summaryrefslogtreecommitdiffstats
path: root/src/lib/Bcfg2/Server/Plugins/GroupPatterns.py
blob: 7fa95fd05b03901164ccb6b8b3fb966c1788f0eb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
""" set group membership based on client hostnames """

import os
import re
import sys
import Bcfg2.Server.Lint
import Bcfg2.Server.Plugin
from Bcfg2.Utils import PackedDigitRange


class PatternMap(object):
    """ Handler for a single pattern or range """

    def __init__(self, pattern, rangestr, groups):
        self.pattern = pattern
        self.rangestr = rangestr
        self.groups = groups
        if pattern is not None:
            self.re = re.compile(pattern)
            self.process = self.process_re
        elif rangestr is not None:
            if '\\' in rangestr:
                raise Exception("Backslashes are not allowed in NameRanges")
            range_finder = r'\[\[[\d\-,]+\]\]'
            self.process = self.process_range
            self.re = re.compile(r'^' + re.sub(range_finder, r'(\d+)',
                                               rangestr))
            dmatcher = re.compile(re.sub(range_finder,
                                         r'\[\[([\d\-,]+)\]\]',
                                         rangestr))
            self.dranges = [PackedDigitRange(x)
                            for x in dmatcher.match(rangestr).groups()]
        else:
            raise Exception("No pattern or range given")

    def process_range(self, name):
        """ match the given hostname against a range-based NameRange """
        match = self.re.match(name)
        if not match:
            return None
        digits = match.groups()
        for grp in range(len(digits)):
            if not self.dranges[grp].includes(digits[grp]):
                return None
        return self.groups

    def process_re(self, name):
        """ match the given hostname against a regex-based NamePattern """
        match = self.re.search(name)
        if not match:
            return None
        ret = list()
        sub = match.groups()
        for group in self.groups:
            newg = group
            for idx in range(len(sub)):
                newg = newg.replace('$%s' % (idx + 1), sub[idx])
            ret.append(newg)
        return ret

    def __str__(self):
        return "%s: %s %s" % (self.__class__.__name__, self.pattern,
                              self.groups)


class PatternFile(Bcfg2.Server.Plugin.XMLFileBacked):
    """ representation of GroupPatterns config.xml """
    __identifier__ = None
    create = 'GroupPatterns'

    def __init__(self, filename, core=None):
        Bcfg2.Server.Plugin.XMLFileBacked.__init__(self, filename,
                                                   should_monitor=True)
        self.core = core
        self.patterns = []

    def Index(self):
        Bcfg2.Server.Plugin.XMLFileBacked.Index(self)
        if (self.core and
                self.core.metadata_cache_mode in ['cautious', 'aggressive']):
            self.core.metadata_cache.expire()
        self.patterns = []
        for entry in self.xdata.xpath('//GroupPattern'):
            try:
                groups = [g.text for g in entry.findall('Group')]
                for pat_ent in entry.findall('NamePattern'):
                    pat = pat_ent.text
                    self.patterns.append(PatternMap(pat, None, groups))
                for range_ent in entry.findall('NameRange'):
                    rng = range_ent.text
                    self.patterns.append(PatternMap(None, rng, groups))
            except:  # pylint: disable=W0702
                self.logger.error("GroupPatterns: Failed to initialize "
                                  "pattern %s: %s" % (entry.text,
                                                      sys.exc_info()[1]))

    def process_patterns(self, hostname):
        """ return a list of groups that should be added to the given
        client based on patterns that match the hostname """
        ret = []
        for pattern in self.patterns:
            try:
                grps = pattern.process(hostname)
                if grps is not None:
                    ret.extend(grps)
            except:  # pylint: disable=W0702
                self.logger.error("GroupPatterns: Failed to process pattern "
                                  "%s for %s" % (pattern.pattern, hostname),
                                  exc_info=1)
        return ret


class GroupPatterns(Bcfg2.Server.Plugin.Plugin,
                    Bcfg2.Server.Plugin.Connector):
    """ set group membership based on client hostnames """

    def __init__(self, core):
        Bcfg2.Server.Plugin.Plugin.__init__(self, core)
        Bcfg2.Server.Plugin.Connector.__init__(self)
        self.config = PatternFile(os.path.join(self.data, 'config.xml'),
                                  core=core)

    def get_additional_groups(self, metadata):
        return self.config.process_patterns(metadata.hostname)