root / lib / ssconf.py @ 41a57aab
History | View | Annotate | Download (5 kB)
1 |
#
|
---|---|
2 |
#
|
3 |
|
4 |
# Copyright (C) 2006, 2007 Google Inc.
|
5 |
#
|
6 |
# This program is free software; you can redistribute it and/or modify
|
7 |
# it under the terms of the GNU General Public License as published by
|
8 |
# the Free Software Foundation; either version 2 of the License, or
|
9 |
# (at your option) any later version.
|
10 |
#
|
11 |
# This program is distributed in the hope that it will be useful, but
|
12 |
# WITHOUT ANY WARRANTY; without even the implied warranty of
|
13 |
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
14 |
# General Public License for more details.
|
15 |
#
|
16 |
# You should have received a copy of the GNU General Public License
|
17 |
# along with this program; if not, write to the Free Software
|
18 |
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
|
19 |
# 02110-1301, USA.
|
20 |
|
21 |
|
22 |
"""Global Configuration data for Ganeti.
|
23 |
|
24 |
This module provides the interface to a special case of cluster
|
25 |
configuration data, which is mostly static and available to all nodes.
|
26 |
|
27 |
"""
|
28 |
|
29 |
import socket |
30 |
|
31 |
from ganeti import errors |
32 |
from ganeti import constants |
33 |
from ganeti import utils |
34 |
|
35 |
|
36 |
class SimpleStore: |
37 |
"""Interface to static cluster data.
|
38 |
|
39 |
This is different that the config.ConfigWriter class in that it
|
40 |
holds data that is (mostly) constant after the cluster
|
41 |
initialization. Its purpose is to allow limited customization of
|
42 |
things which would otherwise normally live in constants.py. Note
|
43 |
that this data cannot live in ConfigWriter as that is available only
|
44 |
on the master node, and our data must be readable by both the master
|
45 |
and the nodes.
|
46 |
|
47 |
Other particularities of the datastore:
|
48 |
- keys are restricted to predefined values
|
49 |
- values are small (<4k)
|
50 |
- since the data is practically static, read keys are cached in memory
|
51 |
- some keys are handled specially (read from the system, so
|
52 |
we can't update them)
|
53 |
|
54 |
"""
|
55 |
_SS_FILEPREFIX = "ssconf_"
|
56 |
SS_HYPERVISOR = "hypervisor"
|
57 |
SS_NODED_PASS = "node_pass"
|
58 |
SS_MASTER_NODE = "master_node"
|
59 |
SS_MASTER_IP = "master_ip"
|
60 |
SS_MASTER_NETDEV = "master_netdev"
|
61 |
SS_CLUSTER_NAME = "cluster_name"
|
62 |
_VALID_KEYS = (SS_HYPERVISOR, SS_NODED_PASS, SS_MASTER_NODE, SS_MASTER_IP, |
63 |
SS_MASTER_NETDEV, SS_CLUSTER_NAME) |
64 |
_MAX_SIZE = 4096
|
65 |
|
66 |
def __init__(self, cfg_location=None): |
67 |
if cfg_location is None: |
68 |
self._cfg_dir = constants.DATA_DIR
|
69 |
else:
|
70 |
self._cfg_dir = cfg_location
|
71 |
self._cache = {}
|
72 |
|
73 |
def KeyToFilename(self, key): |
74 |
"""Convert a given key into filename.
|
75 |
|
76 |
"""
|
77 |
if key not in self._VALID_KEYS: |
78 |
raise errors.ProgrammerError("Invalid key requested from SSConf: '%s'" |
79 |
% str(key))
|
80 |
|
81 |
filename = self._cfg_dir + '/' + self._SS_FILEPREFIX + key |
82 |
return filename
|
83 |
|
84 |
def _ReadFile(self, key): |
85 |
"""Generic routine to read keys.
|
86 |
|
87 |
This will read the file which holds the value requested. Errors
|
88 |
will be changed into ConfigurationErrors.
|
89 |
|
90 |
"""
|
91 |
if key in self._cache: |
92 |
return self._cache[key] |
93 |
filename = self.KeyToFilename(key)
|
94 |
try:
|
95 |
fh = file(filename, 'r') |
96 |
try:
|
97 |
data = fh.readline(self._MAX_SIZE)
|
98 |
data = data.rstrip('\n')
|
99 |
finally:
|
100 |
fh.close() |
101 |
except EnvironmentError, err: |
102 |
raise errors.ConfigurationError("Can't read from the ssconf file:" |
103 |
" '%s'" % str(err)) |
104 |
self._cache[key] = data
|
105 |
return data
|
106 |
|
107 |
def GetNodeDaemonPort(self): |
108 |
"""Get the node daemon port for this cluster.
|
109 |
|
110 |
Note that this routine does not read a ganeti-specific file, but
|
111 |
instead uses socket.getservbyname to allow pre-customization of
|
112 |
this parameter outside of ganeti.
|
113 |
|
114 |
"""
|
115 |
try:
|
116 |
port = socket.getservbyname("ganeti-noded", "tcp") |
117 |
except socket.error:
|
118 |
port = constants.DEFAULT_NODED_PORT |
119 |
|
120 |
return port
|
121 |
|
122 |
def GetHypervisorType(self): |
123 |
"""Get the hypervisor type for this cluster.
|
124 |
|
125 |
"""
|
126 |
return self._ReadFile(self.SS_HYPERVISOR) |
127 |
|
128 |
def GetNodeDaemonPassword(self): |
129 |
"""Get the node password for this cluster.
|
130 |
|
131 |
"""
|
132 |
return self._ReadFile(self.SS_NODED_PASS) |
133 |
|
134 |
def GetMasterNode(self): |
135 |
"""Get the hostname of the master node for this cluster.
|
136 |
|
137 |
"""
|
138 |
return self._ReadFile(self.SS_MASTER_NODE) |
139 |
|
140 |
def GetMasterIP(self): |
141 |
"""Get the IP of the master node for this cluster.
|
142 |
|
143 |
"""
|
144 |
return self._ReadFile(self.SS_MASTER_IP) |
145 |
|
146 |
def GetMasterNetdev(self): |
147 |
"""Get the netdev to which we'll add the master ip.
|
148 |
|
149 |
"""
|
150 |
return self._ReadFile(self.SS_MASTER_NETDEV) |
151 |
|
152 |
def GetClusterName(self): |
153 |
"""Get the cluster name.
|
154 |
|
155 |
"""
|
156 |
return self._ReadFile(self.SS_CLUSTER_NAME) |
157 |
|
158 |
def SetKey(self, key, value): |
159 |
"""Set the value of a key.
|
160 |
|
161 |
This should be used only when adding a node to a cluster.
|
162 |
|
163 |
"""
|
164 |
file_name = self.KeyToFilename(key)
|
165 |
utils.WriteFile(file_name, data="%s\n" % str(value), |
166 |
uid=0, gid=0, mode=0400) |
167 |
self._cache[key] = value
|
168 |
|
169 |
def GetFileList(self): |
170 |
"""Return the lis of all config files.
|
171 |
|
172 |
This is used for computing node replication data.
|
173 |
|
174 |
"""
|
175 |
return [self.KeyToFilename(key) for key in self._VALID_KEYS] |