180 lines
6.1 KiB
Python
180 lines
6.1 KiB
Python
try:
|
|
import cPickle as pickle
|
|
except ImportError:
|
|
import pickle
|
|
import six
|
|
|
|
import django
|
|
from django import forms
|
|
from django.db import models
|
|
from django.db.models.lookups import Exact, In
|
|
from django.core.exceptions import ValidationError
|
|
from django.utils.text import capfirst
|
|
from django.contrib.humanize.templatetags.humanize \
|
|
import apnumber
|
|
from django.template.defaultfilters import pluralize
|
|
|
|
# This is a copy of http://djangosnippets.org/snippets/513/
|
|
#
|
|
# A field which can store any pickleable object in the database. It is
|
|
# database-agnostic, and should work with any database backend you can throw at
|
|
# it.
|
|
#
|
|
# Pass in any object and it will be automagically converted behind the scenes,
|
|
# and you never have to manually pickle or unpickle anything. Also works fine
|
|
# when querying.
|
|
#
|
|
# Initial author: Oliver Beattie
|
|
|
|
class PickledObject(str):
|
|
"""A subclass of string so it can be told whether a string is
|
|
a pickled object or not (if the object is an instance of this class
|
|
then it must [well, should] be a pickled one)."""
|
|
pass
|
|
|
|
try:
|
|
# make PickledObject compatible with Postgres
|
|
import psycopg2.extensions
|
|
psycopg2.extensions.register_adapter(PickledObject, psycopg2.extensions.QuotedString)
|
|
except ImportError:
|
|
pass
|
|
|
|
|
|
def do_pickle(value):
|
|
if value is not None and not isinstance(value, PickledObject):
|
|
value = PickledObject(pickle.dumps(value))
|
|
return value
|
|
|
|
|
|
class PickledObjectField(models.Field):
|
|
|
|
def to_python(self, value):
|
|
if isinstance(value, PickledObject):
|
|
# If the value is a definite pickle; and an error is raised in
|
|
# de-pickling it should be allowed to propogate.
|
|
return pickle.loads(str(value))
|
|
else:
|
|
try:
|
|
return pickle.loads(str(value))
|
|
except:
|
|
# If an error was raised, just return the plain value
|
|
return value
|
|
|
|
def from_db_value(self, value, expression, connection, context):
|
|
return self.to_python(value)
|
|
|
|
def get_db_prep_save(self, value, connection):
|
|
return do_pickle(value)
|
|
|
|
def get_internal_type(self):
|
|
return 'TextField'
|
|
|
|
def value_to_string(self, obj):
|
|
return PickledObject(pickle.dumps(obj))
|
|
|
|
|
|
class PickledObjectFieldExact(Exact):
|
|
|
|
def get_db_prep_lookup(self, value, connection):
|
|
value = do_pickle(value)
|
|
return super(PickledObjectFieldExact, self).get_db_prep_lookup(value, connection)
|
|
|
|
|
|
class PickledObjectFieldIn(In):
|
|
|
|
def get_db_prep_lookup(self, value, connection):
|
|
value = [do_pickle(v) for v in value]
|
|
return super(PickledObjectField, self).get_db_prep_lookup(value, connection)
|
|
|
|
|
|
PickledObjectField.register_lookup(PickledObjectFieldExact)
|
|
PickledObjectField.register_lookup(PickledObjectFieldIn)
|
|
|
|
# This is a modified copy of http://djangosnippets.org/snippets/1200/
|
|
#
|
|
# We added a validate method.
|
|
#
|
|
# Usually you want to store multiple choices as a manytomany link to another
|
|
# table. Sometimes however it is useful to store them in the model itself. This
|
|
# field implements a model field and an accompanying formfield to store multiple
|
|
# choices as a comma-separated list of values, using the normal CHOICES
|
|
# attribute.
|
|
#
|
|
# You'll need to set maxlength long enough to cope with the maximum number of
|
|
# choices, plus a comma for each.
|
|
#
|
|
# The normal get_FOO_display() method returns a comma-delimited string of the
|
|
# expanded values of the selected choices.
|
|
#
|
|
# The formfield takes an optional max_choices parameter to validate a maximum
|
|
# number of choices.
|
|
#
|
|
# Initial author: Daniel Roseman
|
|
|
|
class MultiSelectFormField(forms.MultipleChoiceField):
|
|
widget = forms.CheckboxSelectMultiple
|
|
|
|
def __init__(self, *args, **kwargs):
|
|
self.max_choices = kwargs.pop('max_choices', 0)
|
|
super(MultiSelectFormField, self).__init__(*args, **kwargs)
|
|
|
|
def clean(self, value):
|
|
if not value and self.required:
|
|
raise forms.ValidationError(self.error_messages['required'])
|
|
if value and self.max_choices and len(value) > self.max_choices:
|
|
raise forms.ValidationError('You must select a maximum of %s choice%s.'
|
|
% (apnumber(self.max_choices), pluralize(self.max_choices)))
|
|
return value
|
|
|
|
class MultiSelectField(models.Field):
|
|
|
|
def get_internal_type(self):
|
|
return "CharField"
|
|
|
|
def get_choices_default(self):
|
|
return self.get_choices(include_blank=False)
|
|
|
|
def _get_FIELD_display(self, field):
|
|
pass
|
|
|
|
def formfield(self, **kwargs):
|
|
# don't call super, as that overrides default widget if it has choices
|
|
defaults = {'required': not self.blank, 'label': capfirst(self.verbose_name),
|
|
'help_text': self.help_text, 'choices':self.choices}
|
|
if self.has_default():
|
|
defaults['initial'] = self.get_default()
|
|
defaults.update(kwargs)
|
|
return MultiSelectFormField(**defaults)
|
|
|
|
def get_db_prep_value(self, value, connection, prepared=False):
|
|
if isinstance(value, six.string_types):
|
|
return value
|
|
elif isinstance(value, list):
|
|
return ",".join(value)
|
|
|
|
def validate(self, value, model_instance):
|
|
out = set()
|
|
if self.choices:
|
|
out |= set([option_key for option_key,_ in self.choices])
|
|
out = set(value)-out
|
|
if out:
|
|
raise ValidationError(self.error_messages['invalid_choice'] % ','.join(list(out)))
|
|
if not value and not self.blank:
|
|
raise ValidationError(self.error_messages['blank'])
|
|
|
|
def to_python(self, value):
|
|
if isinstance(value, list):
|
|
return value
|
|
if not value:
|
|
return []
|
|
return value.split(",")
|
|
|
|
def from_db_value(self, value, expression, connection, context):
|
|
return self.to_python(value)
|
|
|
|
def contribute_to_class(self, cls, name):
|
|
super(MultiSelectField, self).contribute_to_class(cls, name)
|
|
if self.choices:
|
|
func = lambda self, fieldname = name, choicedict = dict(self.choices):",".join([choicedict.get(value,value) for value in getattr(self,fieldname)])
|
|
setattr(cls, 'get_%s_display' % self.name, func)
|