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First non-tested version of moving typeclasses to proxy models.

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Griatch 2014-12-19 16:29:41 +01:00
parent 8e8d85a4fe
commit 236c0d17d3
9 changed files with 403 additions and 622 deletions
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275
src/utils/idmapper/base.py
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@ -22,6 +22,21 @@ from manager import SharedMemoryManager
AUTO_FLUSH_MIN_INTERVAL = 60.0 * 5 # at least 5 mins between cache flushes
# django patch imports
import copy
import sys
from django.apps import apps
from django.db.models.base import subclass_exception
import warnings
from django.db.models.options import Options
from django.utils.deprecation import RemovedInDjango19Warning
from django.core.exceptions import (ObjectDoesNotExist,
MultipleObjectsReturned, FieldError)
from django.apps.config import MODELS_MODULE_NAME
from django.db.models.fields.related import OneToOneField
#/ django patch imports
_GA = object.__getattribute__
_SA = object.__setattr__
_DA = object.__delattr__
@ -72,7 +87,7 @@ class SharedMemoryModelBase(ModelBase):
cls._idmapper_recache_protection = False
super(SharedMemoryModelBase, cls)._prepare()
def __new__(cls, classname, bases, classdict, *args, **kwargs):
def __new__(cls, name, bases, attrs):
"""
Field shortcut creation:
Takes field names db_* and creates property wrappers named without the db_ prefix. So db_key -> key
@ -158,23 +173,273 @@ class SharedMemoryModelBase(ModelBase):
fset = lambda cls, val: _set(cls, fieldname, val)
fdel = lambda cls: _del(cls, fieldname) if editable else _del_nonedit(cls,fieldname)
# assigning
classdict[wrappername] = property(fget, fset, fdel)
attrs[wrappername] = property(fget, fset, fdel)
#type(cls).__setattr__(cls, wrappername, property(fget, fset, fdel))#, doc))
# exclude some models that should not auto-create wrapper fields
if cls.__name__ in ("ServerConfig", "TypeNick"):
return
# dynamically create the wrapper properties for all fields not already handled (manytomanyfields are always handlers)
for fieldname, field in ((fname, field) for fname, field in classdict.items()
for fieldname, field in ((fname, field) for fname, field in attrs.items()
if fname.startswith("db_") and type(field).__name__ != "ManyToManyField"):
foreignkey = type(field).__name__ == "ForeignKey"
#print fieldname, type(field).__name__, field
wrappername = "dbid" if fieldname == "id" else fieldname.replace("db_", "", 1)
if wrappername not in classdict:
if wrappername not in attrs:
# makes sure not to overload manually created wrappers on the model
#print "wrapping %s -> %s" % (fieldname, wrappername)
create_wrapper(cls, fieldname, wrappername, editable=field.editable, foreignkey=foreignkey)
return super(SharedMemoryModelBase, cls).__new__(cls, classname, bases, classdict, *args, **kwargs)
# django patch
# Evennia mod, based on Django Ticket #11560: https://code.djangoproject.com/ticket/11560
# The actual patch is small and further down.
super_new = super(ModelBase, cls).__new__
# Also ensure initialization is only performed for subclasses of Model
# (excluding Model class itself).
parents = [b for b in bases if isinstance(b, ModelBase)]
if not parents:
return super_new(cls, name, bases, attrs)
# Create the class.
module = attrs.pop('__module__')
new_class = super_new(cls, name, bases, {'__module__': module})
attr_meta = attrs.pop('Meta', None)
abstract = getattr(attr_meta, 'abstract', False)
if not attr_meta:
meta = getattr(new_class, 'Meta', None)
else:
meta = attr_meta
base_meta = getattr(new_class, '_meta', None)
# Look for an application configuration to attach the model to.
app_config = apps.get_containing_app_config(module)
if getattr(meta, 'app_label', None) is None:
if app_config is None:
# If the model is imported before the configuration for its
# application is created (#21719), or isn't in an installed
# application (#21680), use the legacy logic to figure out the
# app_label by looking one level up from the package or module
# named 'models'. If no such package or module exists, fall
# back to looking one level up from the module this model is
# defined in.
# For 'django.contrib.sites.models', this would be 'sites'.
# For 'geo.models.places' this would be 'geo'.
msg = (
"Model class %s.%s doesn't declare an explicit app_label "
"and either isn't in an application in INSTALLED_APPS or "
"else was imported before its application was loaded. " %
(module, name))
if abstract:
msg += "Its app_label will be set to None in Django 1.9."
else:
msg += "This will no longer be supported in Django 1.9."
warnings.warn(msg, RemovedInDjango19Warning, stacklevel=2)
model_module = sys.modules[new_class.__module__]
package_components = model_module.__name__.split('.')
package_components.reverse() # find the last occurrence of 'models'
try:
app_label_index = package_components.index(MODELS_MODULE_NAME) + 1
except ValueError:
app_label_index = 1
kwargs = {"app_label": package_components[app_label_index]}
else:
kwargs = {"app_label": app_config.label}
else:
kwargs = {}
new_class.add_to_class('_meta', Options(meta, **kwargs))
if not abstract:
new_class.add_to_class(
'DoesNotExist',
subclass_exception(
str('DoesNotExist'),
tuple(x.DoesNotExist for x in parents if hasattr(x, '_meta') and not x._meta.abstract) or (ObjectDoesNotExist,),
module,
attached_to=new_class))
new_class.add_to_class(
'MultipleObjectsReturned',
subclass_exception(
str('MultipleObjectsReturned'),
tuple(x.MultipleObjectsReturned for x in parents if hasattr(x, '_meta') and not x._meta.abstract) or (MultipleObjectsReturned,),
module,
attached_to=new_class))
if base_meta and not base_meta.abstract:
# Non-abstract child classes inherit some attributes from their
# non-abstract parent (unless an ABC comes before it in the
# method resolution order).
if not hasattr(meta, 'ordering'):
new_class._meta.ordering = base_meta.ordering
if not hasattr(meta, 'get_latest_by'):
new_class._meta.get_latest_by = base_meta.get_latest_by
is_proxy = new_class._meta.proxy
# If the model is a proxy, ensure that the base class
# hasn't been swapped out.
if is_proxy and base_meta and base_meta.swapped:
raise TypeError("%s cannot proxy the swapped model '%s'." % (name, base_meta.swapped))
if getattr(new_class, '_default_manager', None):
if not is_proxy:
# Multi-table inheritance doesn't inherit default manager from
# parents.
new_class._default_manager = None
new_class._base_manager = None
else:
# Proxy classes do inherit parent's default manager, if none is
# set explicitly.
new_class._default_manager = new_class._default_manager._copy_to_model(new_class)
new_class._base_manager = new_class._base_manager._copy_to_model(new_class)
# Add all attributes to the class.
for obj_name, obj in attrs.items():
new_class.add_to_class(obj_name, obj)
# All the fields of any type declared on this model
new_fields = (
new_class._meta.local_fields +
new_class._meta.local_many_to_many +
new_class._meta.virtual_fields
)
field_names = set(f.name for f in new_fields)
# Basic setup for proxy models.
if is_proxy:
base = None
for parent in [kls for kls in parents if hasattr(kls, '_meta')]:
if parent._meta.abstract:
if parent._meta.fields:
raise TypeError("Abstract base class containing model fields not permitted for proxy model '%s'." % name)
else:
continue
# Evennia mod, based on Django Ticket #11560: https://code.djangoproject.com/ticket/11560
# This allows multiple inheritance for proxy models
while parent._meta.proxy:
parent = parent._meta.proxy_for_model
if base is not None and base is not parent:
#if base is not None:
raise TypeError("Proxy model '%s' has more than one non-abstract model base class." % name)
else:
base = parent
if base is None:
raise TypeError("Proxy model '%s' has no non-abstract model base class." % name)
new_class._meta.setup_proxy(base)
new_class._meta.concrete_model = base._meta.concrete_model
else:
new_class._meta.concrete_model = new_class
# Collect the parent links for multi-table inheritance.
parent_links = {}
for base in reversed([new_class] + parents):
# Conceptually equivalent to `if base is Model`.
if not hasattr(base, '_meta'):
continue
# Skip concrete parent classes.
if base != new_class and not base._meta.abstract:
continue
# Locate OneToOneField instances.
for field in base._meta.local_fields:
if isinstance(field, OneToOneField):
parent_links[field.rel.to] = field
# Do the appropriate setup for any model parents.
for base in parents:
original_base = base
if not hasattr(base, '_meta'):
# Things without _meta aren't functional models, so they're
# uninteresting parents.
continue
parent_fields = base._meta.local_fields + base._meta.local_many_to_many
# Check for clashes between locally declared fields and those
# on the base classes (we cannot handle shadowed fields at the
# moment).
for field in parent_fields:
if field.name in field_names:
raise FieldError(
'Local field %r in class %r clashes '
'with field of similar name from '
'base class %r' % (field.name, name, base.__name__)
)
if not base._meta.abstract:
# Concrete classes...
base = base._meta.concrete_model
if base in parent_links:
field = parent_links[base]
elif not is_proxy:
attr_name = '%s_ptr' % base._meta.model_name
field = OneToOneField(base, name=attr_name,
auto_created=True, parent_link=True)
# Only add the ptr field if it's not already present;
# e.g. migrations will already have it specified
if not hasattr(new_class, attr_name):
new_class.add_to_class(attr_name, field)
else:
field = None
new_class._meta.parents[base] = field
else:
# .. and abstract ones.
for field in parent_fields:
new_class.add_to_class(field.name, copy.deepcopy(field))
# Pass any non-abstract parent classes onto child.
new_class._meta.parents.update(base._meta.parents)
# Inherit managers from the abstract base classes.
new_class.copy_managers(base._meta.abstract_managers)
# Proxy models inherit the non-abstract managers from their base,
# unless they have redefined any of them.
if is_proxy:
new_class.copy_managers(original_base._meta.concrete_managers)
# Inherit virtual fields (like GenericForeignKey) from the parent
# class
for field in base._meta.virtual_fields:
if base._meta.abstract and field.name in field_names:
raise FieldError(
'Local field %r in class %r clashes '
'with field of similar name from '
'abstract base class %r' % (field.name, name, base.__name__)
)
new_class.add_to_class(field.name, copy.deepcopy(field))
if abstract:
# Abstract base models can't be instantiated and don't appear in
# the list of models for an app. We do the final setup for them a
# little differently from normal models.
attr_meta.abstract = False
new_class.Meta = attr_meta
return new_class
new_class._prepare()
new_class._meta.apps.register_model(new_class._meta.app_label, new_class)
return new_class
class TypeclassModelBase(SharedMemoryModelBase):
"""
Metaclass for typeclasses
"""
def __init__(cls, *args, **kwargs):
"""
We must define our Typeclasses as proxies. We also store the path
directly on the class, this is useful for managers.
"""
super(TypeclassModelBase, cls).__init__(*args, **kwargs)
class Meta:
proxy = True
cls.Meta = Meta
cls.typename = cls.__name__
cls.path = "%s.%s" % (cls.__module__, cls.__name__)
class SharedMemoryModel(Model):