def resolve_field_of_path(manager, field_path, return_related_models=False):
"""
Resolves a field for a manager and field_path that might have __'s indicating relations
:param manager:
:param field_path:
:param return_related_models
:return: Either the resolved field, or if return_related_models is True this
instead returns a tuple of the resolve field and the related model, the latter being non-null
only for foreign key properties or id properties that represent foreign keys
(e.g. built_form or built_form_id, respectively, would return the tuple
(ForeignKey, BuiltForm) or (AutoField, BuiltForm), respectively
"""
parts = field_path.split('__')
model = manager.model
related_model = None
while len(parts) > 0:
part = parts.pop(0)
# Each part either results in a model or field. Field is the end-case
# Work around Django init bug for dynamic models
clear_many_cache(model)
model_or_field_tuple = model._meta._name_map.get(part)
if not model_or_field_tuple:
# It might be that the part represents the attname of a field, not the field name
# This is true for ForeignKey relationships
# Find the matching field, and if found find the related model's id field
related_field_tuple = get_value_of_first_matching_key(
lambda name, field: part == field[0].attname
if hasattr(field[0], 'attname') else False,
model._meta._name_map)
if related_field_tuple:
model_or_field_tuple = related_field_tuple[
0].rel.to._meta._name_map['id']
related_model = related_field_tuple[0].rel.to
if not model_or_field_tuple:
# Something went wrong, give up
return None
if isinstance(model_or_field_tuple[0], RelatedField):
# RelatedField. Recurse unless we are out of parts of the field_path
if len(parts) > 0:
# Continue on
model = model_or_field_tuple[0].rel.to
continue
else:
related_model = model_or_field_tuple[0].rel.to
elif isinstance(model_or_field_tuple[0], RelatedObject):
# RelatedObject. Always recurse
model = model_or_field_tuple[0].model
continue
# RelatedField with no parts left or simple Field type
return model_or_field_tuple[0] if not return_related_models else\
(model_or_field_tuple[0], related_model or None)
def resolve_field_of_path(manager, field_path, return_related_models=False):
"""
Resolves a field for a manager and field_path that might have __'s indicating relations
:param manager:
:param field_path:
:param return_related_models
:return: Either the resolved field, or if return_related_models is True this
instead returns a tuple of the resolve field and the related model, the latter being non-null
only for foreign key properties or id properties that represent foreign keys
(e.g. built_form or built_form_id, respectively, would return the tuple
(ForeignKey, BuiltForm) or (AutoField, BuiltForm), respectively
"""
parts = field_path.split('__')
model = manager.model
related_model = None
while len(parts) > 0:
part = parts.pop(0)
# Each part either results in a model or field. Field is the end-case
# Work around Django init bug for dynamic models
clear_many_cache(model)
model_or_field_tuple = model._meta._name_map.get(part)
if not model_or_field_tuple:
# It might be that the part represents the attname of a field, not the field name
# This is true for ForeignKey relationships
# Find the matching field, and if found find the related model's id field
related_field_tuple = get_value_of_first_matching_key(
lambda name, field: part == field[0].attname if hasattr(field[0], 'attname') else False,
model._meta._name_map)
if related_field_tuple:
model_or_field_tuple = related_field_tuple[0].rel.to._meta._name_map['id']
related_model = related_field_tuple[0].rel.to
if not model_or_field_tuple:
# Something went wrong, give up
return None
if isinstance(model_or_field_tuple[0], RelatedField):
# RelatedField. Recurse unless we are out of parts of the field_path
if len(parts) > 0:
# Continue on
model = model_or_field_tuple[0].rel.to
continue
else:
related_model = model_or_field_tuple[0].rel.to
elif isinstance(model_or_field_tuple[0], RelatedObject):
# RelatedObject. Always recurse
model = model_or_field_tuple[0].model
continue
# RelatedField with no parts left or simple Field type
return model_or_field_tuple[0] if not return_related_models else\
(model_or_field_tuple[0], related_model or None)
def resolve_related_model_pk(db_entity_key):
related_model = config_entity.db_entity_feature_class(db_entity_key)
# The common Geography class
geography_class = feature_class_creator.common_geography_class(related_model)
geography_scope = feature_class_creator.common_geography_scope(related_model)
logger.warn("Resolved geography scope %s", geography_scope)
# Find the geographies ManyToMany fields that relates this model to the related_model
# via a Geography class. Which geography class depends on their common geography scope
geographies_field = feature_class_creator.geographies_field(geography_scope)
try:
# Find the queryable field name from the geography class to the related model
related_model_geographies_field_name = resolve_queryable_name_of_type(geography_class, related_model)
except:
# Sometimes the geography class hasn't had its fields cached properly. Fix here
clear_many_cache(geography_class)
related_model_geographies_field_name = resolve_queryable_name_of_type(geography_class, related_model)
return "%s__%s__pk" % (geographies_field.name, related_model_geographies_field_name)
def resolve_related_model_pk(db_entity_key):
related_model = config_entity.db_entity_feature_class(db_entity_key)
# The common Geography class
geography_class = feature_class_creator.common_geography_class(related_model)
geography_scope = feature_class_creator.common_geography_scope(related_model)
logger.warn("Resolved geography scope %s", geography_scope)
# Find the geographies ManyToMany fields that relates this model to the related_model
# via a Geography class. Which geography class depends on their common geography scope
geographies_field = feature_class_creator.geographies_field(geography_scope)
try:
# Find the queryable field name from the geography class to the related model
related_model_geographies_field_name = resolve_queryable_name_of_type(geography_class, related_model)
except:
# Sometimes the geography class hasn't had its fields cached properly. Fix here
clear_many_cache(geography_class)
related_model_geographies_field_name = resolve_queryable_name_of_type(geography_class, related_model)
return '%s__%s__pk' % (geographies_field.name, related_model_geographies_field_name)
def related_resource_field(cls, related_field_name, relationship_dict, no_cache=False):
"""
Returns a tuple of the related_field resource name and resource field. ManyToMany and ForeignKey is currently supported
:param related_field_name: The related name on the model class
:param relationship_dict: A dict describing the relationship with keys
descriptor: The related ReverseSingleRelatedObjectDescriptor (or similar) of the model class. Expected is an instance of models.ManyToMany, or models.ForeignKey
field: (Alternative to descriptor. A related Field
full: Tastypie field param
null: Tastypie field param
no_cache: Don't use a cached resource for this field's dynamic resource class
use_version_fields: Explained below
:param no_cache: Default False. True to avoid using a cached resource class
:return: A tuple with the field.name or singularized version and the created resource field.
All fields created have full=False and null=True with the assumption that the value is optional and a need not be nested
"""
cls.logger.info("Resolving related resource field with name %s and no_cache %s" % (related_field_name, no_cache))
callable_attribute = None
full = None
null = True
use_version_fields = False
if isinstance(relationship_dict, Field):
# related_descriptor is a Field
related_field = relationship_dict
elif isinstance(relationship_dict, dict):
related_field = relationship_dict['descriptor'].field if\
relationship_dict.get('descriptor') else\
relationship_dict['field']
callable_attribute = relationship_dict.get('callable_attribute')
full = relationship_dict.get('full', False)
null = relationship_dict.get('null', True)
no_cache = relationship_dict.get('no_cache', True)
# Enable lookup of this field and the resource fields of Revisionable._version_field_dict
use_version_fields = relationship_dict.get('use_version_fields', False)
else:
# ReverseManyToMany and similar
related_field = relationship_dict.field
related_resource_class = FootprintResource.resolve_resource_class(
related_field.rel.to,
no_cache=no_cache,
use_version_fields=use_version_fields,
only_abstract_resources=False)
# Clear the related object field caches in case it didn't pick up the dynamic many-to-many field of cls's model
clear_many_cache(related_field.rel.to)
name = related_field.name or related_field_name
if callable_attribute:
# Explicit callable_attribute defined for this attribute
attribute = callable_attribute
elif use_version_fields:
# If this is set it means we set the Revisionable._version_field_dict
# Tell the related field to look for a _version_field_dict key matching the attribute name
# If found return that, otherwise just return the normal object field value
def get_attribute(bundle):
obj = (bundle.obj._version_field_dict if
hasattr(bundle.obj, '_version_field_dict') else
dict())\
.get(name, getattr(bundle.obj, name))
return obj
attribute = get_attribute
else:
# Simply use the field name as the attribute
attribute = name
if isinstance(related_field, models.ManyToManyField):
field_class = fields.ToManyField
elif isinstance(related_field, models.ForeignKey):
field_class = fields.ToOneField
else:
raise Exception("Expected ToManyField or ToOneField. Got %s" % related_field.__class__.__name__)
return [name, field_class(related_resource_class, attribute=attribute, full=full, null=null)]
def related_resource_field(cls, related_field_name, relationship_dict, no_cache=False):
"""
Returns a tuple of the related_field resource name and resource field. ManyToMany and ForeignKey is currently supported
:param related_field_name: The related name on the model class
:param relationship_dict: A dict describing the relationship with keys
descriptor: The related ReverseSingleRelatedObjectDescriptor (or similar) of the model class. Expected is an instance of models.ManyToMany, or models.ForeignKey
field: (Alternative to descriptor. A related Field
full: Tastypie field param
null: Tastypie field param
no_cache: Don't use a cached resource for this field's dynamic resource class
use_version_fields: Explained below
:param no_cache: Default False. True to avoid using a cached resource class
:return: A tuple with the field.name or singularized version and the created resource field.
All fields created have full=False and null=True with the assumption that the value is optional and a need not be nested
"""
cls.logger.info("Resolving related resource field with name %s and no_cache %s" % (related_field_name, no_cache))
callable_attribute = None
full = None
null = True
use_version_fields = False
if isinstance(relationship_dict, Field):
# related_descriptor is a Field
related_field = relationship_dict
elif isinstance(relationship_dict, dict):
related_field = relationship_dict['descriptor'].field if\
relationship_dict.get('descriptor') else\
relationship_dict['field']
callable_attribute = relationship_dict.get('callable_attribute')
full = relationship_dict.get('full', False)
null = relationship_dict.get('null', True)
no_cache = relationship_dict.get('no_cache', True)
# Enable lookup of this field and the resource fields of Revisionable._version_field_dict
use_version_fields = relationship_dict.get('use_version_fields', False)
else:
# ReverseManyToMany and similar
related_field = relationship_dict.field
related_resource_class = FootprintResource.resolve_resource_class(
related_field.rel.to,
no_cache=no_cache,
use_version_fields=use_version_fields,
only_abstract_resources=False)
# Clear the related object field caches in case it didn't pick up the dynamic many-to-many field of cls's model
clear_many_cache(related_field.rel.to)
name = related_field.name or related_field_name
if callable_attribute:
# Explicit callable_attribute defined for this attribute
attribute = callable_attribute
elif use_version_fields:
# If this is set it means we set the Revisionable._version_field_dict
# Tell the related field to look for a _version_field_dict key matching the attribute name
# If found return that, otherwise just return the normal object field value
def get_attribute(bundle):
obj = (bundle.obj._version_field_dict if
hasattr(bundle.obj, '_version_field_dict') else
dict())\
.get(name, getattr(bundle.obj, name))
return obj
attribute = get_attribute
else:
# Simply use the field name as the attribute
attribute = name
if isinstance(related_field, models.ManyToManyField):
field_class = fields.ToManyField
elif isinstance(related_field, models.ForeignKey):
field_class = fields.ToOneField
else:
raise Exception("Expected ToManyField or ToOneField. Got %s" % related_field.__class__.__name__)
return [name, field_class(related_resource_class, attribute=attribute, full=full, null=null)]
