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