forms.py

   1 from django import forms
   2 from django.contrib.admin.widgets import AdminTextareaWidget
   3 from django.contrib.contenttypes.generic import BaseGenericInlineFormSet
   4 from django.contrib.contenttypes.models import ContentType
   5 from django.core.exceptions import ValidationError, ObjectDoesNotExist
   6 from django.db.models import Q
   7 from django.forms.models import model_to_dict, fields_for_model, ModelFormMetaclass, ModelForm, BaseInlineFormSet
   8 from django.forms.formsets import TOTAL_FORM_COUNT
   9 from django.template import loader, loader_tags, TemplateDoesNotExist, Context, Template as DjangoTemplate
  10 from django.utils.datastructures import SortedDict
  11 from philo.admin.widgets import ModelLookupWidget
  12 from philo.models import Entity, Template, Contentlet, ContentReference, Attribute
  13 from philo.utils import fattr
  14
  15
  16 __all__ = ('EntityForm', )
  17
  18
  19 def proxy_fields_for_entity_model(entity_model, fields=None, exclude=None, widgets=None, formfield_callback=lambda f, **kwargs: f.formfield(**kwargs)):
  20         field_list = []
  21         ignored = []
  22         opts = entity_model._entity_meta
  23         for f in opts.proxy_fields:
  24                 if fields and not f.name in fields:
  25                         continue
  26                 if exclude and f.name in exclude:
  27                         continue
  28                 if widgets and f.name in widgets:
  29                         kwargs = {'widget': widgets[f.name]}
  30                 else:
  31                         kwargs = {}
  32                 formfield = formfield_callback(f, **kwargs)
  33                 if formfield:
  34                         field_list.append((f.name, formfield))
  35                 else:
  36                         ignored.append(f.name)
  37         field_dict = SortedDict(field_list)
  38         if fields:
  39                 field_dict = SortedDict(
  40                         [(f, field_dict.get(f)) for f in fields
  41                                 if ((not exclude) or (exclude and f not in exclude)) and (f not in ignored) and (f in field_dict)]
  42                 )
  43         return field_dict
  44
  45
  46 # BEGIN HACK - This will not be required after http://code.djangoproject.com/ticket/14082 has been resolved
  47
  48 class EntityFormBase(ModelForm):
  49         pass
  50
  51 _old_metaclass_new = ModelFormMetaclass.__new__
  52
  53 def _new_metaclass_new(cls, name, bases, attrs):
  54         new_class = _old_metaclass_new(cls, name, bases, attrs)
  55         if issubclass(new_class, EntityFormBase) and new_class._meta.model:
  56                 new_class.base_fields.update(proxy_fields_for_entity_model(new_class._meta.model, new_class._meta.fields, new_class._meta.exclude, new_class._meta.widgets)) # don't pass in formfield_callback
  57         return new_class
  58
  59 ModelFormMetaclass.__new__ = staticmethod(_new_metaclass_new)
  60
  61 # END HACK
  62
  63
  64 class EntityForm(EntityFormBase): # Would inherit from ModelForm directly if it weren't for the above HACK
  65         def __init__(self, *args, **kwargs):
  66                 initial = kwargs.pop('initial', None)
  67                 instance = kwargs.get('instance', None)
  68                 if instance is not None:
  69                         new_initial = {}
  70                         for f in instance._entity_meta.proxy_fields:
  71                                 if self._meta.fields and not f.name in self._meta.fields:
  72                                         continue
  73                                 if self._meta.exclude and f.name in self._meta.exclude:
  74                                         continue
  75                                 new_initial[f.name] = f.value_from_object(instance)
  76                 else:
  77                         new_initial = {}
  78                 if initial is not None:
  79                         new_initial.update(initial)
  80                 kwargs['initial'] = new_initial
  81                 super(EntityForm, self).__init__(*args, **kwargs)
  82
  83         @fattr(alters_data=True)
  84         def save(self, commit=True):
  85                 cleaned_data = self.cleaned_data
  86                 instance = super(EntityForm, self).save(commit=False)
  87
  88                 for f in instance._entity_meta.proxy_fields:
  89                         if self._meta.fields and f.name not in self._meta.fields:
  90                                 continue
  91                         setattr(instance, f.attname, cleaned_data[f.name])
  92
  93                 if commit:
  94                         instance.save()
  95                         self.save_m2m()
  96
  97                 return instance
  98
  99
 100 class AttributeForm(ModelForm):
 101         def __init__(self, *args, **kwargs):
 102                 super(AttributeForm, self).__init__(*args, **kwargs)
 103
 104                 # This is necessary because model forms store changes to self.instance in their clean method.
 105                 # Mutter mutter.
 106                 self._cached_value_ct = self.instance.value_content_type
 107                 self._cached_value = self.instance.value
 108
 109                 if self.instance.value is not None:
 110                         value_field = self.instance.value.value_formfield()
 111                         if value_field:
 112                                 self.fields['value'] = value_field
 113                         if hasattr(self.instance.value, 'content_type'):
 114                                 self.fields['content_type'] = self.instance.value._meta.get_field('content_type').formfield(initial=getattr(self.instance.value.content_type, 'pk', None))
 115
 116         def save(self, *args, **kwargs):
 117                 # At this point, the cleaned_data has already been stored on self.instance.
 118                 if self.instance.value_content_type != self._cached_value_ct:
 119                         if self.instance.value is not None:
 120                                 self._cached_value.delete()
 121                                 if 'value' in self.cleaned_data:
 122                                         del(self.cleaned_data['value'])
 123
 124                         if self.instance.value_content_type is not None:
 125                                 # Make a blank value of the new type! Run special code for content_type attributes.
 126                                 if hasattr(self.instance.value_content_type.model_class(), 'content_type'):
 127                                         if self._cached_value and hasattr(self._cached_value, 'content_type'):
 128                                                 new_ct = self._cached_value.content_type
 129                                         else:
 130                                                 new_ct = None
 131                                         new_value = self.instance.value_content_type.model_class().objects.create(content_type=new_ct)
 132                                 else:
 133                                         new_value = self.instance.value_content_type.model_class().objects.create()
 134
 135                                 new_value.apply_data(self.cleaned_data)
 136                                 new_value.save()
 137                                 self.instance.value = new_value
 138                 else:
 139                         # The value type is the same, but one of the fields has changed.
 140                         # Check to see if the changed value was the content type. We have to check the
 141                         # cleaned_data because self.instance.value.content_type was overridden.
 142                         if hasattr(self.instance.value, 'content_type') and 'content_type' in self.cleaned_data and 'value' in self.cleaned_data and (not hasattr(self._cached_value, 'content_type') or self._cached_value.content_type != self.cleaned_data['content_type']):
 143                                 self.cleaned_data['value'] = None
 144
 145                         self.instance.value.apply_data(self.cleaned_data)
 146                         self.instance.value.save()
 147
 148                 super(AttributeForm, self).save(*args, **kwargs)
 149                 return self.instance
 150
 151         class Meta:
 152                 model = Attribute
 153
 154
 155 class AttributeInlineFormSet(BaseGenericInlineFormSet):
 156         "Necessary to force the GenericInlineFormset to use the form's save method for new objects."
 157         def save_new(self, form, commit):
 158                 setattr(form.instance, self.ct_field.get_attname(), ContentType.objects.get_for_model(self.instance).pk)
 159                 setattr(form.instance, self.ct_fk_field.get_attname(), self.instance.pk)
 160                 return form.save()
 161
 162
 163 class ContainerForm(ModelForm):
 164         def __init__(self, *args, **kwargs):
 165                 super(ContainerForm, self).__init__(*args, **kwargs)
 166                 self.verbose_name = self.instance.name.replace('_', ' ')
 167
 168
 169 class ContentletForm(ContainerForm):
 170         content = forms.CharField(required=False, widget=AdminTextareaWidget, label='Content')
 171
 172         def should_delete(self):
 173                 return not bool(self.cleaned_data['content'])
 174
 175         class Meta:
 176                 model = Contentlet
 177                 fields = ['name', 'content']
 178
 179
 180 class ContentReferenceForm(ContainerForm):
 181         def __init__(self, *args, **kwargs):
 182                 super(ContentReferenceForm, self).__init__(*args, **kwargs)
 183                 try:
 184                         self.fields['content_id'].widget = ModelLookupWidget(self.instance.content_type)
 185                 except ObjectDoesNotExist:
 186                         # This will happen when an empty form (which we will never use) gets instantiated.
 187                         pass
 188
 189         def should_delete(self):
 190                 return (self.cleaned_data['content_id'] is None)
 191
 192         class Meta:
 193                 model = ContentReference
 194                 fields = ['name', 'content_id']
 195
 196
 197 class ContainerInlineFormSet(BaseInlineFormSet):
 198         def __init__(self, containers, data=None, files=None, instance=None, save_as_new=False, prefix=None, queryset=None):
 199                 # Unfortunately, I need to add some things to BaseInline between its __init__ and its
 200                 # super call, so a lot of this is repetition.
 201
 202                 # Start cribbed from BaseInline
 203                 from django.db.models.fields.related import RelatedObject
 204                 self.save_as_new = save_as_new
 205                 # is there a better way to get the object descriptor?
 206                 self.rel_name = RelatedObject(self.fk.rel.to, self.model, self.fk).get_accessor_name()
 207                 if self.fk.rel.field_name == self.fk.rel.to._meta.pk.name:
 208                         backlink_value = self.instance
 209                 else:
 210                         backlink_value = getattr(self.instance, self.fk.rel.field_name)
 211                 if queryset is None:
 212                         queryset = self.model._default_manager
 213                 qs = queryset.filter(**{self.fk.name: backlink_value})
 214                 # End cribbed from BaseInline
 215
 216                 self.container_instances, qs = self.get_container_instances(containers, qs)
 217                 self.extra_containers = containers
 218                 self.extra = len(self.extra_containers)
 219                 super(BaseInlineFormSet, self).__init__(data, files, prefix=prefix, queryset=qs)
 220
 221         def get_container_instances(self, containers, qs):
 222                 raise NotImplementedError
 223
 224         def total_form_count(self):
 225                 if self.data or self.files:
 226                         return self.management_form.cleaned_data[TOTAL_FORM_COUNT]
 227                 else:
 228                         return self.initial_form_count() + self.extra
 229
 230         def save_existing_objects(self, commit=True):
 231                 self.changed_objects = []
 232                 self.deleted_objects = []
 233                 if not self.get_queryset():
 234                         return []
 235
 236                 saved_instances = []
 237                 for form in self.initial_forms:
 238                         pk_name = self._pk_field.name
 239                         raw_pk_value = form._raw_value(pk_name)
 240
 241                         # clean() for different types of PK fields can sometimes return
 242                         # the model instance, and sometimes the PK. Handle either.
 243                         pk_value = form.fields[pk_name].clean(raw_pk_value)
 244                         pk_value = getattr(pk_value, 'pk', pk_value)
 245
 246                         obj = self._existing_object(pk_value)
 247                         if form.should_delete():
 248                                 self.deleted_objects.append(obj)
 249                                 obj.delete()
 250                                 continue
 251                         if form.has_changed():
 252                                 self.changed_objects.append((obj, form.changed_data))
 253                                 saved_instances.append(self.save_existing(form, obj, commit=commit))
 254                                 if not commit:
 255                                         self.saved_forms.append(form)
 256                 return saved_instances
 257
 258         def save_new_objects(self, commit=True):
 259                 self.new_objects = []
 260                 for form in self.extra_forms:
 261                         if not form.has_changed():
 262                                 continue
 263                         # If someone has marked an add form for deletion, don't save the
 264                         # object.
 265                         if form.should_delete():
 266                                 continue
 267                         self.new_objects.append(self.save_new(form, commit=commit))
 268                         if not commit:
 269                                 self.saved_forms.append(form)
 270                 return self.new_objects
 271
 272
 273 class ContentletInlineFormSet(ContainerInlineFormSet):
 274         def __init__(self, data=None, files=None, instance=None, save_as_new=False, prefix=None, queryset=None):
 275                 if instance is None:
 276                         self.instance = self.fk.rel.to()
 277                 else:
 278                         self.instance = instance
 279
 280                 try:
 281                         containers = list(self.instance.containers[0])
 282                 except ObjectDoesNotExist:
 283                         containers = []
 284
 285                 super(ContentletInlineFormSet, self).__init__(containers, data, files, instance, save_as_new, prefix, queryset)
 286
 287         def get_container_instances(self, containers, qs):
 288                 qs = qs.filter(name__in=containers)
 289                 container_instances = []
 290                 for container in qs:
 291                         container_instances.append(container)
 292                         containers.remove(container.name)
 293                 return container_instances, qs
 294
 295         def _construct_form(self, i, **kwargs):
 296                 if i >= self.initial_form_count(): # and not kwargs.get('instance'):
 297                         kwargs['instance'] = self.model(name=self.extra_containers[i - self.initial_form_count() - 1])
 298
 299                 return super(ContentletInlineFormSet, self)._construct_form(i, **kwargs)
 300
 301
 302 class ContentReferenceInlineFormSet(ContainerInlineFormSet):
 303         def __init__(self, data=None, files=None, instance=None, save_as_new=False, prefix=None, queryset=None):
 304                 if instance is None:
 305                         self.instance = self.fk.rel.to()
 306                 else:
 307                         self.instance = instance
 308
 309                 try:
 310                         containers = list(self.instance.containers[1])
 311                 except ObjectDoesNotExist:
 312                         containers = []
 313
 314                 super(ContentReferenceInlineFormSet, self).__init__(containers, data, files, instance, save_as_new, prefix, queryset)
 315
 316         def get_container_instances(self, containers, qs):
 317                 filter = Q()
 318
 319                 for name, ct in containers:
 320                         filter |= Q(name=name, content_type=ct)
 321
 322                 qs = qs.filter(filter)
 323                 container_instances = []
 324                 for container in qs:
 325                         container_instances.append(container)
 326                         containers.remove((container.name, container.content_type))
 327                 return container_instances, qs
 328
 329         def _construct_form(self, i, **kwargs):
 330                 if i >= self.initial_form_count(): # and not kwargs.get('instance'):
 331                         name, content_type = self.extra_containers[i - self.initial_form_count() - 1]
 332                         kwargs['instance'] = self.model(name=name, content_type=content_type)
 333
 334                 return super(ContentReferenceInlineFormSet, self)._construct_form(i, **kwargs)