summaryrefslogtreecommitdiff
path: root/util.py
blob: 5d1e263ec000c2c871001e56045338943a6ec267 (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
import os
import gnupg
import re

class GPGWrapper(gnupg.GPG):
    """
    This is a temporary class for handling GPG requests, and should be
    replaced by a more general class used throughout the project.
    """

    GNUPG_HOME    = os.environ['HOME'] + "/.config/leap/gnupg"
    GNUPG_BINARY  = "/usr/bin/gpg" # this has to be changed based on OS

    def __init__(self, gpghome=GNUPG_HOME, gpgbinary=GNUPG_BINARY):
        super(GPGWrapper, self).__init__(gnupghome=gpghome, gpgbinary=gpgbinary)

    def find_key(self, email):
        """
        Find user's key based on their email.
        """
        for key in self.list_keys():
            for uid in key['uids']:
                if re.search(email, uid):
                    return key
        raise LookupError("GnuPG public key for %s not found!" % email)

    def encrypt(self, data, recipient, sign=None, always_trust=True,
                passphrase=None, symmetric=False):
        # TODO: devise a way so we don't need to "always trust".
        return super(GPGWrapper, self).encrypt(data, recipient, sign=sign,
                                               always_trust=always_trust,
                                               passphrase=passphrase,
                                               symmetric=symmetric)

    def decrypt(self, data, always_trust=True, passphrase=None):
        # TODO: devise a way so we don't need to "always trust".
        return super(GPGWrapper, self).decrypt(data,
                                               always_trust=always_trust,
                                               passphrase=passphrase)


#----------------------------------------------------------------------------
# u1db Transaction and Sync logs.
#----------------------------------------------------------------------------

class SimpleLog(object):
    def __init__(self):
        self._log = []

    def _set_log(self, log):
        self._log = log

    def _get_log(self):
        return self._log

    log = property(
        _get_log, _set_log, doc="Log contents.")

    def append(self, msg):
        self._log.append(msg)

    def reduce(self, func, initializer=None):
        return reduce(func, self.log, initializer)

    def map(self, func):
        return map(func, self.log)

    def filter(self, func):
        return filter(func, self.log)


class TransactionLog(SimpleLog):
    """
    An ordered list of (generation, doc_id, transaction_id) tuples.
    """

    def _set_log(self, log):
        self._log = log

    def _get_log(self):
        return sorted(self._log, reverse=True)

    log = property(
        _get_log, _set_log, doc="Log contents.")

    def get_generation(self):
        """
        Return the current generation.
        """
        gens = self.map(lambda x: x[0])
        if not gens:
            return 0
        return max(gens)

    def get_generation_info(self):
        """
        Return the current generation and transaction id.
        """
        if not self._log:
            return(0, '')
        info = self.map(lambda x: (x[0], x[2]))
        return reduce(lambda x, y: x if (x[0] > y[0]) else y, info)

    def get_trans_id_for_gen(self, gen):
        """
        Get the transaction id corresponding to a particular generation.
        """
        log = self.reduce(lambda x, y: y if y[0] == gen else x)
        if log is None:
            return None
        return log[2]

    def whats_changed(self, old_generation):
        """
        Return a list of documents that have changed since old_generation.
        """
        results = self.filter(lambda x: x[0] > old_generation)
        seen = set()
        changes = []
        newest_trans_id = ''
        for generation, doc_id, trans_id in results:
            if doc_id not in seen:
                changes.append((doc_id, generation, trans_id))
                seen.add(doc_id)
        if changes:
            cur_gen = changes[0][1]  # max generation
            newest_trans_id = changes[0][2]
            changes.reverse()
        else:
            results = self.log
            if not results:
                cur_gen = 0
                newest_trans_id = ''
            else:
                cur_gen, _, newest_trans_id = results[0]

        return cur_gen, newest_trans_id, changes
        


class SyncLog(SimpleLog):
    """
    A list of (replica_id, generation, transaction_id) tuples.
    """

    def find_by_replica_uid(self, replica_uid):
        if not self.log:
            return ()
        return self.reduce(lambda x, y: y if y[0] == replica_uid else x)

    def get_replica_gen_and_trans_id(self, other_replica_uid):
        """
        Return the last known generation and transaction id for the other db
        replica.
        """
        info = self.find_by_replica_uid(other_replica_uid)
        if not info:
            return (0, '')
        return (info[1], info[2])

    def set_replica_gen_and_trans_id(self, other_replica_uid,
                                      other_generation, other_transaction_id):
        """
        Set the last-known generation and transaction id for the other
        database replica.
        """
        self.log = self.filter(lambda x: x[0] != other_replica_uid)
        self.append((other_replica_uid, other_generation,
                     other_transaction_id))