summaryrefslogtreecommitdiff
path: root/src/leap/base/config.py
blob: 6d43a8952c26f8663405fb2c42adea88b1e99978 (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
"""
Configuration Base Class
"""
import grp
import json
import logging
import socket
import time
import os

logger = logging.getLogger(name=__name__)

from dateutil import parser as dateparser
import dirspec
import requests

from leap.base import exceptions
from leap.base import constants
from leap.base.pluggableconfig import PluggableConfig
from leap.util.fileutil import (mkdir_p)

# move to base!
from leap.eip import exceptions as eipexceptions


class BaseLeapConfig(object):
    slug = None

    # XXX we have to enforce that every derived class
    # has a slug (via interface)
    # get property getter that raises NI..

    def save(self):
        raise NotImplementedError("abstract base class")

    def load(self):
        raise NotImplementedError("abstract base class")

    def get_config(self, *kwargs):
        raise NotImplementedError("abstract base class")

    @property
    def config(self):
        return self.get_config()

    def get_value(self, *kwargs):
        raise NotImplementedError("abstract base class")


class MetaConfigWithSpec(type):
    """
    metaclass for JSONLeapConfig classes.
    It creates a configuration spec out of
    the `spec` dictionary. The `properties` attribute
    of the spec dict is turn into the `schema` attribute
    of the new class (which will be used to validate against).
    """
    # XXX in the near future, this is the
    # place where we want to enforce
    # singletons, read-only and similar stuff.

    def __new__(meta, classname, bases, classDict):
        schema_obj = classDict.get('spec', None)

        # not quite happy with this workaround.
        # I want to raise if missing spec dict, but only
        # for grand-children of this metaclass.
        # maybe should use abc module for this.
        abcderived = ("JSONLeapConfig",)
        if schema_obj is None and classname not in abcderived:
            raise exceptions.ImproperlyConfigured(
                "missing spec dict on your derived class (%s)" % classname)

        # we create a configuration spec attribute
        # from the spec dict
        config_class = type(
            classname + "Spec",
            (PluggableConfig, object),
            {'options': schema_obj})
        classDict['spec'] = config_class

        return type.__new__(meta, classname, bases, classDict)

##########################################################
# some hacking still in progress:

# Configs have:

# - a slug (from where a filename/folder is derived)
# - a spec (for validation and defaults).
#   this spec is conformant to the json-schema.
#   basically a dict that will be used
#   for type casting and validation, and defaults settings.

# all config objects, since they are derived from  BaseConfig, implement basic
# useful methods:
# - save
# - load

##########################################################


class JSONLeapConfig(BaseLeapConfig):

    __metaclass__ = MetaConfigWithSpec

    def __init__(self, *args, **kwargs):
        # sanity check
        try:
            assert self.slug is not None
        except AssertionError:
            raise exceptions.ImproperlyConfigured(
                "missing slug on JSONLeapConfig"
                " derived class")
        try:
            assert self.spec is not None
        except AssertionError:
            raise exceptions.ImproperlyConfigured(
                "missing spec on JSONLeapConfig"
                " derived class")
        assert issubclass(self.spec, PluggableConfig)

        self.domain = kwargs.pop('domain', None)
        self._config = self.spec(format="json")
        self._config.load()
        self.fetcher = kwargs.pop('fetcher', requests)

    # mandatory baseconfig interface

    def save(self, to=None, force=False):
        """
        force param will skip the dirty check.
        :type force: bool
        """
        # XXX this force=True does not feel to right
        # but still have to look for a better way
        # of dealing with dirtiness and the
        # trick of loading remote config only
        # when newer.

        if force:
            do_save = True
        else:
            do_save = self._config.is_dirty()

        if do_save:
            if to is None:
                to = self.filename
            folder, filename = os.path.split(to)
            if folder and not os.path.isdir(folder):
                mkdir_p(folder)
            self._config.serialize(to)
            return True

        else:
            return False

    def load(self, fromfile=None, from_uri=None, fetcher=None,
             force_download=False, verify=True):

        if from_uri is not None:
            fetched = self.fetch(
                from_uri,
                fetcher=fetcher,
                verify=verify,
                force_dl=force_download)
            if fetched:
                return
        if fromfile is None:
            fromfile = self.filename
        if os.path.isfile(fromfile):
            self._config.load(fromfile=fromfile)
        else:
            logger.error('tried to load config from non-existent path')
            logger.error('Not Found: %s', fromfile)

    def fetch(self, uri, fetcher=None, verify=True, force_dl=False):
        if not fetcher:
            fetcher = self.fetcher

        logger.debug('uri: %s (verify: %s)' % (uri, verify))

        rargs = (uri, )
        rkwargs = {'verify': verify}
        headers = {}

        curmtime = self.get_mtime() if not force_dl else None
        if curmtime:
            logger.debug('requesting with if-modified-since %s' % curmtime)
            headers['if-modified-since'] = curmtime
            rkwargs['headers'] = headers

        #request = fetcher.get(uri, verify=verify)
        request = fetcher.get(*rargs, **rkwargs)
        request.raise_for_status()

        if request.status_code == 304:
            logger.debug('...304 Not Changed')
            # On this point, we have to assume that
            # we HAD the filename. If that filename is corruct,
            # we should enforce a force_download in the load
            # method above.
            self._config.load(fromfile=self.filename)
            return True

        if request.json:
            mtime = None
            last_modified = request.headers.get('last-modified', None)
            if last_modified:
                _mtime = dateparser.parse(last_modified)
                mtime = int(_mtime.strftime("%s"))
            if callable(request.json):
                _json = request.json()
            else:
                # back-compat
                _json = request.json
            self._config.load(json.dumps(_json), mtime=mtime)
            self._config.set_dirty()
        else:
            # not request.json
            # might be server did not announce content properly,
            # let's try deserializing all the same.
            try:
                self._config.load(request.content)
                self._config.set_dirty()
            except ValueError:
                raise eipexceptions.LeapBadConfigFetchedError

        return True

    def get_mtime(self):
        try:
            _mtime = os.stat(self.filename)[8]
            mtime = time.strftime("%c GMT", time.gmtime(_mtime))
            return mtime
        except OSError:
            return None

    def get_config(self):
        return self._config.config

    # public methods

    def get_filename(self):
        return self._slug_to_filename()

    @property
    def filename(self):
        return self.get_filename()

    def validate(self, data):
        logger.debug('validating schema')
        self._config.validate(data)
        return True

    # private

    def _slug_to_filename(self):
        # is this going to work in winland if slug is "foo/bar" ?
        folder, filename = os.path.split(self.slug)
        config_file = get_config_file(filename, folder)
        return config_file

    def exists(self):
        return os.path.isfile(self.filename)


#
# utility functions
#
# (might be moved to some class as we see fit, but
# let's remain functional for a while)
# maybe base.config.util ??
#


def get_config_dir():
    """
    get the base dir for all leap config
    @rparam: config path
    @rtype: string
    """
    return os.path.join(dirspec.basedir.default_config_home,
                        'leap')


def get_config_file(filename, folder=None):
    """
    concatenates the given filename
    with leap config dir.
    @param filename: name of the file
    @type filename: string
    @rparam: full path to config file
    """
    path = []
    path.append(get_config_dir())
    if folder is not None:
        path.append(folder)
    path.append(filename)
    return os.path.join(*path)


def get_default_provider_path():
    default_subpath = os.path.join("providers",
                                   constants.DEFAULT_PROVIDER)
    default_provider_path = get_config_file(
        '',
        folder=default_subpath)
    return default_provider_path


def get_provider_path(domain):
    # XXX if not domain, return get_default_provider_path
    default_subpath = os.path.join("providers", domain)
    provider_path = get_config_file(
        '',
        folder=default_subpath)
    return provider_path


def validate_ip(ip_str):
    """
    raises exception if the ip_str is
    not a valid representation of an ip
    """
    socket.inet_aton(ip_str)


def get_username():
    try:
        return os.getlogin()
    except OSError as e:
        import pwd
        return pwd.getpwuid(os.getuid())[0]


def get_groupname():
    gid = os.getgroups()[-1]
    return grp.getgrgid(gid).gr_name