summaryrefslogtreecommitdiffstats
path: root/geo-replication/syncdaemon/configinterface.py
blob: a94e07f0d4b4e2f3c2471af0eb9f540c06205efd (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
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
#
# Copyright (c) 2011-2014 Red Hat, Inc. <http://www.redhat.com>
# This file is part of GlusterFS.

# This file is licensed to you under your choice of the GNU Lesser
# General Public License, version 3 or any later version (LGPLv3 or
# later), or the GNU General Public License, version 2 (GPLv2), in all
# cases as published by the Free Software Foundation.
#

try:
    import ConfigParser
except ImportError:
    # py 3
    import configparser as ConfigParser
import re
from string import Template
import os
import errno
import sys
from stat import ST_DEV, ST_INO, ST_MTIME
import tempfile
import shutil

from syncdutils import escape, unescape, norm, update_file, GsyncdError

SECT_ORD = '__section_order__'
SECT_META = '__meta__'
config_version = 2.0

re_type = type(re.compile(''))


# (SECTION, OPTION, OLD VALUE, NEW VALUE)
CONFIGS = (
    ("peersrx . .",
     "georep_session_working_dir",
     "",
     "/var/lib/glusterd/geo-replication/${mastervol}_${remotehost}_"
     "${slavevol}/"),
    ("peersrx .",
     "gluster_params",
     "aux-gfid-mount xlator-option=\*-dht.assert-no-child-down=true",
     "aux-gfid-mount"),
    ("peersrx . .",
     "ssh_command_tar",
     "",
     "ssh -oPasswordAuthentication=no -oStrictHostKeyChecking=no "
     "-i /var/lib/glusterd/geo-replication/tar_ssh.pem"),
    ("peersrx . .",
     "changelog_log_file",
     "",
     "${iprefix}/log/glusterfs/geo-replication/${mastervol}"
     "/${eSlave}${local_id}-changes.log"),
    ("peersrx . .",
     "working_dir",
     "/var/run/gluster/${mastervol}/${eSlave}",
     "${iprefix}/lib/misc/glusterfsd/${mastervol}/${eSlave}"),
    ("peersrx . .",
     "working_dir",
     "/usr/local/var/run/gluster/${mastervol}/${eSlave}",
     "${iprefix}/lib/misc/glusterfsd/${mastervol}/${eSlave}"),
)


def upgrade_config_file(path):
    config_change = False
    config = ConfigParser.RawConfigParser()
    config.read(path)

    for sec, opt, oldval, newval in CONFIGS:
        try:
            val = config.get(sec, opt)
        except ConfigParser.NoOptionError:
            # if new config opt not exists
            config_change = True
            config.set(sec, opt, newval)
            continue
        except ConfigParser.Error:
            """
            When gsyncd invoked at the time of create, config file
            will not be their. Ignore any ConfigParser errors
            """
            continue

        if val == newval:
            # value is same as new val
            continue

        if val == oldval:
            # config value needs update
            config_change = True
            config.set(sec, opt, newval)

    if config_change:
        tempConfigFile = tempfile.NamedTemporaryFile(mode="wb", delete=False)
        with open(tempConfigFile.name, 'wb') as configFile:
            config.write(configFile)

        # If src and dst are two different file system, then os.rename
        # fails, In this case if temp file created in /tmp and if /tmp is
        # seperate fs then os.rename gives following error, so use shutil
        # OSError: [Errno 18] Invalid cross-device link
        # mail.python.org/pipermail/python-list/2005-February/342893.html
        shutil.move(tempConfigFile.name, path)


class MultiDict(object):

    """a virtual dict-like class which functions as the union
    of underlying dicts"""

    def __init__(self, *dd):
        self.dicts = dd

    def __getitem__(self, key):
        val = None
        for d in self.dicts:
            if d.get(key) is not None:
                val = d[key]
        if val is None:
            raise KeyError(key)
        return val


class GConffile(object):

    """A high-level interface to ConfigParser which flattens the two-tiered
       config layout by implenting automatic section dispatch based on initial
       parameters.

    Also ensure section ordering in terms of their time of addition -- a compat
    hack for Python < 2.7.
    """

    def _normconfig(self):
        """normalize config keys by s/-/_/g"""
        for n, s in self.config._sections.items():
            if n.find('__') == 0:
                continue
            s2 = type(s)()
            for k, v in s.items():
                if k.find('__') != 0:
                    k = norm(k)
                s2[k] = v
            self.config._sections[n] = s2

    def __init__(self, path, peers, *dd):
        """
        - .path: location of config file
        - .config: underlying ConfigParser instance
        - .peers: on behalf of whom we flatten .config
          (master, or master-slave url pair)
        - .auxdicts: template subtituents
        """
        self.peers = peers
        self.path = path
        self.auxdicts = dd
        self.config = ConfigParser.RawConfigParser()
        self.config.read(path)
        self.dev, self.ino, self.mtime = -1, -1, -1
        self._normconfig()

    def _load(self):
        try:
            sres = os.stat(self.path)
            self.dev = sres[ST_DEV]
            self.ino = sres[ST_INO]
            self.mtime = sres[ST_MTIME]
        except (OSError, IOError):
            if sys.exc_info()[1].errno == errno.ENOENT:
                sres = None

        self.config = ConfigParser.RawConfigParser()
        self.config.read(self.path)
        self._normconfig()

    def get_realtime(self, opt):
        try:
            sres = os.stat(self.path)
        except (OSError, IOError):
            if sys.exc_info()[1].errno == errno.ENOENT:
                sres = None
            else:
                raise

        # compare file system stat with that of our stream file handle
        if not sres or sres[ST_DEV] != self.dev or \
           sres[ST_INO] != self.ino or self.mtime != sres[ST_MTIME]:
            self._load()

        return self.get(opt, printValue=False)

    def section(self, rx=False):
        """get the section name of the section representing .peers
        in .config"""
        peers = self.peers
        if not peers:
            peers = ['.', '.']
            rx = True
        if rx:
            st = 'peersrx'
        else:
            st = 'peers'
        return ' '.join([st] + [escape(u) for u in peers])

    @staticmethod
    def parse_section(section):
        """retrieve peers sequence encoded by section name
           (as urls or regexen, depending on section type)
        """
        sl = section.split()
        st = sl.pop(0)
        sl = [unescape(u) for u in sl]
        if st == 'peersrx':
            sl = [re.compile(u) for u in sl]
        return sl

    def ord_sections(self):
        """Return an ordered list of sections.

        Ordering happens based on the auxiliary
        SECT_ORD section storing indices for each
        section added through the config API.

        To not to go corrupt in case of manually
        written config files, we take care to append
        also those sections which are not registered
        in SECT_ORD.

        Needed for python 2.{4,5,6} where ConfigParser
        cannot yet order sections/options internally.
        """
        so = {}
        if self.config.has_section(SECT_ORD):
            so = self.config._sections[SECT_ORD]
        so2 = {}
        for k, v in so.items():
            if k != '__name__':
                so2[k] = int(v)
        tv = 0
        if so2:
            tv = max(so2.values()) + 1
        ss = [s for s in self.config.sections() if s.find('__') != 0]
        for s in ss:
            if s in so.keys():
                continue
            so2[s] = tv
            tv += 1

        def scmp(x, y):
            return cmp(*(so2[s] for s in (x, y)))
        ss.sort(scmp)
        return ss

    def update_to(self, dct, allow_unresolved=False):
        """update @dct from key/values of ours.

        key/values are collected from .config by filtering the regexp sections
        according to match, and from .section. The values are treated as
        templates, which are substituted from .auxdicts and (in case of regexp
        sections) match groups.
        """
        if not self.peers:
            raise GsyncdError('no peers given, cannot select matching options')

        def update_from_sect(sect, mud):
            for k, v in self.config._sections[sect].items():
                if k == '__name__':
                    continue
                if allow_unresolved:
                    dct[k] = Template(v).safe_substitute(mud)
                else:
                    dct[k] = Template(v).substitute(mud)
        for sect in self.ord_sections():
            sp = self.parse_section(sect)
            if isinstance(sp[0], re_type) and len(sp) == len(self.peers):
                match = True
                mad = {}
                for i in range(len(sp)):
                    m = sp[i].search(self.peers[i])
                    if not m:
                        match = False
                        break
                    for j in range(len(m.groups())):
                        mad['match%d_%d' % (i + 1, j + 1)] = m.groups()[j]
                if match:
                    update_from_sect(sect, MultiDict(dct, mad, *self.auxdicts))
        if self.config.has_section(self.section()):
            update_from_sect(self.section(), MultiDict(dct, *self.auxdicts))

    def get(self, opt=None, printValue=True):
        """print the matching key/value pairs from .config,
           or if @opt given, the value for @opt (according to the
           logic described in .update_to)
        """
        d = {}
        self.update_to(d, allow_unresolved=True)
        if opt:
            opt = norm(opt)
            v = d.get(opt)
            if v:
                if printValue:
                    print(v)
                else:
                    return v
        else:
            for k, v in d.iteritems():
                if k == '__name__':
                    continue
                print("%s: %s" % (k, v))

    def write(self, trfn, opt, *a, **kw):
        """update on-disk config transactionally

        @trfn is the transaction function
        """
        def mergeconf(f):
            self.config = ConfigParser.RawConfigParser()
            self.config.readfp(f)
            self._normconfig()
            if not self.config.has_section(SECT_META):
                self.config.add_section(SECT_META)
            self.config.set(SECT_META, 'version', config_version)
            return trfn(norm(opt), *a, **kw)

        def updateconf(f):
            self.config.write(f)
        update_file(self.path, updateconf, mergeconf)

    def _set(self, opt, val, rx=False):
        """set @opt to @val in .section"""
        sect = self.section(rx)
        if not self.config.has_section(sect):
            self.config.add_section(sect)
            # regarding SECT_ORD, cf. ord_sections
            if not self.config.has_section(SECT_ORD):
                self.config.add_section(SECT_ORD)
            self.config.set(
                SECT_ORD, sect, len(self.config._sections[SECT_ORD]))
        self.config.set(sect, opt, val)
        return True

    def set(self, opt, *a, **kw):
        """perform ._set transactionally"""
        self.write(self._set, opt, *a, **kw)

    def _delete(self, opt, rx=False):
        """delete @opt from .section"""
        sect = self.section(rx)
        if self.config.has_section(sect):
            return self.config.remove_option(sect, opt)

    def delete(self, opt, *a, **kw):
        """perform ._delete transactionally"""
        self.write(self._delete, opt, *a, **kw)