forms.py

   1 from django.core.exceptions import ValidationError
   2 from django.forms.models import model_to_dict, fields_for_model, ModelFormMetaclass, ModelForm
   3 from django.template import loader, loader_tags, TemplateDoesNotExist, Context, Template as DjangoTemplate
   4 from django.utils.datastructures import SortedDict
   5 from philo.models import Entity, Template
   6 from philo.models.fields import RelationshipField
   7 from philo.utils import fattr
   8
   9
  10 __all__ = ('EntityForm', )
  11
  12
  13 def proxy_fields_for_entity_model(entity_model, fields=None, exclude=None, widgets=None, formfield_callback=lambda f, **kwargs: f.formfield(**kwargs)):
  14         field_list = []
  15         ignored = []
  16         opts = entity_model._entity_meta
  17         for f in opts.proxy_fields:
  18                 if fields and not f.name in fields:
  19                         continue
  20                 if exclude and f.name in exclude:
  21                         continue
  22                 if widgets and f.name in widgets:
  23                         kwargs = {'widget': widgets[f.name]}
  24                 else:
  25                         kwargs = {}
  26                 formfield = formfield_callback(f, **kwargs)
  27                 if formfield:
  28                         field_list.append((f.name, formfield))
  29                 else:
  30                         ignored.append(f.name)
  31         field_dict = SortedDict(field_list)
  32         if fields:
  33                 field_dict = SortedDict(
  34                         [(f, field_dict.get(f)) for f in fields
  35                                 if ((not exclude) or (exclude and f not in exclude)) and (f not in ignored) and (f in field_dict)]
  36                 )
  37         return field_dict
  38
  39
  40 # BEGIN HACK - This will not be required after http://code.djangoproject.com/ticket/14082 has been resolved
  41
  42 class EntityFormBase(ModelForm):
  43         pass
  44
  45 _old_metaclass_new = ModelFormMetaclass.__new__
  46
  47 def _new_metaclass_new(cls, name, bases, attrs):
  48         new_class = _old_metaclass_new(cls, name, bases, attrs)
  49         if issubclass(new_class, EntityFormBase) and new_class._meta.model:
  50                 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
  51         return new_class
  52
  53 ModelFormMetaclass.__new__ = staticmethod(_new_metaclass_new)
  54
  55 # END HACK
  56
  57
  58 class EntityForm(EntityFormBase): # Would inherit from ModelForm directly if it weren't for the above HACK
  59         def __init__(self, *args, **kwargs):
  60                 initial = kwargs.pop('initial', None)
  61                 instance = kwargs.get('instance', None)
  62                 if instance is not None:
  63                         new_initial = {}
  64                         for f in instance._entity_meta.proxy_fields:
  65                                 if self._meta.fields and not f.name in self._meta.fields:
  66                                         continue
  67                                 if self._meta.exclude and f.name in self._meta.exclude:
  68                                         continue
  69                                 new_initial[f.name] = f.value_from_object(instance)
  70                 else:
  71                         new_initial = {}
  72                 if initial is not None:
  73                         new_initial.update(initial)
  74                 kwargs['initial'] = new_initial
  75                 super(EntityForm, self).__init__(*args, **kwargs)
  76
  77         @fattr(alters_data=True)
  78         def save(self, commit=True):
  79                 cleaned_data = self.cleaned_data
  80                 instance = super(EntityForm, self).save(commit=False)
  81
  82                 for f in instance._entity_meta.proxy_fields:
  83                         if self._meta.fields and f.name not in self._meta.fields:
  84                                 continue
  85                         setattr(instance, f.attname, cleaned_data[f.name])
  86
  87                 if commit:
  88                         instance.save()
  89                         self.save_m2m()
  90
  91                 return instance
  92
  93
  94 def validate_template(template):
  95         """
  96         Makes sure that the template and all included or extended templates are valid.
  97         """
  98         for node in template.nodelist:
  99                 try:
 100                         if isinstance(node, loader_tags.ExtendsNode):
 101                                 extended_template = node.get_parent(Context())
 102                                 validate_template(extended_template)
 103                         elif isinstance(node, loader_tags.IncludeNode):
 104                                 included_template = loader.get_template(node.template_name.resolve(Context()))
 105                                 validate_template(extended_template)
 106                 except Exception, e:
 107                         raise ValidationError("Template code invalid. Error was: %s: %s" % (e.__class__.__name__, e))
 108
 109
 110 class TemplateForm(ModelForm):
 111         def clean_code(self):
 112                 code = self.cleaned_data['code']
 113                 try:
 114                         t = DjangoTemplate(code)
 115                 except Exception, e:
 116                         raise ValidationError("Template code invalid. Error was: %s: %s" % (e.__class__.__name__, e))
 117
 118                 validate_template(t)
 119                 return code
 120
 121         class Meta:
 122                 model = Template