forms.py

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