4 # Copyright (C) 2006, 2007 Google Inc.
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.
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.
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
22 """Global Configuration data for Ganeti.
24 This module provides the interface to a special case of cluster
25 configuration data, which is mostly static and available to all nodes.
31 from ganeti import errors
32 from ganeti import constants
33 from ganeti import utils
37 """Interface to static cluster data.
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
47 Other particularities of the datastore:
48 - keys are restricted to predefined values
49 - values are small (<4k)
50 - some keys are handled specially (read from the system)
53 _SS_FILEPREFIX = "ssconf_"
54 SS_HYPERVISOR = "hypervisor"
55 SS_NODED_PASS = "node_pass"
56 SS_MASTER_NODE = "master_node"
57 SS_MASTER_IP = "master_ip"
58 SS_MASTER_NETDEV = "master_netdev"
59 SS_CLUSTER_NAME = "cluster_name"
60 SS_FILE_STORAGE_DIR = "file_storage_dir"
61 SS_CONFIG_VERSION = "config_version"
62 _VALID_KEYS = (SS_HYPERVISOR, SS_NODED_PASS, SS_MASTER_NODE, SS_MASTER_IP,
63 SS_MASTER_NETDEV, SS_CLUSTER_NAME, SS_FILE_STORAGE_DIR,
67 def __init__(self, cfg_location=None):
68 if cfg_location is None:
69 self._cfg_dir = constants.DATA_DIR
71 self._cfg_dir = cfg_location
73 def KeyToFilename(self, key):
74 """Convert a given key into filename.
77 if key not in self._VALID_KEYS:
78 raise errors.ProgrammerError("Invalid key requested from SSConf: '%s'"
81 filename = self._cfg_dir + '/' + self._SS_FILEPREFIX + key
84 def _ReadFile(self, key):
85 """Generic routine to read keys.
87 This will read the file which holds the value requested. Errors
88 will be changed into ConfigurationErrors.
91 filename = self.KeyToFilename(key)
93 fh = file(filename, 'r')
95 data = fh.readline(self._MAX_SIZE)
96 data = data.rstrip('\n')
99 except EnvironmentError, err:
100 raise errors.ConfigurationError("Can't read from the ssconf file:"
104 def GetNodeDaemonPort(self):
105 """Get the node daemon port for this cluster.
107 Note that this routine does not read a ganeti-specific file, but
108 instead uses socket.getservbyname to allow pre-customization of
109 this parameter outside of ganeti.
113 port = socket.getservbyname("ganeti-noded", "tcp")
115 port = constants.DEFAULT_NODED_PORT
119 def GetHypervisorType(self):
120 """Get the hypervisor type for this cluster.
123 return self._ReadFile(self.SS_HYPERVISOR)
125 def GetNodeDaemonPassword(self):
126 """Get the node password for this cluster.
129 return self._ReadFile(self.SS_NODED_PASS)
131 def GetMasterNode(self):
132 """Get the hostname of the master node for this cluster.
135 return self._ReadFile(self.SS_MASTER_NODE)
137 def GetMasterIP(self):
138 """Get the IP of the master node for this cluster.
141 return self._ReadFile(self.SS_MASTER_IP)
143 def GetMasterNetdev(self):
144 """Get the netdev to which we'll add the master ip.
147 return self._ReadFile(self.SS_MASTER_NETDEV)
149 def GetClusterName(self):
150 """Get the cluster name.
153 return self._ReadFile(self.SS_CLUSTER_NAME)
155 def GetFileStorageDir(self):
156 """Get the file storage dir.
159 return self._ReadFile(self.SS_FILE_STORAGE_DIR)
161 def GetConfigVersion(self):
162 """Get the configuration version.
165 value = self._ReadFile(self.SS_CONFIG_VERSION)
168 except (ValueError, TypeError), err:
169 raise errors.ConfigurationError("Failed to convert config version %s to"
170 " int: '%s'" % (value, str(err)))
172 def GetFileList(self):
173 """Return the list of all config files.
175 This is used for computing node replication data.
178 return [self.KeyToFilename(key) for key in self._VALID_KEYS]
181 class WritableSimpleStore(SimpleStore):
182 """This is a read/write interface to SimpleStore, which is used rarely, when
183 values need to be changed. Since WriteFile handles updates in an atomic way
184 it should be fine to use two WritableSimpleStore at the same time, but in
185 the future we might want to put additional protection for this class.
187 A WritableSimpleStore cannot be used to update system-dependent values.
191 def SetKey(self, key, value):
192 """Set the value of a key.
194 This should be used only when adding a node to a cluster, or in other
195 infrequent operations such as cluster-rename or master-failover.
198 file_name = self.KeyToFilename(key)
199 utils.WriteFile(file_name, data="%s\n" % str(value),
200 uid=0, gid=0, mode=0400)