django-orchestra/orchestra/apps/orchestration/models.py

180 lines
6.1 KiB
Python

from django.contrib.contenttypes import generic
from django.contrib.contenttypes.models import ContentType
from django.core.exceptions import ValidationError
from django.db import models
from django.utils.translation import ugettext_lazy as _
from orchestra.utils.apps import autodiscover
from . import settings, manager
from .backends import ServiceBackend
class Server(models.Model):
""" Machine runing daemons (services) """
name = models.CharField(_("name"), max_length=256, unique=True)
# TODO unique address with blank=True (nullablecharfield)
address = models.CharField(_("address"), max_length=256, blank=True,
help_text=_("IP address or domain name"))
description = models.TextField(_("description"), blank=True)
os = models.CharField(_("operative system"), max_length=32,
choices=settings.ORCHESTRATION_OS_CHOICES,
default=settings.ORCHESTRATION_DEFAULT_OS)
def __unicode__(self):
return self.name
def get_address(self):
if self.address:
return self.address
return self.name
class BackendLog(models.Model):
RECEIVED = 'RECEIVED'
TIMEOUT = 'TIMEOUT'
STARTED = 'STARTED'
SUCCESS = 'SUCCESS'
FAILURE = 'FAILURE'
ERROR = 'ERROR'
REVOKED = 'REVOKED'
STATES = (
(RECEIVED, RECEIVED),
(TIMEOUT, TIMEOUT),
(STARTED, STARTED),
(SUCCESS, SUCCESS),
(FAILURE, FAILURE),
(ERROR, ERROR),
(REVOKED, REVOKED),
)
backend = models.CharField(_("backend"), max_length=256)
state = models.CharField(_("state"), max_length=16, choices=STATES,
default=RECEIVED)
server = models.ForeignKey(Server, verbose_name=_("server"),
related_name='execution_logs')
script = models.TextField(_("script"))
stdout = models.TextField()
stderr = models.TextField()
traceback = models.TextField(_("traceback"))
exit_code = models.IntegerField(_("exit code"), null=True)
task_id = models.CharField(_("task ID"), max_length=36, unique=True, null=True,
help_text="Celery task ID")
created = models.DateTimeField(_("created"), auto_now_add=True)
last_update = models.DateTimeField(_("last update"), auto_now=True)
class Meta:
get_latest_by = 'created'
@property
def execution_time(self):
return (self.last_update-self.created).total_seconds()
class BackendOperation(models.Model):
"""
Encapsulates an operation, storing its related object, the action and the backend.
"""
SAVE = 'save'
DELETE = 'delete'
ACTIONS = (
(SAVE, _("save")),
(DELETE, _("delete")),
)
log = models.ForeignKey('orchestration.BackendLog', related_name='operations')
backend_class = models.CharField(_("backend"), max_length=256)
action = models.CharField(_("action"), max_length=64, choices=ACTIONS)
content_type = models.ForeignKey(ContentType)
object_id = models.PositiveIntegerField()
instance = generic.GenericForeignKey('content_type', 'object_id')
class Meta:
verbose_name = _("Operation")
verbose_name_plural = _("Operations")
def __unicode__(self):
return '%s.%s(%s)' % (self.backend_class, self.action, self.instance)
def __hash__(self):
""" set() """
backend = getattr(self, 'backend', self.backend_class)
return hash(backend) + hash(self.instance) + hash(self.action)
def __eq__(self, operation):
""" set() """
return hash(self) == hash(operation)
@classmethod
def create(cls, backend, instance, action):
op = cls(backend_class=backend.get_name(), instance=instance, action=action)
op.backend = backend
return op
@classmethod
def execute(cls, operations):
return manager.execute(operations)
autodiscover('backends')
class Route(models.Model):
"""
Defines the routing that determine in which server a backend is executed
"""
backend = models.CharField(_("backend"), max_length=256,
choices=ServiceBackend.get_choices())
host = models.ForeignKey(Server, verbose_name=_("host"))
match = models.CharField(_("match"), max_length=256, blank=True, default='True',
help_text=_("Python expression used for selecting the targe host, "
"<em>instance</em> referes to the current object."))
# async = models.BooleanField(default=False)
# method = models.CharField(_("method"), max_lenght=32, choices=method_choices,
# default=MethodBackend.get_default())
is_active = models.BooleanField(_("is active"), default=True)
class Meta:
unique_together = ('backend', 'host')
def __unicode__(self):
return "%s@%s" % (self.backend, self.host)
# def clean(self):
# backend, method = self.get_backend_class(), self.get_method_class()
# if not backend.type in method.types:
# msg = _("%s backend is not compatible with %s method")
# raise ValidationError(msg % (self.backend, self.method)
@classmethod
def get_servers(cls, operation):
backend_name = operation.backend.get_name()
try:
routes = cls.objects.filter(is_active=True, backend=backend_name)
except cls.DoesNotExist:
return []
safe_locals = { 'instance': operation.instance }
pks = [ route.pk for route in routes.all() if eval(route.match, safe_locals) ]
return [ route.host for route in routes.filter(pk__in=pks) ]
def get_backend(self):
for backend in ServiceBackend.get_backends():
if backend.get_name() == self.backend:
return backend
raise KeyError('This backend is not registered')
# def get_method_class(self):
# for method in MethodBackend.get_backends():
# if method.get_name() == self.method:
# return method
# raise ValueError('This method is not registered')
def enable(self):
self.is_active = True
self.save()
def disable(self):
self.is_active = False
self.save()