"""Base class for all hypervisors
+The syntax for the _CHECK variables and the contents of the PARAMETERS
+dict is the same, see the docstring for L{BaseHypervisor.PARAMETERS}.
+
+@var _FILE_CHECK: stub for file checks, without the required flag
+@var _DIR_CHECK: stub for directory checks, without the required flag
+@var REQ_FILE_CHECK: mandatory file parameter
+@var OPT_FILE_CHECK: optional file parameter
+@var REQ_DIR_CHECK: mandatory directory parametr
+@var OPT_DIR_CHECK: optional directory parameter
+@var NO_CHECK: parameter without any checks at all
+@var REQUIRED_CHECK: parameter required to exist (and non-false), but
+ without other checks; beware that this can't be used for boolean
+ parameters, where you should use NO_CHECK or a custom checker
+
"""
+import os
+import re
+
+
from ganeti import errors
+from ganeti import utils
+
+
+# Read the BaseHypervisor.PARAMETERS docstring for the syntax of the
+# _CHECK values
+
+# must be afile
+_FILE_CHECK = (os.path.isabs, "must be an absolute path",
+ os.path.isfile, "not found or not a file")
+
+# must be a directory
+_DIR_CHECK = (os.path.isabs, "must be an absolute path",
+ os.path.isdir, "not found or not a directory")
+
+# nice wrappers for users
+REQ_FILE_CHECK = (True, ) + _FILE_CHECK
+OPT_FILE_CHECK = (False, ) + _FILE_CHECK
+REQ_DIR_CHECK = (True, ) + _DIR_CHECK
+OPT_DIR_CHECK = (False, ) + _DIR_CHECK
+
+# no checks at all
+NO_CHECK = (False, None, None, None, None)
+
+# required, but no other checks
+REQUIRED_CHECK = (True, None, None, None, None)
+
+def ParamInSet(required, my_set):
+ """Builds parameter checker for set membership.
+
+ @type required: boolean
+ @param required: whether this is a required parameter
+ @type my_set: tuple, list or set
+ @param my_set: allowed values set
+
+ """
+ fn = lambda x: x in my_set
+ err = ("The value must be one of: %s" % utils.CommaJoin(my_set))
+ return (required, fn, err, None, None)
class BaseHypervisor(object):
The goal is that all aspects of the virtualisation technology are
abstracted away from the rest of code.
+ @cvar PARAMETERS: a dict of parameter name: check type; the check type is
+ a five-tuple containing:
+ - the required flag (boolean)
+ - a function to check for syntax, that will be used in
+ L{CheckParameterSyntax}, in the master daemon process
+ - an error message for the above function
+ - a function to check for parameter validity on the remote node,
+ in the L{ValidateParameters} function
+ - an error message for the above function
+
"""
- PARAMETERS = []
+ PARAMETERS = {}
+ ANCILLARY_FILES = []
def __init__(self):
pass
- def StartInstance(self, instance, block_devices, extra_args):
+ def StartInstance(self, instance, block_devices):
"""Start an instance."""
raise NotImplementedError
def GetInstanceInfo(self, instance_name):
"""Get instance properties.
+ @type instance_name: string
@param instance_name: the instance name
@return: tuple (name, id, memory, vcpus, state, times)
"""
raise NotImplementedError
- @staticmethod
- def GetShellCommandForConsole(instance):
+ @classmethod
+ def GetShellCommandForConsole(cls, instance, hvparams, beparams):
"""Return a command for connecting to the console of an instance.
"""
raise NotImplementedError
+ @classmethod
+ def GetAncillaryFiles(cls):
+ """Return a list of ancillary files to be copied to all nodes as ancillary
+ configuration files.
+
+ @rtype: list of strings
+ @return: list of absolute paths of files to ship cluster-wide
+
+ """
+ # By default we return a member variable, so that if an hypervisor has just
+ # a static list of files it doesn't have to override this function.
+ return cls.ANCILLARY_FILES
+
def Verify(self):
"""Verify the hypervisor.
"""
raise NotImplementedError
+ def MigrationInfo(self, instance):
+ """Get instance information to perform a migration.
+
+ By default assume no information is needed.
+
+ @type instance: L{objects.Instance}
+ @param instance: instance to be migrated
+ @rtype: string/data (opaque)
+ @return: instance migration information - serialized form
+
+ """
+ return ''
+
+ def AcceptInstance(self, instance, info, target):
+ """Prepare to accept an instance.
+
+ By default assume no preparation is needed.
+
+ @type instance: L{objects.Instance}
+ @param instance: instance to be accepted
+ @type info: string/data (opaque)
+ @param info: migration information, from the source node
+ @type target: string
+ @param target: target host (usually ip), on this node
+
+ """
+ pass
+
+ def FinalizeMigration(self, instance, info, success):
+ """Finalized an instance migration.
+
+ Should finalize or revert any preparation done to accept the instance.
+ Since by default we do no preparation, we also don't have anything to do
+
+ @type instance: L{objects.Instance}
+ @param instance: instance whose migration is being aborted
+ @type info: string/data (opaque)
+ @param info: migration information, from the source node
+ @type success: boolean
+ @param success: whether the migration was a success or a failure
+
+ """
+ pass
+
def MigrateInstance(self, name, target, live):
"""Migrate an instance.
- Arguments:
- - name: the name of the instance
- - target: the target of the migration (usually will be IP and not name)
- - live: whether to do live migration or not
-
- Returns: none, errors will be signaled by exception.
+ @type name: string
+ @param name: name of the instance to be migrated
+ @type target: string
+ @param target: hostname (usually ip) of the target node
+ @type live: boolean
+ @param live: whether to do a live or non-live migration
"""
raise NotImplementedError
-
@classmethod
def CheckParameterSyntax(cls, hvparams):
"""Check the given parameters for validity.
"""
for key in hvparams:
if key not in cls.PARAMETERS:
- raise errors.HypervisorError("Hypervisor parameter '%s'"
- " not supported" % key)
- for key in cls.PARAMETERS:
- if key not in hvparams:
- raise errors.HypervisorError("Hypervisor parameter '%s'"
- " missing" % key)
-
- def ValidateParameters(self, hvparams):
+ raise errors.HypervisorError("Parameter '%s' is not supported" % key)
+
+ # cheap tests that run on the master, should not access the world
+ for name, (required, check_fn, errstr, _, _) in cls.PARAMETERS.items():
+ if name not in hvparams:
+ raise errors.HypervisorError("Parameter '%s' is missing" % name)
+ value = hvparams[name]
+ if not required and not value:
+ continue
+ if not value:
+ raise errors.HypervisorError("Parameter '%s' is required but"
+ " is currently not defined" % (name, ))
+ if check_fn is not None and not check_fn(value):
+ raise errors.HypervisorError("Parameter '%s' fails syntax"
+ " check: %s (current value: '%s')" %
+ (name, errstr, value))
+
+ @classmethod
+ def ValidateParameters(cls, hvparams):
"""Check the given parameters for validity.
This should check the passed set of parameters for
@raise errors.HypervisorError: when a parameter is not valid
"""
- pass
+ for name, (required, _, _, check_fn, errstr) in cls.PARAMETERS.items():
+ value = hvparams[name]
+ if not required and not value:
+ continue
+ if check_fn is not None and not check_fn(value):
+ raise errors.HypervisorError("Parameter '%s' fails"
+ " validation: %s (current value: '%s')" %
+ (name, errstr, value))
+
+ def GetLinuxNodeInfo(self):
+ """For linux systems, return actual OS information.
+
+ This is an abstraction for all non-hypervisor-based classes, where
+ the node actually sees all the memory and CPUs via the /proc
+ interface and standard commands. The other case if for example
+ xen, where you only see the hardware resources via xen-specific
+ tools.
+
+ @return: a dict with the following keys (values in MiB):
+ - memory_total: the total memory size on the node
+ - memory_free: the available memory on the node for instances
+ - memory_dom0: the memory used by the node itself, if available
+
+ """
+ try:
+ fh = file("/proc/meminfo")
+ try:
+ data = fh.readlines()
+ finally:
+ fh.close()
+ except EnvironmentError, err:
+ raise errors.HypervisorError("Failed to list node info: %s" % (err,))
+
+ result = {}
+ sum_free = 0
+ try:
+ for line in data:
+ splitfields = line.split(":", 1)
+
+ if len(splitfields) > 1:
+ key = splitfields[0].strip()
+ val = splitfields[1].strip()
+ if key == 'MemTotal':
+ result['memory_total'] = int(val.split()[0])/1024
+ elif key in ('MemFree', 'Buffers', 'Cached'):
+ sum_free += int(val.split()[0])/1024
+ elif key == 'Active':
+ result['memory_dom0'] = int(val.split()[0])/1024
+ except (ValueError, TypeError), err:
+ raise errors.HypervisorError("Failed to compute memory usage: %s" %
+ (err,))
+ result['memory_free'] = sum_free
+
+ cpu_total = 0
+ try:
+ fh = open("/proc/cpuinfo")
+ try:
+ cpu_total = len(re.findall("(?m)^processor\s*:\s*[0-9]+\s*$",
+ fh.read()))
+ finally:
+ fh.close()
+ except EnvironmentError, err:
+ raise errors.HypervisorError("Failed to list node info: %s" % (err,))
+ result['cpu_total'] = cpu_total
+ # FIXME: export correct data here
+ result['cpu_nodes'] = 1
+ result['cpu_sockets'] = 1
+
+ return result