[i] = self._convert(vals[i], to_type)
            return tuple(vals)
        else:
            return self._convert(value, svt)
        raise TypeError, self.name + " has an invalid type."

    def _convert(self, value, to_type):
        '''Convert an int, float or string to the specified type.'''
        if to_type == type(value):
            # already the correct type
            return value
        if to_type == types.IntType:
            return locale.atoi(value)
        if to_type == types.FloatType:
            return locale.atof(value)
        if to_type in types.StringTypes:
            return str(value)
        raise TypeError, "Invalid type."

    def unconvert(self):
        '''Convert value from the appropriate type to a string.'''
        if type(self.value) in types.StringTypes:
            # nothing to do
            return self.value
        if self.is_boolean():
            # A wee bit extra for Python 2.2
            if self.value == True:
                return "True"
            else:
                return "False"
        if type(self.value) == types.TupleType:
            if len(self.value) == 0:
                return ""
            if len(self.value) == 1:
                v = self.value[0]
                if type(v) == types.FloatType:
                    return locale.str(self.value[0])
                return str(v)
            # We need to separate out the items
            strval = ""
            # We use a character that is invalid as the separator
            # so that it will reparse correctly.  We could try all
            # characters, but we make do with this set of commonly
            # used ones - note that the first one that works will
            # be used.  Perhaps a nicer solution than this would be
            # to specifiy a valid delimiter for all options that
            # can have multiple values.  Note that we have None at
            # the end so that this will crash and die if none of
            # the separators works <wink>.
            if self.delimiter is None:
                if type(self.allowed_values) == types.TupleType:
                    self.delimiter = ' '
                else:
                    v0 = self.value[0]
                    v1 = self.value[1]
                    for sep in [' ', ',', ':', ';', '/', '\\', None]:
                        # we know at this point that len(self.value) is at
                        # least two, because len==0 and len==1 were dealt
                        # with as special cases
                        test_str = str(v0) + sep + str(v1)
                        test_tuple = self._split_values(test_str)
                        if test_tuple[0] == str(v0) and \
                           test_tuple[1] == str(v1) and \
                           len(test_tuple) == 2:
                            break
                    # cache this so we don't always need to do the above
                    self.delimiter = sep
            for v in self.value:
                if type(v) == types.FloatType:
                    v = locale.str(v)
                else:
                    v = str(v)
                strval += v + self.delimiter
            strval = strval[:-len(self.delimiter)] # trailing seperator
        else:
            # Otherwise, we just hope str() will do the job
            strval = str(self.value)
        return strval

    def is_boolean(self):
        '''Return True iff the option is a boolean value.'''
        # This is necessary because of the Python 2.2 True=1, False=0
        # cheat.  The valid values are returned as 0 and 1, even if
        # they are actually False and True - but 0 and 1 are not
        # considered valid input (and 0 and 1 don't look as nice)
        # So, just for the 2.2 people, we have this helper function
        try:
            if type(self.allowed_values) == types.TupleType and \
               len(self.allowed_values) > 0 and \
               type(self.allowed_values[0]) == types.BooleanType:
                return True
            return False
        except AttributeError:
            # If the user has Python 2.2 and an option has valid values
            # of (0, 1) - i.e. integers, then this function will return
            # the wrong value.  I don't know what to do about that without
            # explicitly stating which options are boolean
            if self.allowed_values == (False, True):
                return True
            return False


class OptionsClass(object):
    def __init__(self):
        self.verbose = None
        self._options = {}
        self.restore_point = {}
        self.conversion_table = {} # set by creator if they need it.
    #
    # Regular expressions for parsing section headers and options.
    # Lifted straight from ConfigParser
    #
    SECTCRE = re.compile(
        r'\['                                 # [
        r'(?P<header>[^]]+)'                  # very permissive!
        r'\]'                                 # ]
        )
    OPTCRE = re.compile(
        r'(?P<option>[^:=\s][^:=]*)'          # very permissive!
        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
        )

    def update_file(self, filename):
        '''Update the specified configuration file.'''
        sectname = None
        optname = None
        out = TemporaryFile()
        if os.path.exists(filename):
            f = file(filename, "r")
        else:
            # doesn't exist, so create it - all the changed options will
            # be added to it
            if self.verbose:
                print >> sys.stderr, "Creating new configuration file",
                print >> sys.stderr, filename
            f = file(filename, "w")
            f.close()
            f = file(filename, "r")
        written = []
        vi = ": " # default; uses the one from the file where possible
        while True:
            line = f.readline()
            if not line:
                break
            # comment or blank line?
            if line.strip() == '' or line[0] in '#;':
                out.write(line)
                continue
            if line.split(None, 1)[0].lower() == 'rem' and line[0] in "rR":
                # no leading whitespace
                out.write(line)
                continue
            # continuation line?
            if line[0].isspace() and sectname is not None and optname:
                continue
            # a section header or option header?
            else:
                # is it a section header?
                mo = self.SECTCRE.match(line)
                if mo:
                    # Add any missing from the previous section
                    if sectname is not None:
                        self._add_missing(out, written, sectname, vi, False)
                    sectname = mo.group('header')
                    # So sections can't start with a continuation line
                    optname = None
                    if sectname in self.sections():
                        out.write(line)
                # an option line?
                else:
                    mo = self.OPTCRE.match(line)
                    if mo:
                        optname, vi, optval = mo.group('option', 'vi', 'value')
                        if vi in ('=', ':') and ';' in optval:
                            # ';' is a comment delimiter only if it follows
                            # a spacing character
                            pos = optval.find(';')
                            if pos != -1 and optval[pos-1].isspace():
                                optval = optval[:pos]
                        optval = optval.strip()
                        # allow empty values
                        if optval == '""':
                            optval = ''
                        optname = optname.rstrip().lower()
                        if self._options.has_key((sectname, optname)):
                            out.write(optname)
                            out.write(vi)
                            newval = self.unconvert(sectname, optname)
                            out.write(newval.replace("\n", "\n\t"))
                            out.write('\n')
                            written.append((sectname, optname))
        for sect in self.sections():
            self._add_missing(out, written, sect, vi)
        f.close()
        out.flush()
        if self.verbose:
            # save a backup of the old file
            shutil.copyfile(filename, filename + ".bak")
        # copy the new file across
        f = file(filename, "w")
        out.seek(0)
        shutil.copyfileobj(out, f)
        out.close()
        f.close()

    def _add_missing(self, out, written, sect, vi, label=True):
        # add any missing ones, where the value does not equal the default
        for opt in self.options_in_section(sect):
            if not (sect, opt) in written and \
               self.get(sect, opt) != self.default(sect, opt):
                if label:
                    out.write('[')
                    out.write(sect)
                    out.write("]\n")
                    label = False
                out.write(opt)
                out.write(vi)
                newval = self.unconvert(sect, opt)
                out.write(newval.replace("\n", "\n\t"))
                out.write('\n')
                written.append((sect, opt))

    def load_defaults(self, defaults):
        '''Load default values (stored in Options.py).'''
        for section, opts in defaults.items():
            for opt in opts:
                # If first item of the tuple is a sub-class of Option, then
                # instantiate that (with the rest as args).  Otherwise,
                # assume standard Options class.
                klass = Option
                args = opt
                try:
                    if issubclass(opt[0], Option):
                        klass = opt[0]
                        args = opt[1:]
                except TypeError: # opt[0] not a class
                    pass

                o = klass(*args)
                self._options[section, o.name] = o

    def set_restore_point(self):
        '''Remember what the option values are right now, to
        be able to go back to them, via revert_to_restore_point().

        Any existing restore point is wiped.  Restore points do
        not persist over sessions.
        '''
        self.restore_point = {}
        for key, opt_obj in self._options.iteritems():
            self.restore_point[key] = opt_obj.get()

    def revert_to_restore_point(self):
        '''Restore option values to their values when set_restore_point()
        was last called.

        If set_restore_point() has not been called, then this has no
        effect.  If new options have been added since set_restore_point,
        their values are not effected.
        '''
        for key, value in self.restore_point.iteritems():
            self._options[key].set(value)

    def merge_files(self, file_list):
        for f in file_list:
            self.merge_file(f)

    def convert_and_set(self, section, option, value):
        value = self.convert(section, option, value)
        self.set(section, option, value)