From ae53fdff9c6bb3e81a1ec005134462f0d629688f Mon Sep 17 00:00:00 2001 From: Tom Christie Date: Wed, 22 Oct 2014 13:30:28 +0100 Subject: First pass at unique_for_date, unique_for_month, unique_for_year --- rest_framework/validators.py | 121 +++++++++++++++++++++++++++++++++++-------- 1 file changed, 99 insertions(+), 22 deletions(-) (limited to 'rest_framework/validators.py') diff --git a/rest_framework/validators.py b/rest_framework/validators.py index f76faaa4..e302a0e4 100644 --- a/rest_framework/validators.py +++ b/rest_framework/validators.py @@ -6,38 +6,36 @@ This gives us better separation of concerns, allows us to use single-step object creation, and makes it possible to switch between using the implicit `ModelSerializer` class and an equivelent explicit `Serializer` class. """ -from django.core.exceptions import ValidationError from django.utils.translation import ugettext_lazy as _ +from rest_framework.exceptions import ValidationError from rest_framework.utils.representation import smart_repr class UniqueValidator: """ Validator that corresponds to `unique=True` on a model field. + + Should be applied to an individual field on the serializer. """ - # Validators with `requires_context` will have the field instance - # passed to them when the field is instantiated. - requires_context = True message = _('This field must be unique.') def __init__(self, queryset): self.queryset = queryset self.serializer_field = None - def __call__(self, value): - field = self.serializer_field - - # Determine the model field name that the serializer field corresponds to. - field_name = field.source_attrs[0] if field.source_attrs else field.field_name - + def set_context(self, serializer_field): + # Determine the underlying model field name. This may not be the + # same as the serializer field name if `source=<>` is set. + self.field_name = serializer_field.source_attrs[0] # Determine the existing instance, if this is an update operation. - instance = getattr(field.parent, 'instance', None) + self.instance = getattr(serializer_field.parent, 'instance', None) + def __call__(self, value): # Ensure uniqueness. - filter_kwargs = {field_name: value} + filter_kwargs = {self.field_name: value} queryset = self.queryset.filter(**filter_kwargs) - if instance: - queryset = queryset.exclude(pk=instance.pk) + if self.instance is not None: + queryset = queryset.exclude(pk=self.instance.pk) if queryset.exists(): raise ValidationError(self.message) @@ -51,8 +49,9 @@ class UniqueValidator: class UniqueTogetherValidator: """ Validator that corresponds to `unique_together = (...)` on a model class. + + Should be applied to the serializer class, not to an individual field. """ - requires_context = True message = _('The fields {field_names} must make a unique set.') def __init__(self, queryset, fields): @@ -60,19 +59,18 @@ class UniqueTogetherValidator: self.fields = fields self.serializer_field = None - def __call__(self, value): - serializer = self.serializer_field - + def set_context(self, serializer): # Determine the existing instance, if this is an update operation. - instance = getattr(serializer, 'instance', None) + self.instance = getattr(serializer, 'instance', None) + def __call__(self, attrs): # Ensure uniqueness. filter_kwargs = dict([ - (field_name, value[field_name]) for field_name in self.fields + (field_name, attrs[field_name]) for field_name in self.fields ]) queryset = self.queryset.filter(**filter_kwargs) - if instance: - queryset = queryset.exclude(pk=instance.pk) + if self.instance is not None: + queryset = queryset.exclude(pk=self.instance.pk) if queryset.exists(): field_names = ', '.join(self.fields) raise ValidationError(self.message.format(field_names=field_names)) @@ -83,3 +81,82 @@ class UniqueTogetherValidator: smart_repr(self.queryset), smart_repr(self.fields) ) + + +class BaseUniqueForValidator: + message = None + + def __init__(self, queryset, field, date_field): + self.queryset = queryset + self.field = field + self.date_field = date_field + + def set_context(self, serializer): + # Determine the underlying model field names. These may not be the + # same as the serializer field names if `source=<>` is set. + self.field_name = serializer.fields[self.field].source_attrs[0] + self.date_field_name = serializer.fields[self.date_field].source_attrs[0] + # Determine the existing instance, if this is an update operation. + self.instance = getattr(serializer, 'instance', None) + + def get_filter_kwargs(self, attrs): + raise NotImplementedError('`get_filter_kwargs` must be implemented.') + + def __call__(self, attrs): + filter_kwargs = self.get_filter_kwargs(attrs) + + queryset = self.queryset.filter(**filter_kwargs) + if self.instance is not None: + queryset = queryset.exclude(pk=self.instance.pk) + if queryset.exists(): + message = self.message.format(date_field=self.date_field) + raise ValidationError({self.field: message}) + + def __repr__(self): + return '<%s(queryset=%s, field=%s, date_field=%s)>' % ( + self.__class__.__name__, + smart_repr(self.queryset), + smart_repr(self.field), + smart_repr(self.date_field) + ) + + +class UniqueForDateValidator(BaseUniqueForValidator): + message = _('This field must be unique for the "{date_field}" date.') + + def get_filter_kwargs(self, attrs): + value = attrs[self.field] + date = attrs[self.date_field] + + filter_kwargs = {} + filter_kwargs[self.field_name] = value + filter_kwargs['%s__day' % self.date_field_name] = date.day + filter_kwargs['%s__month' % self.date_field_name] = date.month + filter_kwargs['%s__year' % self.date_field_name] = date.year + return filter_kwargs + + +class UniqueForMonthValidator(BaseUniqueForValidator): + message = _('This field must be unique for the "{date_field}" month.') + + def get_filter_kwargs(self, attrs): + value = attrs[self.field] + date = attrs[self.date_field] + + filter_kwargs = {} + filter_kwargs[self.field_name] = value + filter_kwargs['%s__month' % self.date_field_name] = date.month + return filter_kwargs + + +class UniqueForYearValidator(BaseUniqueForValidator): + message = _('This field must be unique for the "{date_field}" year.') + + def get_filter_kwargs(self, attrs): + value = attrs[self.field] + date = attrs[self.date_field] + + filter_kwargs = {} + filter_kwargs[self.field_name] = value + filter_kwargs['%s__year' % self.date_field_name] = date.year + return filter_kwargs -- cgit v1.2.3