_V+@sdZddlmZddlZddlmZddlmZddlm Z ddl m Z dd l m Z Gd d d eZGd d d eZGdddeZGdddeZdS)al "Rel objects" for related fields. "Rel objects" (for lack of a better name) carry information about the relation modeled by a related field and provide some utility functions. They're stored in the ``remote_field`` attribute of the field. They also act as reverse fields for the purposes of the Meta API because they're the closest concept currently available. )unicode_literalsN) exceptions)RemovedInDjango20Warning) smart_text)cached_property)BLANK_CHOICE_DASHc@seZdZdZdZdZdZdZdZdddddddZ e ddZ e d d Z e d d Ze d dZe ddZe ddZe ddZe ddZe ddZe ddZddZddZdd Ze d!d"Zd#d$Zdedd%d&Zdd'd(Zd)d*Zd+d,Zd-d.Z d/d0Z!dd1d2Z"d3d4Z#d5d6Z$dS)7ForeignObjectRelz Used by ForeignObject to store information about the relation. ``_meta.get_fields()`` returns this class to provide access to the field flags for the reverse relation. TFNcCsg||_||_||_||_|dkr6in||_||_||_d|_d|_dS)NFT) fieldmodel related_namerelated_query_namelimit_choices_to parent_link on_delete symmetricalmultiple)selfr tor r rrrrI/tmp/pip-build-ghmbqnp_/Django/django/db/models/fields/reverse_related.py__init__*s       zForeignObjectRel.__init__cCstjdtd|jS)Nz\Usage of ForeignObjectRel.to attribute has been deprecated. Use the model attribute instead.)warningswarnrr )rrrrr;s zForeignObjectRel.tocCs |jS)N) is_hidden)rrrrhiddenCszForeignObjectRel.hiddencCs |jjS)N)r r )rrrrnameGszForeignObjectRel.namecCs|jS)N)r )rrrr remote_fieldKszForeignObjectRel.remote_fieldcCs?|jdj}t|dkr7tjdn|dS)z When filtering against this relation, returns the field on the remote model against which the filtering should happen. rz1Can't use target_field for multicolumn relations.r) get_path_info target_fieldslenrZ FieldError)rr!rrr target_fieldOszForeignObjectRel.target_fieldcCs%|jjstdn|jjS)NzVThis property can't be accessed before self.field.contribute_to_class has been called.)r r AttributeError)rrrr related_modelZs  zForeignObjectRel.related_modelcCs |jjS)N)r many_to_many)rrrrr&aszForeignObjectRel.many_to_manycCs |jjS)N)r one_to_many)rrrr many_to_oneeszForeignObjectRel.many_to_onecCs |jjS)N)r r()rrrrr'iszForeignObjectRel.one_to_manycCs |jjS)N)r one_to_one)rrrrr)mszForeignObjectRel.one_to_onecCs|jj||S)N)r get_prep_lookup)r lookup_namevaluerrrr*qsz ForeignObjectRel.get_prep_lookupcCs|jj|S)N)r get_lookup)rr+rrrr-tszForeignObjectRel.get_lookupcCs |jjS)N)r get_internal_type)rrrrr.wsz"ForeignObjectRel.get_internal_typecCs |jjS)N)r db_type)rrrrr/zszForeignObjectRel.db_typecCs,dt|j|jjj|jjjfS)Nz <%s: %s.%s>)type__name__r%_meta app_label model_name)rrrr__repr__~s  zForeignObjectRel.__repr__cCsk|r |ng}|jjj}|rP|jidd|jjj6}ndd|D}||S)a Return choices with a default blank choices included, for use as SelectField choices for this field. Analog of django.db.models.fields.Field.get_choices(), provided initially for utilization by RelatedFieldListFilter. Fz %s__isnullcSs(g|]}|jt|fqSr)Z _get_pk_valr).0xrrr s z0ForeignObjectRel.get_choices..)r%Z_default_managerallZcomplex_filterr2r4)rZ include_blankZ blank_choiceZlimit_to_currently_relatedZ first_choiceZquerysetlstrrr get_choicess  zForeignObjectRel.get_choicescCs|jj||d|d|S)N connectionprepared)r get_db_prep_lookup)rZ lookup_typer,r<r=rrrr>sz#ForeignObjectRel.get_db_prep_lookupcCs t|jo|jddkS)z$Should the related object be hidden?r+r)boolr )rrrrrszForeignObjectRel.is_hiddencCs |jjS)N)r Zget_reverse_joining_columns)rrrrget_joining_columnssz$ForeignObjectRel.get_joining_columnscCs|jj|||S)N)r get_extra_restriction)rZ where_classaliasZ related_aliasrrrrBsz&ForeignObjectRel.get_extra_restrictioncCs d|_dS)z Set the related field's name, this is not available until later stages of app loading, so set_field_name is called from set_attributes_from_rel() N) field_name)rrrrset_field_nameszForeignObjectRel.set_field_namecCs|r|jn |jj}|p'|j}|jrR|jrR||jkrRdSn|jrb|jS|jr|ji|jjd6|j jd6S|j|jrdndS)Nr4r3Z_set) r2r%rrr r Zdefault_related_namer4lowerr3)rr optsrrrget_accessor_names    z"ForeignObjectRel.get_accessor_namecCsd|jS)Nz _%s_cache)rI)rrrrget_cache_nameszForeignObjectRel.get_cache_namecCs |jjS)N)r Zget_reverse_path_info)rrrrr szForeignObjectRel.get_path_info)%r1 __module__ __qualname____doc__Z auto_createdconcreteeditableZ is_relationnullrpropertyrrrrrr#r%r&r(r'r)r*r-r.r/r5rr;r>rrArBrErIrJr rrrrr sB           r cs[eZdZdZdddddfddZddZdd Zd d ZS) ManyToOneRela+ Used by the ForeignKey field to store information about the relation. ``_meta.get_fields()`` returns this class to provide access to the field flags for the reverse relation. Note: Because we somewhat abuse the Rel objects by using them as reverse fields we get the funny situation where ``ManyToOneRel.many_to_one == False`` and ``ManyToOneRel.one_to_many == True``. This is unfortunate but the actual ManyToOneRel class is a private API and there is work underway to turn reverse relations into actual fields. NFc sDtt|j||d|d|d|d|d|||_dS)Nr r rrr)superrRrrD) rr rrDr r rrr) __class__rrrs zManyToOneRel.__init__cCs#|jj}|jdd|S)Nr%)__dict__copypop)rstaterrr __getstate__szManyToOneRel.__getstate__cCs>|jjj|j}|js:tjd|jn|S)zY Return the Field in the 'to' object to which this relationship is tied. zNo related field named '%s')r r2 get_fieldrDrNrZFieldDoesNotExist)rr rrrget_related_fields   zManyToOneRel.get_related_fieldcCs"|jp|jjjj|_dS)N)rDr r2pkr)rrrrrEszManyToOneRel.set_field_name)r1rKrLrMrrYr[rErr)rTrrRs   rRcs7eZdZdZdddddfddZS) OneToOneRelz Used by OneToOneField to store information about the relation. ``_meta.get_fields()`` returns this class to provide access to the field flags for the reverse relation. NFc sGtt|j|||d|d|d|d|d|d|_dS)Nr r rrrF)rSr]rr) rr rrDr r rrr)rTrrrs zOneToOneRel.__init__)r1rKrLrMrrr)rTrr]s r]c sIeZdZdZdddddddfddZddZS) ManyToManyRelz Used by ManyToManyField to store information about the relation. ``_meta.get_fields()`` returns this class to provide access to the field flags for the reverse relation. NTc stt|j||d|d|d||rG| rGtdn||_|rl| rltdn||_||_| |_dS)Nr r rz4Can't supply a through model and db_constraint=Falsez5Cannot specify through_fields without a through model)rSr^r ValueErrorthroughthrough_fieldsr db_constraint) rr rr r rrr`rarb)rTrrrs      zManyToManyRel.__init__cCs{|jj}|jr.|j|jd}nBx?|jD]4}t|dd}|r8|j|jkr8Pq8q8W|jdS)z Return the field in the 'to' object to which this relationship is tied. Provided for symmetry with ManyToOneRel. rrN)r`r2rarZfieldsgetattrr Zforeign_related_fields)rrHr relrrrr[.s  zManyToManyRel.get_related_field)r1rKrLrMrr[rr)rTrr^s  r^)rM __future__rrZ django.corerZdjango.utils.deprecationrZdjango.utils.encodingrZdjango.utils.functionalrrFrobjectr rRr]r^rrrr s /