Edit File: base.cpython-37.pyc
B ��4] & � @ s� d Z ddlmZ ddlZddlmZ ddlmZ ddlmZ dd lm Z e � e �Z d d � Z G d d � d e�ZG dd� de�ZG dd� de�Zdd� Zdd� ZG dd� de �ee��ZG dd� de�ZG dd� de�ZdS ) a� Base implementation classes. The public-facing ``Events`` serves as the base class for an event interface; its public attributes represent different kinds of events. These attributes are mirrored onto a ``_Dispatch`` class, which serves as a container for collections of listener functions. These collections are represented both at the class level of a particular ``_Dispatch`` class as well as within instances of ``_Dispatch``. � )�absolute_importN� )�_ClsLevelDispatch)�_EmptyListener)�_JoinedListener� )�utilc C s | � d� o| dkS )N�_�dispatch)� startswith)�name� r �H/opt/alt/python37/lib64/python3.7/site-packages/sqlalchemy/event/base.py�_is_event_name s r c @ s e Zd ZdZdd� ZdS )�_UnpickleDispatchz�Serializable callable that re-generates an instance of :class:`_Dispatch` given a particular :class:`.Events` subclass. c C s8 x2|j D ] }d|jkr|jd j�|�S qW td��d S )Nr z*No class with a 'dispatch' member present.)�__mro__�__dict__r � _for_class�AttributeError)�self� _instance_cls�clsr r r �__call__) s z_UnpickleDispatch.__call__N)�__name__� __module__� __qualname__�__doc__r r r r r r # s r c @ sx e Zd ZdZdZe�� Zddd�Zdd� Z e dd � �Z e d d � �Z d d � Z dd� Zdd� Zdd� Zddd�Zdd� ZdS )� _Dispatcha; Mirror the event listening definitions of an Events class with listener collections. Classes which define a "dispatch" member will return a non-instantiated :class:`._Dispatch` subclass when the member is accessed at the class level. When the "dispatch" member is accessed at the instance level of its owner, an instance of the :class:`._Dispatch` class is returned. A :class:`._Dispatch` class is generated for each :class:`.Events` class defined, by the :func:`._create_dispatcher_class` function. The original :class:`.Events` classes remain untouched. This decouples the construction of :class:`.Events` subclasses from the implementation used by the event internals, and allows inspecting tools like Sphinx to work in an unsurprising way against the public API. )�_parentr r �_empty_listenersNc sb || _ � | _� rXy| j� | _W q^ tk rT � fdd�|jD � | _| j� < Y q^X ni | _d S )Nc s i | ]}t |� �|j�qS r )r r )�.0�ls)� instance_clsr r � <dictcomp>W s z&_Dispatch.__init__.<locals>.<dictcomp>)r r �_empty_listener_regr �KeyError�_event_descriptors)r �parentr" r )r" r �__init__M s z_Dispatch.__init__c C sB y| j | }W n tk r* t|��Y nX t| |j|� |S d S )N)r r% r �setattrr )r r r! r r r � __getattr__^ s z_Dispatch.__getattr__c c s x| j D ]}t| |�V qW d S )N)� _event_names�getattr)r �kr r r r& i s z _Dispatch._event_descriptorsc C s | j jS )N)�_events�_listen)r r r r r/ p s z_Dispatch._listenc C s | � | |�S )N)� __class__)r r" r r r r t s z_Dispatch._for_classc C s |j }| �|�S )N)r0 r )r �instancer" r r r � _for_instancew s z_Dispatch._for_instancec C s< d| j jkr0td| j j tfd| ji�}|| j _| �| |�S )z�Create a 'join' of this :class:`._Dispatch` and another. This new dispatcher will dispatch events to both :class:`._Dispatch` objects. �_joined_dispatch_clszJoined%s� __slots__)r0 r �typer �_JoinedDispatcherr+ r3 )r �otherr r r r �_join{ s z_Dispatch._joinc C s t � | jffS )N)r r )r r r r � __reduce__� s z_Dispatch.__reduce__Tc C s< x6|j D ],}t|t�rqt| |j��| �j||d� qW dS )zMPopulate from the listeners in another :class:`_Dispatch` object.)�only_propagateN)r& � isinstancer r, r � for_modify�_update)r r7 r: r! r r r r= � s z_Dispatch._updatec C s" x | j D ]}|�| ��� qW d S )N)r& r< �clear)r r! r r r �_clear� s z_Dispatch._clear)N)T)r r r r r4 �weakref�WeakKeyDictionaryr$ r( r* �propertyr& r/ r r2 r8 r9 r= r? r r r r r 3 s r c @ s e Zd ZdZdd� ZdS )� _EventMetazKIntercept new Event subclasses and create associated _Dispatch classes.c C s t | |||� t�| |||�S )N)�_create_dispatcher_classr5 r( )r � classname�bases�dict_r r r r( � s z_EventMeta.__init__N)r r r r r( r r r r rC � s rC c C s� t | d�r| jj}nt}dd� |D �}td| |fd|i�}||_| �| |�}x2|jD ](}t||t| || �� t | � | � qVW xP|j D ]F} t | t�r�| tk r�x.| j jjD ] } t|| j| � |j� | j� q�W q�W t| dd�r�t| �| j_dS )zRCreate a :class:`._Dispatch` class corresponding to an :class:`.Events` class.r c S s g | ]}t |�r|�qS r )r )r r- r r r � <listcomp>� s z,_create_dispatcher_class.<locals>.<listcomp>z %sDispatchr4 �_dispatch_targetN)�hasattrr r0 r r5 r+ � _set_dispatchr) r � _registrars�append� __bases__� issubclassr. r& r r, � dispatcherrI ) r rE rF rG Z dispatch_baseZ event_names� dispatch_clsZ dispatch_instr- Zsuper_r! r r r rD � s$ rD c C s2 x,| j jD ] }t| �| � t| s t|= q W d S )N)r r+ rL �remove)r r- r r r �_remove_dispatcher� s rS c @ sN e Zd ZdZedd� �Zedd� �Zeddd��Zed d � �Z ed d � �Z d S )�Eventsz>Define event listening functions for a particular target type.c C s |d �| _ | |_| j S )N)r r. )r rQ r r r rK � s zEvents._set_dispatchc sX � fdd�}� fdd�}t � d�rT|| jj�sP|t| jj�sP|t�rT|| jj�rT� S d S )Nc s t � fdd�| D ��S )Nc 3 s | ]}t � j|�V qd S )N)r; r )r �t)�targetr r � <genexpr>� s z;Events._accept_with.<locals>.dispatch_is.<locals>.<genexpr>)�all)�types)rV r r � dispatch_is� s z(Events._accept_with.<locals>.dispatch_isc s t � jj| �S )N)r; r r' )rU )rV r r �dispatch_parent_is� s z/Events._accept_with.<locals>.dispatch_parent_isr )rJ r r0 r5 r6 )r rV rZ r[ r )rV r � _accept_with� s zEvents._accept_withFc C s |j |||d� d S )N)� propagate�insert�named)Z base_listen)r � event_keyr] r^ r_ r r r r/ � s zEvents._listenc C s |� � d S )N)rR )r r` r r r �_remove� s zEvents._removec C s | j �� d S )N)r r? )r r r r r? � s z Events._clearN)FFF) r r r r � staticmethodrK � classmethodr\ r/ ra r? r r r r rT � s rT c @ s< e Zd ZdZdZdd� Zdd� Zedd� �Zed d � �Z d S ) r6 z5Represent a connection between two _Dispatch objects.)�localr' r c C s || _ || _| j j| _d S )N)rd r' r )r rd r' r r r r( s z_JoinedDispatcher.__init__c C s. t | j|�}t| j|j|�}t| |j|� |S )N)r, rd r r' r r) )r r r! Zjlr r r r* s z _JoinedDispatcher.__getattr__c C s | j jS )N)r' r/ )r r r r r/ s z_JoinedDispatcher._listenc C s | j jS )N)r' r. )r r r r r. s z_JoinedDispatcher._eventsN) r r r r r4 r( r* rB r/ r. r r r r r6 s r6 c @ s e Zd ZdZdd� Zdd� ZdS )rP z�Descriptor used by target classes to deliver the _Dispatch class at the class level and produce new _Dispatch instances for target instances. c C s |j | _ || _d S )N)r �events)r re r r r r( # s zdispatcher.__init__c C s( |d kr| j S | j �|� |jd< }|S )Nr )r r2 r )r �objr Zdispr r r �__get__' s zdispatcher.__get__N)r r r r r( rg r r r r rP s rP )r � __future__r r@ �attrr r r � r � defaultdict�listrL r �objectr r r5 rC rD rS �with_metaclassrT r6 rP r r r r �<module> s k "0