blob: 360792f610b9397d2dc5c546c7416ba271d4ecde [file] [log] [blame]
import datetime
import os
import sys
from django import db
from django.db import models
from django.forms.models import model_to_dict
from django.core.urlresolvers import reverse
from django.forms.models import model_to_dict
from django.utils import timezone
from django.core.exceptions import PermissionDenied
import model_policy
from model_autodeletion import ephemeral_models
from cgi import escape as html_escape
try:
# This is a no-op if observer_disabled is set to 1 in the config file
from observer import *
except:
print >> sys.stderr, "import of observer failed! printing traceback and disabling observer:"
import traceback
traceback.print_exc()
# guard against something failing
def notify_observer(*args, **kwargs):
pass
class StrippedCharField(models.CharField):
""" CharField that strips trailing and leading spaces."""
def clean(self, value, *args, **kwds):
if value is not None:
value = value.strip()
return super(StrippedCharField, self).clean(value, *args, **kwds)
# This manager will be inherited by all subclasses because
# the core model is abstract.
class PlCoreBaseDeletionManager(models.Manager):
def get_queryset(self):
parent=super(PlCoreBaseDeletionManager, self)
if hasattr(parent, "get_queryset"):
return parent.get_queryset().filter(deleted=True)
else:
return parent.get_query_set().filter(deleted=True)
# deprecated in django 1.7 in favor of get_queryset().
def get_query_set(self):
return self.get_queryset()
# This manager will be inherited by all subclasses because
# the core model is abstract.
class PlCoreBaseManager(models.Manager):
def get_queryset(self):
parent=super(PlCoreBaseManager, self)
if hasattr(parent, "get_queryset"):
return parent.get_queryset().filter(deleted=False)
else:
return parent.get_query_set().filter(deleted=False)
# deprecated in django 1.7 in favor of get_queryset().
def get_query_set(self):
return self.get_queryset()
class PlModelMixIn(object):
# Provides useful methods for computing which objects in a model have
# changed. Make sure to do self._initial = self._dict in the __init__
# method.
# Also includes useful utility, like getValidators
# This is broken out of PlCoreBase into a Mixin so the User model can
# also make use of it.
@property
def _dict(self):
return model_to_dict(self, fields=[field.name for field in
self._meta.fields])
def fields_differ(self,f1,f2):
if isinstance(f1,datetime.datetime) and isinstance(f2,datetime.datetime) and (timezone.is_aware(f1) != timezone.is_aware(f2)):
return True
else:
return (f1 != f2)
@property
def diff(self):
d1 = self._initial
d2 = self._dict
diffs = [(k, (v, d2[k])) for k, v in d1.items() if self.fields_differ(v,d2[k])]
return dict(diffs)
@property
def has_changed(self):
return bool(self.diff)
@property
def changed_fields(self):
return self.diff.keys()
def has_field_changed(self, field_name):
return field_name in self.diff.keys()
def get_field_diff(self, field_name):
return self.diff.get(field_name, None)
#classmethod
def getValidators(cls):
""" primarily for REST API, return a dictionary of field names mapped
to lists of the type of validations that need to be applied to
those fields.
"""
validators = {}
for field in cls._meta.fields:
l = []
if field.blank==False:
l.append("notBlank")
if field.__class__.__name__=="URLField":
l.append("url")
validators[field.name] = l
return validators
def get_backend_icon(self):
is_perfect = (self.backend_status is not None) and self.backend_status.startswith("1 -")
is_good = (self.backend_status is not None) and (self.backend_status.startswith("0 -") or self.backend_status.startswith("1 -"))
is_provisioning = self.backend_status is None or self.backend_status == "Provisioning in progress" or self.backend_status==""
# returns (icon_name, tooltip)
if (self.enacted is not None) and (self.enacted >= self.updated and is_good) or is_perfect:
return ("success", "successfully enacted")
else:
if is_good or is_provisioning:
return ("clock", "Pending sync, last_status = " + html_escape(self.backend_status, quote=True))
else:
return ("error", html_escape(self.backend_status, quote=True))
def enforce_choices(self, field, choices):
choices = [x[0] for x in choices]
for choice in choices:
if field==choice:
return
if (choice==None) and (field==""):
# allow "" and None to be equivalent
return
raise Exception("Field value %s is not in %s" % (field, str(choices)))
class PlCoreBase(models.Model, PlModelMixIn):
objects = PlCoreBaseManager()
deleted_objects = PlCoreBaseDeletionManager()
# default values for created and updated are only there to keep evolution
# from failing.
created = models.DateTimeField(auto_now_add=True, default=timezone.now)
updated = models.DateTimeField(auto_now=True, default=timezone.now)
enacted = models.DateTimeField(null=True, blank=True, default=None)
policed = models.DateTimeField(null=True, blank=True, default=None)
# This is a scratchpad used by the Observer
backend_register = models.CharField(max_length=140,
default="{}", null=True)
backend_status = models.CharField(max_length=1024,
default="0 - Provisioning in progress")
deleted = models.BooleanField(default=False)
write_protect = models.BooleanField(default=False)
lazy_blocked = models.BooleanField(default=False)
no_sync = models.BooleanField(default=False)
class Meta:
# Changing abstract to False would require the managers of subclasses of
# PlCoreBase to be customized individually.
abstract = True
app_label = "core"
def __init__(self, *args, **kwargs):
super(PlCoreBase, self).__init__(*args, **kwargs)
self._initial = self._dict # for PlModelMixIn
self.silent = False
def can_update(self, user):
return user.can_update_root()
def delete(self, *args, **kwds):
# so we have something to give the observer
purge = kwds.get('purge',False)
if purge:
del kwds['purge']
silent = kwds.get('silent',False)
if silent:
del kwds['silent']
try:
purge = purge or observer_disabled
except NameError:
pass
if (purge):
super(PlCoreBase, self).delete(*args, **kwds)
else:
if (not self.write_protect):
self.deleted = True
self.enacted=None
self.policed=None
self.save(update_fields=['enacted','deleted','policed'], silent=silent)
def save(self, *args, **kwargs):
# let the user specify silence as either a kwarg or an instance varible
silent = self.silent
if "silent" in kwargs:
silent=silent or kwargs.pop("silent")
# SMBAKER: if an object is trying to delete itself, or if the observer
# is updating an object's backend_* fields, then let it slip past the
# composite key check.
ignore_composite_key_check=False
if "update_fields" in kwargs:
ignore_composite_key_check=True
for field in kwargs["update_fields"]:
if not (field in ["backend_register", "backend_status", "deleted", "enacted", "updated"]):
ignore_composite_key_check=False
super(PlCoreBase, self).save(*args, **kwargs)
# This is a no-op if observer_disabled is set
# if not silent:
# notify_observer()
self._initial = self._dict
def save_by_user(self, user, *args, **kwds):
if not self.can_update(user):
if getattr(self, "_cant_update_fieldName", None) is not None:
raise PermissionDenied("You do not have permission to update field %s on object %s" % (self._cant_update_fieldName, self.__class__.__name__))
else:
raise PermissionDenied("You do not have permission to update %s objects" % self.__class__.__name__)
self.save(*args, **kwds)
def delete_by_user(self, user, *args, **kwds):
if not self.can_update(user):
raise PermissionDenied("You do not have permission to delete %s objects" % self.__class__.__name__)
self.delete(*args, **kwds)
@classmethod
def select_by_user(cls, user):
# This should be overridden by descendant classes that want to perform
# filtering of visible objects by user.
return cls.objects.all()
@classmethod
def is_ephemeral(cls):
return cls in ephemeral_models