Edit File: properties.cpython-37.pyc
B ��4]#+ � @ s� d Z ddlmZ ddlmZ ddlmZ ddlmZ ddlm Z dd lm Z dd lmZ dd l m Z d gZ e jG d d � d e��ZdS )z|MapperProperty implementations. This is a private module which defines the behavior of individual ORM- mapped attributes. � )�absolute_import� )� attributes)�PropComparator)�StrategizedProperty)�_orm_full_deannotate� )�log)�util)� expression�ColumnPropertyc s� e Zd ZdZdZdZejdd�� fdd��Ze� dd �d d � �Z d d � Z e dd� �Z dd� Z� fdd�Zdd� Zejfdd�Zdd� ZG dd� deje�Zd d � Z� ZS ) r z�Describes an object attribute that corresponds to a table column. Public constructor is the :func:`.orm.column_property` function. �column)� _orig_columns�columns�group�deferred� instrument�comparator_factory� descriptor� extension�active_history�expire_on_flush�info�doc� strategy_keyZ_creation_orderZ _is_polymorphic_discriminatorZ_mapped_by_synonymZ_deferred_column_loader)z0.7z�:class:`.AttributeExtension` is deprecated in favor of the :class:`.AttributeEvents` listener interface. The :paramref:`.column_property.extension` parameter will be removed in a future release.)r c sN t t| ��� dd� |D �| _dd� |D �| _|�dd�| _|�dd�| _|�dd �| _|�d | j j �| _ |�d d�| _ |�d d�| _ |�d d�| _|�dd �| _d|kr�|�d�| _d|kr�|�d�| _n6x4t| j�D ] }t|dd�}|dk r�|| _P q�W d| _|�r*td| j jd�t|�� ��f ��t�| � d| jfd| jff| _dS )a\ Provide a column-level property for use with a Mapper. Column-based properties can normally be applied to the mapper's ``properties`` dictionary using the :class:`.Column` element directly. Use this function when the given column is not directly present within the mapper's selectable; examples include SQL expressions, functions, and scalar SELECT queries. Columns that aren't present in the mapper's selectable won't be persisted by the mapper and are effectively "read-only" attributes. :param \*cols: list of Column objects to be mapped. :param active_history=False: When ``True``, indicates that the "previous" value for a scalar attribute should be loaded when replaced, if not already loaded. Normally, history tracking logic for simple non-primary-key scalar values only needs to be aware of the "new" value in order to perform a flush. This flag is available for applications that make use of :func:`.attributes.get_history` or :meth:`.Session.is_modified` which also need to know the "previous" value of the attribute. :param comparator_factory: a class which extends :class:`.ColumnProperty.Comparator` which provides custom SQL clause generation for comparison operations. :param group: a group name for this property when marked as deferred. :param deferred: when True, the column property is "deferred", meaning that it does not load immediately, and is instead loaded when the attribute is first accessed on an instance. See also :func:`~sqlalchemy.orm.deferred`. :param doc: optional string that will be applied as the doc on the class-bound descriptor. :param expire_on_flush=True: Disable expiry on flush. A column_property() which refers to a SQL expression (and not a single table-bound column) is considered to be a "read only" property; populating it has no effect on the state of data, and it can only return database state. For this reason a column_property()'s value is expired whenever the parent object is involved in a flush, that is, has any kind of "dirty" state within a flush. Setting this parameter to ``False`` will have the effect of leaving any existing value present after the flush proceeds. Note however that the :class:`.Session` with default expiration settings still expires all attributes after a :meth:`.Session.commit` call, however. :param info: Optional data dictionary which will be populated into the :attr:`.MapperProperty.info` attribute of this object. :param extension: an :class:`.AttributeExtension` instance, or list of extensions, which will be prepended to the list of attribute listeners for the resulting descriptor placed on the class. c S s g | ]}t �|��qS � )r �_labeled)�.0�cr r �L/opt/alt/python37/lib64/python3.7/site-packages/sqlalchemy/orm/properties.py� <listcomp>� s z+ColumnProperty.__init__.<locals>.<listcomp>c S s g | ]}t �t|���qS r )r r r )r r r r r r � s r Nr FZ _instrumentTr r r r r r r z.%s received unexpected keyword argument(s): %sz, r ) �superr �__init__r r �popr r r � __class__� Comparatorr r r r r r r �reversed�getattr� TypeError�__name__�join�sorted�keysr Zset_creation_orderr )�selfr �kwargs�colr )r$ r r r" : s: K zColumnProperty.__init__zsqlalchemy.orm.statezsqlalchemy.orm.strategiesc C s |j �| jj|�| j�| j�S )N)Z InstanceStateZ"_instance_level_callable_processor�parentZ class_managerZLoadDeferredColumns�key)r- �stateZ strategiesr r r �&_memoized_attr__deferred_column_loader� s z5ColumnProperty._memoized_attr__deferred_column_loaderc C s | j S )zsAllow the ColumnProperty to work in expression before it is turned into an instrumented attribute. )r )r- r r r �__clause_element__� s z!ColumnProperty.__clause_element__c C s | j d S )zJReturn the primary column or expression for this ColumnProperty. r )r )r- r r r r � s zColumnProperty.expressionc C s0 | j s d S tj|j| j| �| |�|| jd� d S )N)Z comparator� parententityr )r r Zregister_descriptor�class_r1 r r )r- Zmapperr r r �instrument_class� s z ColumnProperty.instrument_classc sZ t t| ��� t| j�dkrVt| jj��| j�rVt � d| j| jd | jd | j f � d S )Nr z�On mapper %s, primary key column '%s' is being combined with distinct primary key column '%s' in attribute '%s'. Use explicit properties to give each column its own mapped attribute name.r ) r! r �do_init�lenr �setr0 Z primary_key� issupersetr �warnr1 )r- )r$ r r r8 � s zColumnProperty.do_initc C s t | j| j| j| jd��S )N)r r r )r r r r r )r- r r r �copy� s zColumnProperty.copyc C s |� | j�j|||d�S )N)�passive)�get_implr1 Zget_committed_value)r- r2 Zdict_r r> r r r � _getcommitted� s z ColumnProperty._getcommittedc C st | j s d S | j|krL|| j } |s.| || j< qp|�| j�} | �||| d � n$|jrp| j|krp|j|| jgdd� d S )NT)Z no_loader)r r1 r? r: Z has_identityZ_expire_attributes) r- ZsessionZ source_stateZ source_dictZ dest_stateZ dest_dict�load� _recursiveZ_resolve_conflict_map�value�implr r r �merge� s zColumnProperty.mergec @ s< e Zd ZdZdZdd� Zdd� Zdd� Zd d � Zd d � Z d S )zColumnProperty.Comparatora� Produce boolean, comparison, and other operators for :class:`.ColumnProperty` attributes. See the documentation for :class:`.PropComparator` for a brief overview. .. seealso:: :class:`.PropComparator` :class:`.ColumnOperators` :ref:`types_operators` :attr:`.TypeEngine.comparator_factory` )r4 r c C s8 | j r| � | jjd �S | jjd �| j| jd��S d S )Nr )r5 Z parentmapper)Zadapter�propr Z _annotateZ _parententity)r- r r r �#_memoized_method___clause_element__ s z=ColumnProperty.Comparator._memoized_method___clause_element__c C s, | � � }y|jS tk r& | jjS X d S )N)r4 r �AttributeErrorrF )r- Zcer r r �_memoized_attr_info, s z-ColumnProperty.Comparator._memoized_attr_infoc C s t | �� |�S )z�proxy attribute access down to the mapped column. this allows user-defined comparison methods to be accessed. )r' r4 )r- r1 r r r �_fallback_getattr3 s z+ColumnProperty.Comparator._fallback_getattrc O s || � � f|�|�S )N)r4 )r- �op�otherr. r r r �operate: s z!ColumnProperty.Comparator.operatec K s | � � }||�||�|f|�S )N)r4 Z _bind_param)r- rK rL r. r/ r r r �reverse_operate= s z)ColumnProperty.Comparator.reverse_operateN) r) � __module__� __qualname__�__doc__� __slots__rG rI rJ rM rN r r r r r% s r% c C s t | jjj�d | j S )N�.)�strr0 r6 r) r1 )r- r r r �__str__A s zColumnProperty.__str__)r) rO rP rQ Zstrategy_wildcard_keyrR r Zdeprecated_paramsr" Z dependenciesr3 r4 �propertyr r7 r8 r= r Z PASSIVE_OFFr@ rE Z MemoizedSlotsr r% rU � __classcell__r r )r$ r r s t 7N)rQ � __future__r � r Z interfacesr r r r r Zsqlr �__all__Z class_loggerr r r r r �<module> s