def test_mix_errors_timeout(self):
"""Test the result of mixed timeout and error actions."""
action = Action(name='start', target='badname,timeout,localhost',
command='/bin/true', timeout=0.9)
action.errors = 1
service = Service('test_service')
service.add_action(action)
service.run('start')
self.assertEqual(action.nodes_error(), NodeSet('badname'))
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nodes_timeout(), NodeSet('timeout'))
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, ERROR)
service.reset()
action.errors = 2
service.run('start')
self.assertEqual(action.nodes_error(), NodeSet('badname'))
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nodes_timeout(), NodeSet('timeout'))
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, WARNING)
service.reset()
action.errors = 2
action.warnings = 2
service.run('start')
self.assertEqual(action.nodes_error(), NodeSet('badname'))
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nodes_timeout(), NodeSet('timeout'))
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, DONE)
def reset(self):
'''Reset values of attributes in order to perform multiple exec'''
Service.reset(self)
for service in self._subservices.values():
service.reset()
self._sink.reset()
self._source.reset()
def test_missing_action(self):
"""Test prepare with service with missing action is ok"""
# Graph leaf has no 'status' action
s1 = Service("1")
s1.add_action(Action('start', command='/bin/true'))
s1.add_action(Action('status', command='/bin/true'))
s2 = Service("2")
s2.add_action(Action('start', command='/bin/true'))
s2.add_dep(s1)
s2.run('status')
self.assertEqual(s1.status, DONE)
self.assertEqual(s2.status, MISSING)
s1.reset()
s2.reset()
self.assertEqual(s1.status, NO_STATUS)
self.assertEqual(s2.status, NO_STATUS)
# 'status' action is propagated to leaf even if '2' has not the
# requested action.
s3 = Service("3")
s3.add_action(Action('start', command='/bin/true'))
s3.add_action(Action('status', command='/bin/true'))
s3.add_dep(s2)
s3.run('status')
self.assertEqual(s1.status, DONE)
self.assertEqual(s2.status, MISSING)
self.assertEqual(s3.status, DONE)
def test_missing_action(self):
"""Test prepare with service with missing action is ok"""
# Graph leaf has no 'status' action
s1 = Service("1")
s1.add_action(Action('start', command='/bin/true'))
s1.add_action(Action('status', command='/bin/true'))
s2 = Service("2")
s2.add_action(Action('start', command='/bin/true'))
s2.add_dep(s1)
s2.run('status')
self.assertEqual(s1.status, DONE)
self.assertEqual(s2.status, MISSING)
s1.reset()
s2.reset()
self.assertEqual(s1.status, NO_STATUS)
self.assertEqual(s2.status, NO_STATUS)
# 'status' action is propagated to leaf even if '2' has not the
# requested action.
s3 = Service("3")
s3.add_action(Action('start', command='/bin/true'))
s3.add_action(Action('status', command='/bin/true'))
s3.add_dep(s2)
s3.run('status')
self.assertEqual(s1.status, DONE)
self.assertEqual(s2.status, MISSING)
self.assertEqual(s3.status, DONE)
def reset(self):
'''Reset values of attributes in order to perform multiple exec'''
Service.reset(self)
for service in self._subservices.values():
service.reset()
self._sink.reset()
self._source.reset()
def test_mix_errors_timeout(self):
"""Test the result of mixed timeout and error actions."""
# timeout host configuration is in setup_sshconfig (__init__.py)
action = Action(name='start',
target='badname,timeout,localhost',
command='/bin/true',
timeout=0.9)
action.errors = 1
service = Service('test_service')
service.add_action(action)
service.run('start')
self.assertEqual(action.nodes_error(), NodeSet('badname'))
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nodes_timeout(), NodeSet('timeout'))
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, ERROR)
service.reset()
action.errors = 2
service.run('start')
self.assertEqual(action.nodes_error(), NodeSet('badname'))
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nodes_timeout(), NodeSet('timeout'))
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, WARNING)
service.reset()
action.errors = 2
action.warnings = 2
service.run('start')
self.assertEqual(action.nodes_error(), NodeSet('badname'))
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nodes_timeout(), NodeSet('timeout'))
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, DONE)
def test_mix_errors_timeout(self):
"""Test the result of mixed timeout and error actions."""
cmd = 'echo "${SSH_CLIENT%%%% *}" | egrep "^(127.0.0.1|::1)$" ||sleep 1'
action = Action(name="start", target="badname,%s,localhost" % HOSTNAME, command=cmd, timeout=0.6)
action.errors = 1
service = Service("test_service")
service.add_action(action)
service.run("start")
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, ERROR)
service.reset()
action.errors = 2
service.run("start")
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, WARNING)
service.reset()
action.errors = 2
action.warnings = 2
service.run("start")
self.assertEqual(action.nb_errors(), 1)
self.assertEqual(action.nb_timeout(), 1)
self.assertEqual(action.status, DONE)
def test_reset_service(self):
'''Test resest values of a service'''
service = Service('brutus')
action = Action('start')
service.origin = True
action.status = DONE
service.add_action(action)
service._last_action = 'start'
service.reset()
self.assertFalse(service.origin)
self.assertFalse(service._last_action)
self.assertEqual(action.status, NO_STATUS)
self.assertEqual(service.status, NO_STATUS)
def test_reset_service(self):
'''Test resest values of a service'''
service = Service('brutus')
action = Action('start')
service.origin = True
action.status = DONE
service.add_action(action)
service._last_action = 'start'
service.reset()
self.assertFalse(service.origin)
self.assertFalse(service._last_action)
self.assertEqual(action.status, NO_STATUS)
self.assertEqual(service.status, NO_STATUS)
def test_nb_errors_local(self):
"""Test the method nb_errors() (local)"""
service = Service('test_service')
act_test = Action(name='test', command='/bin/true')
service.add_action(act_test)
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet())
self.assertEqual(act_test.nb_errors(), 0)
self.assertEqual(act_test.status, DONE)
service.reset()
act_test.errors = 1
act_test.command = '/bin/false'
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, WARNING)
service.reset()
act_test.errors = 1
act_test.warnings = 1
act_test.command = '/bin/false'
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, DONE)
service.reset()
act_test.errors = 0
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, ERROR)
service.reset()
act_test.errors = 0
act_test.warnings = 1
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, ERROR)
def test_nb_errors_local(self):
"""Test the method nb_errors() (local)"""
service = Service('test_service')
act_test = Action(name='test', command='/bin/true')
service.add_action(act_test)
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet())
self.assertEqual(act_test.nb_errors(), 0)
self.assertEqual(act_test.status, DONE)
service.reset()
act_test.errors = 1
act_test.command = '/bin/false'
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, WARNING)
service.reset()
act_test.errors = 1
act_test.warnings = 1
act_test.command = '/bin/false'
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, DONE)
service.reset()
act_test.errors = 0
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, ERROR)
service.reset()
act_test.errors = 0
act_test.warnings = 1
service.run('test')
self.assertEqual(act_test.nodes_error(), NodeSet("localhost"))
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, ERROR)
def test_nb_errors_local(self):
"""Test the method nb_errors() (local)"""
service = Service("test_service")
act_test = Action(name="test", command="/bin/true")
service.add_action(act_test)
service.run("test")
self.assertEqual(act_test.nb_errors(), 0)
self.assertEqual(act_test.status, DONE)
service.reset()
act_test.errors = 1
act_test.command = "/bin/false"
service.run("test")
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, WARNING)
service.reset()
act_test.errors = 1
act_test.warnings = 1
act_test.command = "/bin/false"
service.run("test")
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, DONE)
service.reset()
act_test.errors = 0
service.run("test")
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, ERROR)
service.reset()
act_test.errors = 0
act_test.warnings = 1
service.run("test")
self.assertEqual(act_test.nb_errors(), 1)
self.assertEqual(act_test.status, ERROR)
class ServiceManager(EntityManager):
'''
The service manager has to handle call to services. It implements
features allowing us to get dependencies of service and so on.
'''
def __init__(self):
EntityManager.__init__(self)
# Variables declared in the global scope
self.variables = {}
# Top service
self.source = Service('root')
self.source.simulate = True
def __refresh_graph(self, reverse):
'''Reinitialize the right values for the graph of services'''
for service in self.entities.values():
service.reset()
if reverse:
self.source.clear_child_deps()
else:
self.source.clear_parent_deps()
def has_service(self, service):
'''Determine if the service is registered within the manager'''
return service in self.entities.values()
def has_warnings(self):
'''Determine if the service has one action with the WARNING status'''
for ent in self.entities.values():
if ent.status is WARNING:
return True
return False
def add_var(self, varname, value):
'''Add a symbol within the service manager'''
if varname not in self.variables:
self.variables[varname] = value
else:
raise VariableAlreadyExistError("'%s' already defined" % varname)
def remove_var(self, varname):
'''Remove var from the the service manager'''
if varname in self.variables:
del self.variables[varname]
def reset(self):
'''Clean object service manager.'''
self.variables.clear()
self.entities.clear()
def register_service(self, service):
'''Add a new service to the manager.'''
assert service, 'service added cannot be None'
if service.name in self.entities:
raise ServiceAlreadyReferencedError(service.name)
else:
self.entities[service.name] = service
def register_services(self, *args):
'''Add all services referenced by args'''
for service in args:
self.register_service(service)
def forget_service(self, service):
'''
Remove the service from the manager. It takes care of the relations
with others services in order to avoid to get a graph with a bad format.
'''
assert service, 'The service that you want to forget cannot be None'
if not self.has_service(service):
raise ServiceNotFoundError
else:
dependencies = []
switch = len(service.children)
dependencies.extend(service.children.values())
dependencies.extend(service.parents.values())
for dep in dependencies:
switch -= 1
if switch > 0:
service.remove_dep(dep.target.name, parent=False)
else:
service.remove_dep(dep.target.name)
del self.entities[service.name]
def forget_services(self, *args):
'''Remove all specified services from the manager'''
for service in args:
self.forget_service(service)
def _variable_config(self, conf):
'''Automatic variables based on MilckCheck configuration.'''
if conf:
# -n NODES
self.add_var('SELECTED_NODES', str(conf.get('only_nodes', '')))
# -x NODES
self.add_var('EXCLUDED_NODES', str(conf.get('excluded_nodes', '')))
# Add command line variable
for defines in conf.get('defines', []):
for define in defines.split():
key, value = define.split('=', 1)
self.add_var(key, value)
else:
for varname in ('selected_node', 'excluded_nodes'):
self.add_var(varname.upper(), '')
def _apply_config(self, conf):
'''
This apply a sequence of modifications on the graph. A modification
can be an update of the nodes usable by the services or whatever that
is referenced within configuration.
'''
# Load the configuration located within the directory
if conf.get('config_dir'):
self.entities.clear()
self.load_config(conf['config_dir'])
# Avoid some of the services referenced in the graph
if conf.get('excluded_svc'):
self.__lock_services(conf['excluded_svc'])
# Use just those nodes
if conf.get('only_nodes') is not None:
self.__update_usable_nodes(conf['only_nodes'], 'INT')
# Avoid those nodes
elif conf.get('excluded_nodes') is not None:
self.__update_usable_nodes(conf['excluded_nodes'], 'DIF')
def __lock_services(self, services):
'''
Lock all services specified in the list. This will assign the LOCKED
status on the services. A soon as a service is locked it will never be
processed.
'''
for service in services:
if service in self.entities:
self.entities[service].status = LOCKED
def _lock_services_except(self, services):
"""Lock all services except those provided."""
for service in self.entities:
if service not in services:
self.entities[service].status = LOCKED
def __update_usable_nodes(self, nodeset, mode=None):
'''
Update target value used by the service and the elements linked to
the service.
'''
assert mode in (None, 'DIF', 'INT'), \
'Invalid mode, should be DIF, INT or None'
for service in self.entities.values():
service.update_target(nodeset, mode)
def call_services(self, services, action, conf=None):
'''Allow the user to call one or multiple services.'''
assert action, 'action name cannot be None'
# Manage reverse mode based on configuration
reverse = False
if conf:
reverse = action in conf.get('reverse_actions')
self.variables.clear()
# Create global variable from configuration
self._variable_config(conf)
# Make sure that the graph is usable
self.__refresh_graph(reverse)
# Apply configuration over the graph
if conf:
self._apply_config(conf)
self.source.reset()
# Enable reverse mode if needed
self._reverse_mod(reverse)
self.source.algo_reversed = reverse
if not self.source.has_action(action):
self.source.add_action(Action(name=action, command=':'))
# Perform all services
if not services:
for service in self.entities.values():
if reverse and not service.parents:
service.add_dep(target=self.source)
elif not reverse and not service.children:
self.source.add_dep(target=service)
# Perform required services
else:
for service_name in services:
if service_name in self.entities:
if reverse:
self.entities[service_name].add_dep(target=self.source)
else:
self.source.add_dep(target=self.entities[service_name])
else:
raise ServiceNotFoundError('Undefined service [%s]'
% service_name)
if conf and conf.get('nodeps'):
self._lock_services_except(self.source.deps().keys())
self.source.run(action)
def output_graph(self, services=None, excluded=None):
"""Return entities graph (DOT format)"""
grph = "digraph dependency {\n"
grph += "compound=true;\n"
#grph += "node [shape=circle];\n"
grph += "node [style=filled];\n"
for service in (services or self.entities):
if not self.entities[service].excluded(excluded):
grph += self.entities[service].graph(excluded)
grph += '}\n'
return grph
def load_config(self, conf):
'''
Load the configuration within the manager thanks to MilkCheckConfig
'''
from MilkCheck.Config.Configuration import MilkCheckConfig
config = MilkCheckConfig()
config.load_from_dir(directory=conf)
config.build_graph()
class ServiceGroup(Service):
"""
This class models a group of service. A group of service
can own actions it's no mandatory. However it shall have
subservices
"""
def __init__(self, name, target=None):
Service.__init__(self, name, target)
# Entry point of the group
self._source = Service('source')
self._source.simulate = True
self._source.add_dep(target=self, parent=False)
del self.parents['source']
self._sink = Service('sink')
self._sink.simulate = True
# subservices
self._subservices = {}
def update_target(self, nodeset, mode=None):
'''Update the attribute target of a ServiceGroup'''
BaseEntity.update_target(self, nodeset, mode)
for service in self._subservices.values():
service.update_target(nodeset, mode)
def filter_nodes(self, nodes):
"""
Add error nodes to skip list.
Nodes in this list will not be used when launching actions.
"""
BaseEntity.filter_nodes(self, nodes)
for service in self._subservices.values():
service.filter_nodes(nodes)
def iter_subservices(self):
'''Return an iterator over the subservices'''
return self._subservices.itervalues()
def reset(self):
'''Reset values of attributes in order to perform multiple exec'''
Service.reset(self)
for service in self._subservices.values():
service.reset()
self._sink.reset()
self._source.reset()
def search(self, name, reverse=False):
"""Look for a node through the overall graph"""
target = None
if reverse:
target = self._sink.search(name, reverse)
else:
target = self._source.search(name)
if target:
return target
else:
return Service.search(self, name, reverse)
def has_subservice(self, name):
"""
Check if the service is referenced within the group
"""
return name in self._subservices
def has_action(self, action_name):
"""
A group consider to get an action only if both source and sink
own the action
"""
for svc in self.iter_subservices():
if svc.has_action(action_name):
return True
return False
def skip(self):
"""Skip all services from this group"""
for svc in self.iter_subservices():
svc.skip()
def to_skip(self, action):
"""
Tell if group should be skipped for provided action name.
That means that all its subservices should be skipped.
"""
for svc in self._subservices.values():
if not svc.to_skip(action):
return False
return True
def add_inter_dep(self, target, base=None, sgth=REQUIRE):
"""
Add dependency in the subgraph. Adding a dependency in using this
method means that the target will be an internal dependency of the
group
"""
if base and not self.has_subservice(base.name):
raise ServiceNotFoundError()
# A base node is specified so hook target on it
if base:
if not target.has_parent_dep('sink'):
target.add_dep(target=self._sink)
if not target.children:
target.add_dep(target=self._source, parent=False)
base.add_dep(target=target, sgth=sgth)
# Target is hooked on source and sink
else:
self._sink.add_dep(target=target, sgth=sgth, parent=False)
self._source.add_dep(target=target, sgth=sgth)
self._subservices[target.name] = target
target.parent = self
self.__update_edges()
def __update_edges(self, create_links=False):
'''Update edges of the subgraph'''
for abs_ser in (self._source, self._sink):
if create_links:
for service in self._subservices.values():
if not service.parents:
self._sink.add_dep(target=service, parent=False)
if not service.children:
self._source.add_dep(target=service)
else:
if abs_ser is self._source:
deps = abs_ser.parents
else:
deps = abs_ser.children
for dep in deps.values():
# If direct dependency of source have more than one child
# remove this dependency
if abs_ser is self._source and len(dep.target.children) > 1:
dep.target.remove_dep('source', parent=False)
# If direct dependency of source have more than one parent
# remove this dependency
elif abs_ser is self._sink and len(dep.target.parents) > 1:
dep.target.remove_dep('sink')
def remove_inter_dep(self, dep_name):
"""
Remove a dependency on both side, in the current object and in the
target object concerned by the dependency
"""
if not self.has_subservice(dep_name):
raise ServiceNotFoundError()
else:
for dep in self._subservices[dep_name].parents.values():
dep.target.remove_dep(dep_name, parent=False)
for dep in self._subservices[dep_name].children.values():
dep.target.remove_dep(dep_name)
del self._subservices[dep_name]
self.__update_edges(True)
def graph_info(self):
""" Return a tuple to manage dependencies output """
return ("%s.__hook" % self.fullname(), "cluster_%s" % self.fullname())
def graph(self, excluded=None):
""" Generate a subgraph of dependencies in the ServiceGroup"""
grph = ''
grph += 'subgraph "cluster_%s" {\nlabel="%s";\n' % (self.fullname(),
self.fullname())
grph += 'style=rounded;\nnode [style=filled];\n'
# Create a default node to manage DOT output
# __hook will be used to attach the nodes to the subgraph
grph += '"%s.__hook" [style=invis];\n' % self.fullname()
# Graph content of the servicegroup
entities = self._subservices
for ent in entities.values():
if not ent.excluded(excluded):
grph += ent.graph(excluded=excluded)
grph += '}\n'
# Graph dependencies of the service group
for dep in self.deps().values():
if not dep.target.excluded(excluded):
if not dep.target.simulate:
grph += dep.graph(self)
return grph
def eval_deps_status(self):
"""
Evaluate the result of the dependencies in order to check
if we have to continue in normal mode or in a degraded mode.
"""
extd_status = Service.eval_deps_status(self)
intd_status = DONE
if self._algo_reversed:
intd_status = self._sink.eval_deps_status()
else:
intd_status = self._source.eval_deps_status()
if DEP_ORDER[extd_status] > DEP_ORDER[intd_status]:
return extd_status
else:
return intd_status
def _launch_action(self, action, status):
"""
ServiceGroup does not have real action, but internal services instead.
Launch internal services if needed or just set group status.
Group status is based on its internal status.
"""
# Check if the action is MISSING in the whole group.
if not self.has_action(action):
self.update_status(MISSING)
# Check if the whole group is SKIPPED
elif self.to_skip(action):
self.update_status(SKIPPED)
# If there is a dep error, we should not run anything
elif status == DEP_ERROR:
self.update_status(DEP_ERROR)
# No dep error, try to run internal services
elif self._algo_reversed and self._sink.children and \
self._sink.status is NO_STATUS:
self._sink.prepare(action)
elif not self._algo_reversed and self._source.parents and \
self._source.status is NO_STATUS:
self._source.prepare(action)
# No service to run, just update status
else:
if self._algo_reversed:
intd_status = self._sink.eval_deps_status()
else:
intd_status = self._source.eval_deps_status()
self.update_status(intd_status)
def inherits_from(self, entity):
'''Inherit properties from entity'''
BaseEntity.inherits_from(self, entity)
for subservice in self.iter_subservices():
subservice.inherits_from(self)
def set_algo_reversed(self, flag):
"""Updates dependencies if reversed flag is specified"""
if self._algo_reversed and not flag:
del self._sink.parents[self.name]
self._source.add_dep(target=self, parent=False)
del self.parents['source']
elif not self._algo_reversed and flag:
del self._source.children[self.name]
self._sink.add_dep(target=self)
del self.children['sink']
for service in self._subservices.values():
service.algo_reversed = flag
self._algo_reversed = flag
self._sink._algo_reversed = flag
self._source._algo_reversed = flag
algo_reversed = property(fset=set_algo_reversed)
def fromdict(self, grpdict):
"""Populate group attributes from dict."""
BaseEntity.fromdict(self, grpdict)
if 'services' in grpdict:
dep_mapping = {}
# Wrap dependencies from YAML and build the service
for names, props in grpdict['services'].items():
for subservice in NodeSet(names):
# Parsing dependencies
wrap = DepWrapper()
for prop in ('require', 'require_weak', 'require_filter',
'filter', 'before', 'after', 'check'):
if prop in props:
if prop in ('before', 'after'):
props['require_weak'] = props[prop]
prop = 'require_weak'
# Only for compat with v1.1beta versions
if prop == 'require_filter':
props['filter'] = props[prop]
prop = 'filter'
wrap.deps[prop] = props[prop]
# Get subservices which might be Service or ServiceGroup
service = None
if 'services' in props:
service = ServiceGroup(subservice)
else:
service = Service(subservice)
# Link the group and its new subservice together
self._subservices[subservice] = service
service.parent = self
# Populate based on dict content
service.fromdict(props)
wrap.source = service
dep_mapping[subservice] = wrap
# Generate dependency links of the service
for wrap in dep_mapping.values():
# Not any dependencies so just attach
for dtype in wrap.deps:
wrap.deps[dtype] = wrap.source._resolve(wrap.deps[dtype])
# For simplicity, supports deps as a single service
if type(wrap.deps[dtype]) is str:
wrap.deps[dtype] = [wrap.deps[dtype]]
for dep in wrap.deps[dtype]:
if dep not in self._subservices:
raise UnknownDependencyError(dep)
wrap.source.add_dep(self._subservices[dep],
sgth=dtype.upper())
# Bind subgraph to the service group
for service in self.iter_subservices():
if not service.children:
service.add_dep(self._source, parent=False)
if not service.parents:
service.add_dep(self._sink)
for subser in self.iter_subservices():
subser.inherits_from(self)
def resolve_all(self):
"""Resolve all variables in ServiceGroup properties"""
BaseEntity.resolve_all(self)
for subser in self.iter_subservices():
subser.resolve_all()
class ServiceGroup(Service):
"""
This class models a group of service. A group of service
can own actions it's no mandatory. However it shall have
subservices
"""
def __init__(self, name, target=None):
Service.__init__(self, name, target)
# Entry point of the group
self._source = Service('source')
self._source.simulate = True
self._source.add_dep(target=self, parent=False)
del self.parents['source']
self._sink = Service('sink')
self._sink.simulate = True
# subservices
self._subservices = {}
def update_target(self, nodeset, mode=None):
'''Update the attribute target of a ServiceGroup'''
BaseEntity.update_target(self, nodeset, mode)
for service in self._subservices.values():
service.update_target(nodeset, mode)
def iter_subservices(self):
'''Return an iterator over the subservices'''
return self._subservices.itervalues()
def reset(self):
'''Reset values of attributes in order to perform multiple exec'''
Service.reset(self)
for service in self._subservices.values():
service.reset()
self._sink.reset()
self._source.reset()
def search(self, name, reverse=False):
"""Look for a node through the overall graph"""
target = None
if reverse:
target = self._sink.search(name, reverse)
else:
target = self._source.search(name)
if target:
return target
else:
return Service.search(self, name, reverse)
def has_subservice(self, name):
"""
Check if the service is referenced within the group
"""
return name in self._subservices
def has_action(self, action_name):
"""
A group consider to get an action only if both source and sink
own the action
"""
for svc in self.iter_subservices():
if svc.has_action(action_name):
return True
return False
def to_skip(self, action):
"""
Tell if group should be skipped for provided action name.
That means that all its subservices should be skipped.
"""
for svc in self._subservices.values():
if not svc.to_skip(action):
return False
return True
def add_inter_dep(self, target, base=None, sgth=REQUIRE):
"""
Add dependency in the subgraph. Adding a dependency in using this
method means that the target will be an internal dependency of the
group
"""
if base and not self.has_subservice(base.name):
raise ServiceNotFoundError()
# A base node is specified so hook target on it
if base:
if not target.has_parent_dep('sink'):
target.add_dep(target=self._sink)
if not target.children:
target.add_dep(target=self._source, parent=False)
base.add_dep(target=target, sgth=sgth)
# Target is hooked on source and sink
else:
self._sink.add_dep(target=target, sgth=sgth, parent=False)
self._source.add_dep(target=target, sgth=sgth)
self._subservices[target.name] = target
target.parent = self
self.__update_edges()
def __update_edges(self, create_links=False):
'''Update edges of the subgraph'''
for abs_ser in (self._source, self._sink):
if create_links:
for service in self._subservices.values():
if not service.parents:
self._sink.add_dep(target=service, parent=False)
if not service.children:
self._source.add_dep(target=service)
else:
if abs_ser is self._source:
deps = abs_ser.parents
else:
deps = abs_ser.children
for dep in deps.values():
# If direct dependency of source have more than one child
# remove this dependency
if abs_ser is self._source and len(dep.target.children) > 1:
dep.target.remove_dep('source', parent=False)
# If direct dependency of source have more than one parent
# remove this dependency
elif abs_ser is self._sink and len(dep.target.parents) > 1:
dep.target.remove_dep('sink')
def remove_inter_dep(self, dep_name):
"""
Remove a dependency on both side, in the current object and in the
target object concerned by the dependency
"""
if not self.has_subservice(dep_name):
raise ServiceNotFoundError()
else:
for dep in self._subservices[dep_name].parents.values():
dep.target.remove_dep(dep_name, parent=False)
for dep in self._subservices[dep_name].children.values():
dep.target.remove_dep(dep_name)
del self._subservices[dep_name]
self.__update_edges(True)
def graph_info(self):
""" Return a tuple to manage dependencies output """
return ("%s.__hook" % self.fullname(), "cluster_%s" % self.fullname())
def graph(self, excluded=None):
""" Generate a subgraph of dependencies in the ServiceGroup"""
grph = ''
grph += 'subgraph "cluster_%s" {\nlabel="%s";\n' % (self.fullname(),
self.fullname())
grph += 'style=rounded;\nnode [style=filled];\n'
# Create a default node to manage DOT output
# __hook will be used to attach the nodes to the subgraph
grph += '"%s.__hook" [style=invis];\n' % self.fullname()
# Graph content of the servicegroup
entities = self._subservices
for ent in entities.values():
if not ent.excluded(excluded):
grph += ent.graph(excluded=excluded)
grph += '}\n'
# Graph dependencies of the service group
for dep in self.deps().values():
if not dep.target.excluded(excluded):
if not dep.target.simulate:
grph += dep.graph(self)
return grph
def eval_deps_status(self):
"""
Evaluate the result of the dependencies in order to check
if we have to continue in normal mode or in a degraded mode.
"""
extd_status = Service.eval_deps_status(self)
intd_status = DONE
if self._algo_reversed:
intd_status = self._sink.eval_deps_status()
else:
intd_status = self._source.eval_deps_status()
if DEP_ORDER[extd_status] > DEP_ORDER[intd_status]:
return extd_status
else:
return intd_status
def _launch_action(self, action, status):
"""
ServiceGroup does not have real action, but internal services instead.
Launch internal services if needed or just set group status.
Group status is based on its internal status.
"""
# Check if the action is MISSING in the whole group.
if not self.has_action(action):
self.update_status(MISSING)
# Check if the whole group is SKIPPED
elif self.to_skip(action):
self.update_status(SKIPPED)
# If there is a dep error, we should not run anything
elif status == DEP_ERROR:
self.update_status(DEP_ERROR)
# No dep error, try to run internal services
elif self._algo_reversed and self._sink.children and \
self._sink.status is NO_STATUS:
self._sink.prepare(action)
elif not self._algo_reversed and self._source.parents and \
self._source.status is NO_STATUS:
self._source.prepare(action)
# No service to run, just update status
else:
if self._algo_reversed:
intd_status = self._sink.eval_deps_status()
else:
intd_status = self._source.eval_deps_status()
self.update_status(intd_status)
def inherits_from(self, entity):
'''Inherit properties from entity'''
BaseEntity.inherits_from(self, entity)
for subservice in self.iter_subservices():
subservice.inherits_from(self)
def set_algo_reversed(self, flag):
"""Updates dependencies if reversed flag is specified"""
if self._algo_reversed and not flag:
del self._sink.parents[self.name]
self._source.add_dep(target=self, parent=False)
del self.parents['source']
elif not self._algo_reversed and flag:
del self._source.children[self.name]
self._sink.add_dep(target=self)
del self.children['sink']
for service in self._subservices.values():
service.algo_reversed = flag
self._algo_reversed = flag
self._sink._algo_reversed = flag
self._source._algo_reversed = flag
algo_reversed = property(fset=set_algo_reversed)
def fromdict(self, grpdict):
"""Populate group attributes from dict."""
BaseEntity.fromdict(self, grpdict)
if 'services' in grpdict:
dep_mapping = {}
# Wrap dependencies from YAML and build the service
for names, props in grpdict['services'].items():
for subservice in NodeSet(names):
# Parsing dependencies
wrap = DepWrapper()
for prop in ('require', 'require_weak',
'before', 'after', 'check'):
if prop in props:
if prop in ('before', 'after'):
props['require_weak'] = props[prop]
prop = 'require_weak'
wrap.deps[prop] = props[prop]
# Get subservices which might be Service or ServiceGroup
service = None
if 'services' in props:
service = ServiceGroup(subservice)
service.fromdict(props)
else:
service = Service(subservice)
service.fromdict(props)
# Link the group and its new subservice together
self._subservices[subservice] = service
service.parent = self
wrap.source = service
dep_mapping[subservice] = wrap
# Generate dependency links of the service
for wrap in dep_mapping.values():
# Not any dependencies so just attach
for dtype in wrap.deps:
for dep in wrap.deps[dtype]:
if dep not in self._subservices:
raise UnknownDependencyError(dep)
wrap.source.add_dep(self._subservices[dep],
sgth=dtype.upper())
# Bind subgraph to the service group
for service in self.iter_subservices():
if not service.children:
service.add_dep(self._source, parent=False)
if not service.parents:
service.add_dep(self._sink)
for subser in self.iter_subservices():
subser.inherits_from(self)
class ServiceManager(EntityManager):
'''
The service manager has to handle call to services. It implements
features allowing us to get dependencies of service and so on.
'''
def __init__(self):
EntityManager.__init__(self)
# Variables declared in the global scope
self.variables = {}
# Top service
self.source = Service('root')
self.source.simulate = True
def __refresh_graph(self, reverse):
'''Reinitialize the right values for the graph of services'''
for service in self.entities.values():
service.reset()
if reverse:
self.source.clear_child_deps()
else:
self.source.clear_parent_deps()
def has_service(self, service):
'''Determine if the service is registered within the manager'''
return service in self.entities.values()
def has_warnings(self):
'''Determine if the service has one action with the WARNING status'''
for ent in self.entities.values():
if ent.status is WARNING:
return True
return False
def add_var(self, varname, value):
'''Add a symbol within the service manager'''
if varname not in self.variables:
self.variables[varname] = value
else:
raise VariableAlreadyExistError("'%s' already defined" % varname)
def remove_var(self, varname):
'''Remove var from the the service manager'''
if varname in self.variables:
del self.variables[varname]
def reset(self):
'''Clean object service manager.'''
self.variables.clear()
self.entities.clear()
def register_service(self, service):
'''Add a new service to the manager.'''
assert service, 'service added cannot be None'
if service.name in self.entities:
raise ServiceAlreadyReferencedError(service.name)
else:
self.entities[service.name] = service
def register_services(self, *args):
'''Add all services referenced by args'''
for service in args:
self.register_service(service)
def forget_service(self, service):
'''
Remove the service from the manager. It takes care of the relations
with others services in order to avoid to get a graph with a bad format.
'''
assert service, 'The service that you want to forget cannot be None'
if not self.has_service(service):
raise ServiceNotFoundError
else:
dependencies = []
switch = len(service.children)
dependencies.extend(service.children.values())
dependencies.extend(service.parents.values())
for dep in dependencies:
switch -= 1
if switch > 0:
service.remove_dep(dep.target.name, parent=False)
else:
service.remove_dep(dep.target.name)
del self.entities[service.name]
def forget_services(self, *args):
'''Remove all specified services from the manager'''
for service in args:
self.forget_service(service)
def _variable_config(self, conf):
'''Automatic variables based on MilckCheck configuration.'''
if conf:
# -n NODES
self.add_var('SELECTED_NODES', str(conf.get('only_nodes', '')))
# -x NODES
self.add_var('EXCLUDED_NODES', str(conf.get('excluded_nodes', '')))
# Add command line variable
for defines in conf.get('defines', []):
for define in defines.split():
key, value = define.split('=', 1)
self.add_var(key, value)
else:
for varname in ('selected_node', 'excluded_nodes'):
self.add_var(varname.upper(), '')
def _apply_config(self, conf):
'''
This apply a sequence of modifications on the graph. A modification
can be an update of the nodes usable by the services or whatever that
is referenced within configuration.
'''
# Load the configuration located within the directory
if conf.get('config_dir'):
self.entities.clear()
self.load_config(conf['config_dir'])
# Avoid some of the services referenced in the graph
if conf.get('excluded_svc'):
self.__lock_services(conf['excluded_svc'])
# Use just those nodes
if conf.get('only_nodes') is not None:
self.__update_usable_nodes(conf['only_nodes'], 'INT')
# Avoid those nodes
elif conf.get('excluded_nodes') is not None:
self.__update_usable_nodes(conf['excluded_nodes'], 'DIF')
def __lock_services(self, services):
'''
Lock all services specified in the list. This will assign the LOCKED
status on the services. A soon as a service is locked it will never be
processed.
'''
for service in services:
if service in self.entities:
self.entities[service].status = LOCKED
def _lock_services_except(self, services):
"""Lock all services except those provided."""
for service in self.entities:
if service not in services:
self.entities[service].status = LOCKED
def __update_usable_nodes(self, nodeset, mode=None):
'''
Update target value used by the service and the elements linked to
the service.
'''
assert mode in (None, 'DIF', 'INT'), \
'Invalid mode, should be DIF, INT or None'
for service in self.entities.values():
service.update_target(nodeset, mode)
def call_services(self, services, action, conf=None):
'''Allow the user to call one or multiple services.'''
assert action, 'action name cannot be None'
# Manage reverse mode based on configuration
reverse = False
if conf:
reverse = action in conf.get('reverse_actions')
self.variables.clear()
# Create global variable from configuration
self._variable_config(conf)
# Make sure that the graph is usable
self.__refresh_graph(reverse)
# Apply configuration over the graph
if conf:
self._apply_config(conf)
self.source.reset()
# Enable reverse mode if needed
self._reverse_mod(reverse)
self.source.algo_reversed = reverse
if not self.source.has_action(action):
self.source.add_action(Action(name=action, command=':'))
# Perform all services
if not services:
for service in self.entities.values():
if reverse and not service.parents:
service.add_dep(target=self.source)
elif not reverse and not service.children:
self.source.add_dep(target=service)
# Perform required services
else:
for service_name in services:
if service_name in self.entities:
if reverse:
self.entities[service_name].add_dep(target=self.source)
else:
self.source.add_dep(target=self.entities[service_name])
else:
raise ServiceNotFoundError('Undefined service [%s]' %
service_name)
if conf and conf.get('nodeps'):
self._lock_services_except(self.source.deps().keys())
self.source.run(action)
def output_graph(self, services=None, excluded=None):
"""Return entities graph (DOT format)"""
grph = "digraph dependency {\n"
grph += "compound=true;\n"
#grph += "node [shape=circle];\n"
grph += "node [style=filled];\n"
for service in (services or self.entities):
if not self.entities[service].excluded(excluded):
grph += self.entities[service].graph(excluded)
grph += '}\n'
return grph
def load_config(self, conf):
'''
Load the configuration within the manager thanks to MilkCheckConfig
'''
from MilkCheck.Config.Configuration import MilkCheckConfig
config = MilkCheckConfig()
config.load_from_dir(directory=conf)
config.build_graph()
