LUSetInstanceParams: abstract _GetUpdatedParams

[ganeti-local] / lib / ssconf.py

diff --git a/lib/ssconf.py b/lib/ssconf.py
index 9165f12..cce1141 100644 (file)
--- a/lib/ssconf.py
+++ b/lib/ssconf.py
@@ -112,31 +112,143 @@ class SimpleConfigWriter(SimpleConfigReader):
                     mode=0600)
 
 
                     mode=0600)
 
 

-def _SsconfPath(name):
-  if not RE_VALID_SSCONF_NAME.match(name):
-    raise errors.ParameterError("Invalid ssconf name: %s" % name)
-  return "%s/ssconf_%s" % (constants.DATA_DIR, name)
+class SimpleStore(object):
+  """Interface to static cluster data.

 
 

+  This is different that the config.ConfigWriter and
+  SimpleConfigReader classes in that it holds data that will always be
+  present, even on nodes which don't have all the cluster data.

 
 

-def WriteSsconfFiles(values):
-  """Writes legacy ssconf files to be used by external scripts.
-
-  @type values: dict
-  @param values: Dictionary of (name, value)
+  Other particularities of the datastore:
+    - keys are restricted to predefined values

 
   """
 
   """

-  ssconf_lock = utils.FileLock(constants.SSCONF_LOCK_FILE)
+  _SS_FILEPREFIX = "ssconf_"
+  _VALID_KEYS = (
+    constants.SS_CLUSTER_NAME,
+    constants.SS_CLUSTER_TAGS,
+    constants.SS_FILE_STORAGE_DIR,
+    constants.SS_MASTER_CANDIDATES,
+    constants.SS_MASTER_IP,
+    constants.SS_MASTER_NETDEV,
+    constants.SS_MASTER_NODE,
+    constants.SS_NODE_LIST,
+    constants.SS_OFFLINE_NODES,
+    constants.SS_ONLINE_NODES,
+    constants.SS_INSTANCE_LIST,
+    constants.SS_RELEASE_VERSION,
+    )
+  _MAX_SIZE = 131072
+
+  def __init__(self, cfg_location=None):
+    if cfg_location is None:
+      self._cfg_dir = constants.DATA_DIR
+    else:
+      self._cfg_dir = cfg_location
+
+  def KeyToFilename(self, key):
+    """Convert a given key into filename.

 
 

-  # Get lock while writing files
-  ssconf_lock.Exclusive(blocking=True, timeout=SSCONF_LOCK_TIMEOUT)
-  try:
-    for name, value in values.iteritems():
-      if not value.endswith("\n"):
-        value += "\n"
-      utils.WriteFile(_SsconfPath(name),
-                      data=value)
-  finally:
-    ssconf_lock.Unlock()
+    """
+    if key not in self._VALID_KEYS:
+      raise errors.ProgrammerError("Invalid key requested from SSConf: '%s'"
+                                   % str(key))
+
+    filename = self._cfg_dir + '/' + self._SS_FILEPREFIX + key
+    return filename
+
+  def _ReadFile(self, key):
+    """Generic routine to read keys.
+
+    This will read the file which holds the value requested. Errors
+    will be changed into ConfigurationErrors.
+
+    """
+    filename = self.KeyToFilename(key)
+    try:
+      fh = file(filename, 'r')
+      try:
+        data = fh.read(self._MAX_SIZE)
+        data = data.rstrip('\n')
+      finally:
+        fh.close()
+    except EnvironmentError, err:
+      raise errors.ConfigurationError("Can't read from the ssconf file:"
+                                      " '%s'" % str(err))
+    return data
+
+  def WriteFiles(self, values):
+    """Writes ssconf files used by external scripts.
+
+    @type values: dict
+    @param values: Dictionary of (name, value)
+
+    """
+    ssconf_lock = utils.FileLock(constants.SSCONF_LOCK_FILE)
+
+    # Get lock while writing files
+    ssconf_lock.Exclusive(blocking=True, timeout=SSCONF_LOCK_TIMEOUT)
+    try:
+      for name, value in values.iteritems():
+        if value and not value.endswith("\n"):
+          value += "\n"
+        utils.WriteFile(self.KeyToFilename(name), data=value, mode=0444)
+    finally:
+      ssconf_lock.Unlock()
+
+  def GetFileList(self):
+    """Return the list of all config files.
+
+    This is used for computing node replication data.
+
+    """
+    return [self.KeyToFilename(key) for key in self._VALID_KEYS]
+
+  def GetClusterName(self):
+    """Get the cluster name.
+
+    """
+    return self._ReadFile(constants.SS_CLUSTER_NAME)
+
+  def GetFileStorageDir(self):
+    """Get the file storage dir.
+
+    """
+    return self._ReadFile(constants.SS_FILE_STORAGE_DIR)
+
+  def GetMasterCandidates(self):
+    """Return the list of master candidates.
+
+    """
+    data = self._ReadFile(constants.SS_MASTER_CANDIDATES)
+    nl = data.splitlines(False)
+    return nl
+
+  def GetMasterIP(self):
+    """Get the IP of the master node for this cluster.
+
+    """
+    return self._ReadFile(constants.SS_MASTER_IP)
+
+  def GetMasterNetdev(self):
+    """Get the netdev to which we'll add the master ip.
+
+    """
+    return self._ReadFile(constants.SS_MASTER_NETDEV)
+
+  def GetMasterNode(self):
+    """Get the hostname of the master node for this cluster.
+
+    """
+    return self._ReadFile(constants.SS_MASTER_NODE)
+
+  def GetNodeList(self):
+    """Return the list of cluster nodes.
+
+    """
+    data = self._ReadFile(constants.SS_NODE_LIST)
+    nl = data.splitlines(False)
+    return nl

 
 
 def GetMasterAndMyself(ss=None):
 
 
 def GetMasterAndMyself(ss=None):

@@ -148,9 +260,14 @@ def GetMasterAndMyself(ss=None):
   The function does not handle any errors, these should be handled in
   the caller (errors.ConfigurationError, errors.ResolverError).
 
   The function does not handle any errors, these should be handled in
   the caller (errors.ConfigurationError, errors.ResolverError).
 

+  @param ss: either a sstore.SimpleConfigReader or a
+      sstore.SimpleStore instance
+  @rtype: tuple
+  @return: a tuple (master node name, my own name)
+

   """
   if ss is None:
   """
   if ss is None:

-    ss = SimpleConfigReader()
+    ss = SimpleStore()

   return ss.GetMasterNode(), utils.HostInfo().name
 
 
   return ss.GetMasterNode(), utils.HostInfo().name