# encoding: utf-8
from __future__ import absolute_import, division, print_function, unicode_literals
import re
from django.template import Context, loader
from django.utils import datetime_safe, six
from haystack.exceptions import SearchFieldError
from haystack.utils import get_model_ct_tuple
class NOT_PROVIDED:
pass
# Note that dates in the full ISO 8601 format will be accepted as long as the hour/minute/second components
# are zeroed for compatibility with search backends which lack a date time distinct from datetime:
DATE_REGEX = re.compile(r'^(?P<year>\d{4})-(?P<month>\d{2})-(?P<day>\d{2})(?:|T00:00:00Z?)$')
DATETIME_REGEX = re.compile(r'^(?P<year>\d{4})-(?P<month>\d{2})-(?P<day>\d{2})(T|\s+)(?P<hour>\d{2}):(?P<minute>\d{2}):(?P<second>\d{2}).*?$')
# All the SearchFields variants.
class SearchField(object):
"""The base implementation of a search field."""
field_type = None
def __init__(self, model_attr=None, use_template=False, template_name=None,
document=False, indexed=True, stored=True, faceted=False,
default=NOT_PROVIDED, null=False, index_fieldname=None,
facet_class=None, boost=1.0, weight=None):
# Track what the index thinks this field is called.
self.instance_name = None
self.model_attr = model_attr
self.use_template = use_template
self.template_name = template_name
self.document = document
self.indexed = indexed
self.stored = stored
self.faceted = faceted
self._default = default
self.null = null
self.index_fieldname = index_fieldname
self.boost = weight or boost
self.is_multivalued = False
# We supply the facet_class for making it easy to create a faceted
# field based off of this field.
self.facet_class = facet_class
if self.facet_class is None:
self.facet_class = FacetCharField
self.set_instance_name(None)
def set_instance_name(self, instance_name):
self.instance_name = instance_name
if self.index_fieldname is None:
self.index_fieldname = self.instance_name
def has_default(self):
"""Returns a boolean of whether this field has a default value."""
return self._default is not NOT_PROVIDED
@property
def default(self):
"""Returns the default value for the field."""
if callable(self._default):
return self._default()
return self._default
def prepare(self, obj):
"""
Takes data from the provided object and prepares it for storage in the
index.
"""
# Give priority to a template.
if self.use_template:
return self.prepare_template(obj)
elif self.model_attr is not None:
# Check for `__` in the field for looking through the relation.
attrs = self.model_attr.split('__')
current_object = obj
for attr in attrs:
if not hasattr(current_object, attr):
raise SearchFieldError("The model '%s' does not have a model_attr '%s'." % (repr(current_object), attr))
current_object = getattr(current_object, attr, None)
if current_object is None:
if self.has_default():
current_object = self._default
# Fall out of the loop, given any further attempts at
# accesses will fail miserably.
break
elif self.null:
current_object = None
# Fall out of the loop, given any further attempts at
# accesses will fail miserably.
break
else:
raise SearchFieldError("The model '%s' combined with model_attr '%s' returned None, but doesn't allow a default or null value." % (repr(obj), self.model_attr))
if callable(current_object):
return current_object()
return current_object
if self.has_default():
return self.default
else:
return None
def prepare_template(self, obj):
"""
Flattens an object for indexing.
This loads a template
(``search/indexes/{app_label}/{model_name}_{field_name}.txt``) and
returns the result of rendering that template. ``object`` will be in
its context.
"""
if self.instance_name is None and self.template_name is None:
raise SearchFieldError("This field requires either its instance_name variable to be populated or an explicit template_name in order to load the correct template.")
if self.template_name is not None:
template_names = self.template_name
if not isinstance(template_names, (list, tuple)):
template_names = [template_names]
else:
app_label, model_name = get_model_ct_tuple(obj)
template_names = ['search/indexes/%s/%s_%s.txt' % (app_label, model_name, self.instance_name)]
t = loader.select_template(template_names)
return t.render(Context({'object': obj}).flatten())
def convert(self, value):
"""
Handles conversion between the data found and the type of the field.
Extending classes should override this method and provide correct
data coercion.
"""
return value
class CharField(SearchField):
field_type = 'string'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetCharField
super(CharField, self).__init__(**kwargs)
def prepare(self, obj):
return self.convert(super(CharField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
return six.text_type(value)
class LocationField(SearchField):
field_type = 'location'
def prepare(self, obj):
from haystack.utils.geo import ensure_point
value = super(LocationField, self).prepare(obj)
if value is None:
return None
pnt = ensure_point(value)
pnt_lng, pnt_lat = pnt.get_coords()
return "%s,%s" % (pnt_lat, pnt_lng)
def convert(self, value):
from haystack.utils.geo import ensure_point, Point
if value is None:
return None
if hasattr(value, 'geom_type'):
value = ensure_point(value)
return value
if isinstance(value, six.string_types):
lat, lng = value.split(',')
elif isinstance(value, (list, tuple)):
# GeoJSON-alike
lat, lng = value[1], value[0]
elif isinstance(value, dict):
lat = value.get('lat', 0)
lng = value.get('lon', 0)
value = Point(float(lng), float(lat))
return value
class NgramField(CharField):
field_type = 'ngram'
def __init__(self, **kwargs):
if kwargs.get('faceted') is True:
raise SearchFieldError("%s can not be faceted." % self.__class__.__name__)
super(NgramField, self).__init__(**kwargs)
class EdgeNgramField(NgramField):
field_type = 'edge_ngram'
class IntegerField(SearchField):
field_type = 'integer'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetIntegerField
super(IntegerField, self).__init__(**kwargs)
def prepare(self, obj):
return self.convert(super(IntegerField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
return int(value)
class FloatField(SearchField):
field_type = 'float'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetFloatField
super(FloatField, self).__init__(**kwargs)
def prepare(self, obj):
return self.convert(super(FloatField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
return float(value)
class DecimalField(SearchField):
field_type = 'string'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetDecimalField
super(DecimalField, self).__init__(**kwargs)
def prepare(self, obj):
return self.convert(super(DecimalField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
return six.text_type(value)
class BooleanField(SearchField):
field_type = 'boolean'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetBooleanField
super(BooleanField, self).__init__(**kwargs)
def prepare(self, obj):
return self.convert(super(BooleanField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
return bool(value)
class DateField(SearchField):
field_type = 'date'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetDateField
super(DateField, self).__init__(**kwargs)
def prepare(self, obj):
return self.convert(super(DateField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
if isinstance(value, six.string_types):
match = DATE_REGEX.search(value)
if match:
data = match.groupdict()
return datetime_safe.date(int(data['year']), int(data['month']), int(data['day']))
else:
raise SearchFieldError("Date provided to '%s' field doesn't appear to be a valid date string: '%s'" % (self.instance_name, value))
return value
class DateTimeField(SearchField):
field_type = 'datetime'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetDateTimeField
super(DateTimeField, self).__init__(**kwargs)
def prepare(self, obj):
return self.convert(super(DateTimeField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
if isinstance(value, six.string_types):
match = DATETIME_REGEX.search(value)
if match:
data = match.groupdict()
return datetime_safe.datetime(int(data['year']), int(data['month']), int(data['day']), int(data['hour']), int(data['minute']), int(data['second']))
else:
raise SearchFieldError("Datetime provided to '%s' field doesn't appear to be a valid datetime string: '%s'" % (self.instance_name, value))
return value
class MultiValueField(SearchField):
field_type = 'string'
def __init__(self, **kwargs):
if kwargs.get('facet_class') is None:
kwargs['facet_class'] = FacetMultiValueField
if kwargs.get('use_template') is True:
raise SearchFieldError("'%s' fields can not use templates to prepare their data." % self.__class__.__name__)
super(MultiValueField, self).__init__(**kwargs)
self.is_multivalued = True
def prepare(self, obj):
return self.convert(super(MultiValueField, self).prepare(obj))
def convert(self, value):
if value is None:
return None
return list(value)
class FacetField(SearchField):
"""
``FacetField`` is slightly different than the other fields because it can
work in conjunction with other fields as its data source.
Accepts an optional ``facet_for`` kwarg, which should be the field name
(not ``index_fieldname``) of the field it should pull data from.
"""
instance_name = None
def __init__(self, **kwargs):
handled_kwargs = self.handle_facet_parameters(kwargs)
super(FacetField, self).__init__(**handled_kwargs)
def handle_facet_parameters(self, kwargs):
if kwargs.get('faceted', False):
raise SearchFieldError("FacetField (%s) does not accept the 'faceted' argument." % self.instance_name)
if not kwargs.get('null', True):
raise SearchFieldError("FacetField (%s) does not accept False for the 'null' argument." % self.instance_name)
if not kwargs.get('indexed', True):
raise SearchFieldError("FacetField (%s) does not accept False for the 'indexed' argument." % self.instance_name)
if kwargs.get('facet_class'):
raise SearchFieldError("FacetField (%s) does not accept the 'facet_class' argument." % self.instance_name)
self.facet_for = None
self.facet_class = None
# Make sure the field is nullable.
kwargs['null'] = True
if 'facet_for' in kwargs:
self.facet_for = kwargs['facet_for']
del(kwargs['facet_for'])
return kwargs
def get_facet_for_name(self):
return self.facet_for or self.instance_name
class FacetCharField(FacetField, CharField):
pass
class FacetIntegerField(FacetField, IntegerField):
pass
class FacetFloatField(FacetField, FloatField):
pass
class FacetDecimalField(FacetField, DecimalField):
pass
class FacetBooleanField(FacetField, BooleanField):
pass
class FacetDateField(FacetField, DateField):
pass
class FacetDateTimeField(FacetField, DateTimeField):
pass
class FacetMultiValueField(FacetField, MultiValueField):
pass
