from __future__ import absolute_import, unicode_literals from logging import getLogger from django.db.models import ( CharField, IntegerField, ForeignKey, BooleanField, ManyToManyField, FloatField, permalink, ) from django.utils.translation import ugettext_lazy as _ from celery.exceptions import TimeoutError from model_utils.models import TimeStampedModel from taggit.managers import TaggableManager from common.models import method_cache, WorkerNotFound from firewall.models import Host from ..tasks import vm_tasks from .common import Trait from .activity import node_activity, NodeActivity from monitor.calvin.calvin import Query from monitor.calvin.calvin import GraphiteHandler from django.utils import timezone logger = getLogger(__name__) def node_available(function): """Decorate methods to ignore disabled Nodes. """ def decorate(self, *args, **kwargs): if self.enabled and self.online: return function(self, *args, **kwargs) else: return None return decorate class Node(TimeStampedModel): """A VM host machine, a hypervisor. """ name = CharField(max_length=50, unique=True, verbose_name=_('name'), help_text=_('Human readable name of node.')) priority = IntegerField(verbose_name=_('priority'), help_text=_('Node usage priority.')) host = ForeignKey(Host, verbose_name=_('host'), help_text=_('Host in firewall.')) enabled = BooleanField(verbose_name=_('enabled'), default=False, help_text=_('Indicates whether the node can ' 'be used for hosting.')) traits = ManyToManyField(Trait, blank=True, help_text=_("Declared traits."), verbose_name=_('traits')) tags = TaggableManager(blank=True, verbose_name=_("tags")) overcommit = FloatField(default=1.0, verbose_name=_("overcommit ratio"), help_text=_("The ratio of total memory with " "to without overcommit.")) class Meta: app_label = 'vm' db_table = 'vm_node' permissions = () def __unicode__(self): return self.name @method_cache(10) def get_online(self): """Check if the node is online. Check if node is online by queue is available. """ try: self.get_remote_queue_name("vm") except: return False else: return True online = property(get_online) @node_available @method_cache(300) def get_num_cores(self): """Number of CPU threads available to the virtual machines. """ return self.remote_query(vm_tasks.get_core_num, default=0) num_cores = property(get_num_cores) STATES = {False: {False: ('OFFLINE', _('offline')), True: ('DISABLED', _('disabled'))}, True: {False: ('MISSING', _('missing')), True: ('ONLINE', _('online'))}} def get_state(self): """The state combined of online and enabled attributes. """ return self.STATES[self.enabled][self.online][0] state = property(get_state) def get_status_display(self): return self.STATES[self.enabled][self.online][1] def disable(self, user=None): ''' Disable the node.''' if self.enabled: with node_activity(code_suffix='disable', node=self, user=user): self.enabled = False self.save() def enable(self, user=None): ''' Enable the node. ''' if self.enabled is not True: with node_activity(code_suffix='enable', node=self, user=user): self.enabled = True self.save() self.get_num_cores(invalidate_cache=True) self.get_ram_size(invalidate_cache=True) @node_available @method_cache(300) def get_ram_size(self): """Bytes of total memory in the node. """ return self.remote_query(vm_tasks.get_ram_size, default=0) ram_size = property(get_ram_size) @property @node_available def ram_size_with_overcommit(self): """Bytes of total memory including overcommit margin. """ return self.ram_size * self.overcommit @method_cache(30) def get_remote_queue_name(self, queue_id): """Return the name of the remote celery queue for this node. throws Exception if there is no worker on the queue. Until the cache provide reult there can be dead queues. """ if vm_tasks.check_queue(self.host.hostname, queue_id): self.node_online() return self.host.hostname + "." + queue_id else: if self.enabled: self.node_offline() raise WorkerNotFound() def node_online(self): """Create activity and log entry when node reappears. """ try: act = self.activity_log.order_by('-pk')[0] except IndexError: pass # no monitoring activity at all else: logger.debug("The last activity was %s" % act) if act.activity_code.endswith("offline"): act = NodeActivity.create(code_suffix='monitor_succes_online', node=self, user=None) act.started = timezone.now() act.finished = timezone.now() act.succeeded = True act.save() logger.info("Node %s is ONLINE." % self.name) self.get_num_cores(invalidate_cache=True) self.get_ram_size(invalidate_cache=True) def node_offline(self): """Called when a node disappears. If the node is not already offline, record an activity and a log entry. """ try: act = self.activity_log.order_by('-pk')[0] except IndexError: pass # no activity at all else: logger.debug("The last activity was %s" % act) if act.activity_code.endswith("offline"): return act = NodeActivity.create(code_suffix='monitor_failed_offline', node=self, user=None) act.started = timezone.now() act.finished = timezone.now() act.succeeded = False act.save() logger.critical("Node %s is OFFLINE%s.", self.name, ", but enabled" if self.enabled else "") # TODO: check if we should reschedule any VMs? def remote_query(self, task, timeout=30, raise_=False, default=None): """Query the given task, and get the result. If the result is not ready or worker not reachable in timeout secs, return default value or raise a TimeoutError or WorkerNotFound exception. """ try: r = task.apply_async( queue=self.get_remote_queue_name('vm'), expires=timeout + 60) return r.get(timeout=timeout) except (TimeoutError, WorkerNotFound): if raise_: raise else: return default @node_available def get_monitor_info(self): try: handler = GraphiteHandler() except RuntimeError: return self.remote_query(vm_tasks.get_node_metrics, 30) query = Query() query.set_target(self.host.hostname + ".circle") query.set_format("json") query.set_relative_start(5, "minutes") metrics = ["cpu.usage", "memory.usage"] for metric in metrics: query.set_metric(metric) query.generate() handler.put(query) handler.send() collected = {} for metric in metrics: response = handler.pop() try: cache = response[0]["datapoints"][-1][0] except (IndexError, KeyError): cache = 0 if cache is None: cache = 0 collected[metric] = cache return collected @property @node_available def cpu_usage(self): return float(self.get_monitor_info()["cpu.usage"]) / 100 @property @node_available def ram_usage(self): return float(self.get_monitor_info()["memory.usage"]) / 100 @property @node_available def byte_ram_usage(self): return self.ram_usage * self.ram_size @node_available def update_vm_states(self): """Update state of Instances running on this Node. Query state of all libvirt domains, and notify Instances by their vm_state_changed hook. """ domains = {} domain_list = self.remote_query(vm_tasks.list_domains_info, timeout=5) if domain_list is None: logger.info("Monitoring failed at: %s", self.name) return for i in domain_list: # [{'name': 'cloud-1234', 'state': 'RUNNING', ...}, ...] try: id = int(i['name'].split('-')[1]) except: pass # name format doesn't match else: domains[id] = i['state'] instances = [{'id': i.id, 'state': i.state} for i in self.instance_set.order_by('id').all()] for i in instances: try: d = domains[i['id']] except KeyError: logger.info('Node %s update: instance %s missing from ' 'libvirt', self, i['id']) # Set state to STOPPED when instance is missing self.instance_set.get(id=i['id']).vm_state_changed('STOPPED') else: if d != i['state']: logger.info('Node %s update: instance %s state changed ' '(libvirt: %s, db: %s)', self, i['id'], d, i['state']) self.instance_set.get(id=i['id']).vm_state_changed(d) del domains[i['id']] for i in domains.keys(): logger.info('Node %s update: domain %s in libvirt but not in db.', self, i) @classmethod def get_state_count(cls, online, enabled): return len([1 for i in cls.objects.filter(enabled=enabled).select_related('host') if i.online == online]) @permalink def get_absolute_url(self): return ('dashboard.views.node-detail', None, {'pk': self.id})