Source code for camelot.view.proxy.collection_proxy

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"""Proxy representing a collection of entities that live in the model thread.

The proxy represents them in the gui thread and provides access to the data
with zero delay.  If the data is not yet present in the proxy, dummy data is
returned and an update signal is emitted when the correct data is available.
"""

import logging
logger = logging.getLogger( 'camelot.view.proxy.collection_proxy' )

import datetime
import itertools

from PyQt4.QtCore import Qt, QThread
from PyQt4 import QtGui, QtCore

from camelot.core.utils import is_deleted
from camelot.core.files.storage import StoredFile
from camelot.view.art import Icon
from camelot.view.fifo import Fifo
from camelot.view.controls import delegates
from camelot.view.controls.exception import register_exception
from camelot.view.remote_signals import get_signal_handler
from camelot.view.model_thread import gui_function, \
                                      model_function, post

from camelot.core.files.storage import StoredImage

[docs]class ProxyDict(dict): """Subclass of dictionary to fool the QVariant object and prevent it from converting dictionary keys to whatever Qt object, but keep everything python""" pass
[docs]class DelayedProxy( object ): """A proxy object needs to be constructed within the GUI thread. Construct a delayed proxy when the construction of a proxy is needed within the Model thread. On first occasion the delayed proxy will be converted to a real proxy within the GUI thread """ @model_function def __init__( self, admin, collection_getter, columns_getter ): self._admin = admin self._collection_getter = collection_getter self._columns_getter = columns_getter @gui_function def __call__( self ): return CollectionProxy( self._admin, self._collection_getter, self._columns_getter ) def __unicode__(self): collection = self._collection_getter() if collection: try: return u','.join(list(unicode(o) or '' for o,_i in zip(collection, range(3)))) except TypeError, e: logger.error( 'could not convert object to unicode', exc_info=e ) return u''
@model_function
[docs]def strip_data_from_object( obj, columns ): """For every column in columns, get the corresponding value from the object. Getting a value from an object is time consuming, so using this function should be minimized. :param obj: the object of which to get data :param columns: a list of columns for which to get data """ row_data = [] def create_collection_getter( o, attr ): return lambda: getattr( o, attr ) for _i, col in enumerate( columns ): field_attributes = col[1] field_value = None try: getter = field_attributes['getter'] if field_attributes['python_type'] == list: field_value = DelayedProxy( field_attributes['admin'], create_collection_getter( obj, col[0] ), field_attributes['admin'].get_columns ) else: field_value = getter( obj ) except (Exception, RuntimeError, TypeError, NameError), e: logger.error('ProgrammingError : could not get field %s of object of type %s'%(col[0], obj.__class__.__name__), exc_info=e) finally: row_data.append( field_value ) return row_data
@model_function
[docs]def stripped_data_to_unicode( stripped_data, obj, static_field_attributes, dynamic_field_attributes ): """Extract for each field in the row data a 'visible' form of data""" row_data = [] for field_data, static_attributes, dynamic_attributes in zip( stripped_data, static_field_attributes, dynamic_field_attributes ): unicode_data = u'' choices = dynamic_attributes.get( 'choices', static_attributes.get('choices', None)) if 'unicode_format' in static_attributes: unicode_format = static_attributes['unicode_format'] if field_data != None: unicode_data = unicode_format( field_data ) elif choices: unicode_data = field_data for key, value in choices: if key == field_data: unicode_data = value elif isinstance( field_data, list ): unicode_data = u'.'.join( [unicode( e ) for e in field_data] ) elif isinstance( field_data, datetime.datetime ): # datetime should come before date since datetime is a subtype of date if field_data.year >= 1900: unicode_data = field_data.strftime( '%d/%m/%Y %H:%M' ) elif isinstance( field_data, datetime.date ): if field_data.year >= 1900: unicode_data = field_data.strftime( '%d/%m/%Y' ) elif isinstance( field_data, StoredImage): unicode_data = field_data.checkout_thumbnail(100, 100) elif field_data != None: unicode_data = unicode( field_data ) row_data.append( unicode_data ) return row_data
from camelot.view.proxy import ValueLoading
[docs]class EmptyRowData( object ): def __getitem__( self, column ): return ValueLoading
empty_row_data = EmptyRowData()
[docs]class SortingRowMapper( dict ): """Class mapping rows of a collection 1:1 without sorting and filtering, unless a mapping has been defined explicitly""" def __getitem__(self, row): try: return super(SortingRowMapper, self).__getitem__(row) except KeyError: return row
[docs]class CollectionProxy( QtCore.QAbstractTableModel ): """The CollectionProxy contains a limited copy of the data in the actual collection, usable for fast visualisation in a QTableView the CollectionProxy has some class attributes that can be overwritten when subclassing it : * header_icon : the icon to be used in the vertical header """ _header_font = QtGui.QApplication.font() _header_font_required = QtGui.QApplication.font() _header_font_required.setBold( True ) header_icon = Icon( 'tango/16x16/places/folder.png' ) item_delegate_changed_signal = QtCore.pyqtSignal() row_changed_signal = QtCore.pyqtSignal(int) exception_signal = QtCore.pyqtSignal(object) rows_removed_signal = QtCore.pyqtSignal() @gui_function def __init__( self, admin, collection_getter, columns_getter, max_number_of_rows = 10, edits = None, flush_changes = True, cache_collection_proxy = None ): """ :param admin: the admin interface for the items in the collection :param collection_getter: a function that takes no arguments and returns the collection that will be visualized. This function will be called inside the model thread, to prevent delays when this function causes the database to be hit. If the collection is a list, it should not contain any duplicate elements. :param columns_getter: a function that takes no arguments and returns the columns that will be cached in the proxy. This function will be called inside the model thread. :param cache_collection_proxy: the CollectionProxy on which this CollectionProxy will reuse the cache. Passing a cache has the advantage that objects that were present in the original cache will remain at the same row in the new cache This is used when a form is created from a tableview. Because between the last query of the tableview, and the first of the form, the object might have changed position in the query. """ super(CollectionProxy, self).__init__() from camelot.view.model_thread import get_model_thread self.logger = logging.getLogger(logger.name + '.%s'%id(self)) self.logger.debug('initialize query table for %s' % (admin.get_verbose_name())) self._mutex = QtCore.QMutex() self.admin = admin self._horizontal_header_height = QtGui.QFontMetrics( self._header_font_required ).height() + 10 vertical_header_font_height = QtGui.QFontMetrics( self._header_font ).height() self._vertical_header_height = vertical_header_font_height * self.admin.lines_per_row + 10 self.iconSize = QtCore.QSize( vertical_header_font_height, vertical_header_font_height ) if self.header_icon: self.form_icon = QtCore.QVariant( self.header_icon.getQIcon().pixmap( self.iconSize ) ) else: self.form_icon = QtCore.QVariant() self.validator = admin.create_validator( self ) self._collection_getter = collection_getter self.column_count = 0 self.flush_changes = flush_changes self.delegate_manager = None self.mt = get_model_thread() # Set database connection and load data self._rows = 0 self._columns = [] self._static_field_attributes = [] self._max_number_of_rows = max_number_of_rows if cache_collection_proxy: self.display_cache = cache_collection_proxy.display_cache.shallow_copy( 10 * self.max_number_of_rows ) self.edit_cache = cache_collection_proxy.edit_cache.shallow_copy( 10 * self.max_number_of_rows ) self.attributes_cache = cache_collection_proxy.attributes_cache.shallow_copy( 10 * self.max_number_of_rows ) else: self.display_cache = Fifo( 10 * self.max_number_of_rows ) self.edit_cache = Fifo( 10 * self.max_number_of_rows ) self.attributes_cache = Fifo( 10 * self.max_number_of_rows ) # The rows in the table for which a cache refill is under request self.rows_under_request = set() self._update_requests = list() # The rows that have unflushed changes self.unflushed_rows = set() self._sort_and_filter = SortingRowMapper() # Set edits self.edits = edits or [] self.row_changed_signal.connect( self._emit_changes ) self.rsh = get_signal_handler() self.rsh.connect_signals( self ) def get_columns(): self._columns = columns_getter() self._static_field_attributes = list(self.admin.get_static_field_attributes([c[0] for c in self._columns])) return self._columns post( get_columns, self.setColumns ) # # the initial collection might contain unflushed rows post( self._update_unflushed_rows ) # # in that way the number of rows is requested as well if cache_collection_proxy: self.setRowCount( cache_collection_proxy.rowCount() ) else: post( self.getRowCount, self.setRowCount ) self.logger.debug( 'initialization finished' ) @property
[docs] def max_number_of_rows(self): """The maximum number of rows to be displayed at once""" return self._max_number_of_rows
[docs] def get_validator(self): return self.validator
[docs] def map_to_source(self, sorted_row_number): """Converts a sorted row number to a row number of the source collection""" return self._sort_and_filter[sorted_row_number]
@model_function def _update_unflushed_rows( self ): """Verify all rows to see if some of them should be added to the unflushed rows""" for i, e in enumerate( self.get_collection() ): if hasattr(e, 'id') and not e.id: self.unflushed_rows.add( i )
[docs] def hasUnflushedRows( self ): """The model has rows that have not been flushed to the database yet, because the row is invalid """ has_unflushed_rows = ( len( self.unflushed_rows ) > 0 ) self.logger.debug( 'hasUnflushed rows : %s' % has_unflushed_rows ) return has_unflushed_rows
@model_function
[docs] def getRowCount( self ): # make sure we don't count an object twice if it is twice # in the list, since this will drive the cache nuts rows = len( set( self.get_collection() ) ) return rows
@gui_function
[docs] def revertRow( self, row ): def create_refresh_entity( row ): @model_function def refresh_entity(): o = self._get_object( row ) self.admin.refresh( o ) return row, o return refresh_entity post( create_refresh_entity( row ), self._revert_row )
@QtCore.pyqtSlot(tuple) @gui_function def _revert_row(self, row_and_entity ): row, entity = row_and_entity self.handleRowUpdate( row ) self.rsh.sendEntityUpdate( self, entity ) @gui_function
[docs] def refresh( self ): post( self.getRowCount, self._refresh_content )
@QtCore.pyqtSlot(int) @gui_function def _refresh_content(self, rows ): self.display_cache = Fifo( 10 * self.max_number_of_rows ) self.edit_cache = Fifo( 10 * self.max_number_of_rows ) self.attributes_cache = Fifo( 10 * self.max_number_of_rows ) locker = QtCore.QMutexLocker(self._mutex) self.rows_under_request = set() self.unflushed_rows = set() locker.unlock() self.setRowCount( rows )
[docs] def set_collection_getter( self, collection_getter ): self.logger.debug('set collection getter') self._collection_getter = collection_getter self.refresh()
@model_function
[docs] def get_collection( self ): return self._collection_getter()
@gui_function
[docs] def handleRowUpdate( self, row ): """Handles the update of a row when this row might be out of date""" self.display_cache.delete_by_row( row ) self.edit_cache.delete_by_row( row ) self.attributes_cache.delete_by_row( row ) self.dataChanged.emit( self.index( row, 0 ), self.index( row, self.column_count ) )
@QtCore.pyqtSlot( object, object )
[docs] def handle_entity_update( self, sender, entity ): """Handles the entity signal, indicating that the model is out of date""" self.logger.debug( '%s %s received entity update signal' % \ ( self.__class__.__name__, self.admin.get_verbose_name() ) ) if sender != self: try: row = self.display_cache.get_row_by_entity(entity) except KeyError: self.logger.debug( 'entity not in cache' ) return # # Because the entity is updated, it might no longer be in our # collection, therefore, make sure we don't access the collection # to strip data of the entity # def create_entity_update(row, entity): def entity_update(): columns = self.getColumns() self._add_data(columns, row, entity) return row return entity_update post(create_entity_update(row, entity), self._emit_changes) else: self.logger.debug( 'duplicate update' )
@QtCore.pyqtSlot( object, object )
[docs] def handle_entity_delete( self, sender, entity ): """Handles the entity signal, indicating that the model is out of date""" self.logger.debug( 'received entity delete signal' ) # # simply removing the entity from the collection might have # undesirable effects. eg when a form is pointing to this entity, # so instead update the entity # self.handle_entity_update( sender, entity )
@QtCore.pyqtSlot( object, object )
[docs] def handle_entity_create( self, sender, entity ): """Handles the entity signal, indicating that the model is out of date""" self.logger.debug( 'received entity create signal' ) # @todo : decide what to do when a new entity has been created, # probably do nothing return
@QtCore.pyqtSlot(int)
[docs] def setRowCount( self, rows ): """Callback method to set the number of rows @param rows the new number of rows """ self._rows = rows self.layoutChanged.emit()
[docs] def getItemDelegate( self ): """:return: a DelegateManager for this model, or None if no DelegateManager yet available a DelegateManager will be available once the item_delegate_changed signal has been emitted""" self.logger.debug( 'getItemDelegate' ) return self.delegate_manager
[docs] def getColumns( self ): """:return: the columns as set by the setColumns method""" return self._columns
@QtCore.pyqtSlot(object) @gui_function
[docs] def setColumns( self, columns ): """Callback method to set the columns :param columns: a list with fields to be displayed of the form [('field_name', field_attributes), ...] as returned by the getColumns method of the ElixirAdmin class """ self.logger.debug( 'setColumns' ) self.column_count = len( columns ) self._columns = columns delegate_manager = delegates.DelegateManager() delegate_manager.set_columns_desc( columns ) # set a delegate for the vertical header delegate_manager.insertColumnDelegate( -1, delegates.PlainTextDelegate(parent = delegate_manager) ) # # this loop can take a while to complete, so processEvents is called regulary # for i, c in enumerate( columns ): # if i%10==0: # QtCore.QCoreApplication.processEvents(QtCore.QEventLoop.ExcludeSocketNotifiers, 100) field_name = c[0] self.logger.debug( 'creating delegate for %s' % field_name ) if 'delegate' in c[1]: try: delegate = c[1]['delegate']( parent = delegate_manager, **c[1] ) except Exception, e: logger.error('ProgrammingError : could not create delegate for field %s'%field_name, exc_info=e) delegate = delegates.PlainTextDelegate( parent = delegate_manager, **c[1] ) delegate_manager.insertColumnDelegate( i, delegate ) continue elif c[1]['python_type'] == str: if c[1]['length']: delegate = delegates.PlainTextDelegate( parent = delegate_manager, maxlength = c[1]['length'] ) delegate_manager.insertColumnDelegate( i, delegate ) else: delegate = delegates.TextEditDelegate( parent = delegate_manager, **c[1] ) delegate_manager.insertColumnDelegate( i, delegate ) else: delegate = delegates.PlainTextDelegate(parent = delegate_manager) delegate_manager.insertColumnDelegate( i, delegate ) # Only set the delegate manager when it is fully set up self.delegate_manager = delegate_manager self.item_delegate_changed_signal.emit() self.layoutChanged.emit()
[docs] def rowCount( self, index = None ): return self._rows
[docs] def columnCount( self, index = None ): return self.column_count
@gui_function
[docs] def headerData( self, section, orientation, role ): """In case the columns have not been set yet, don't even try to get information out of them """ if orientation == Qt.Horizontal: if section >= self.column_count: return QtCore.QAbstractTableModel.headerData( self, section, orientation, role ) c = self.getColumns()[section] if role == Qt.DisplayRole: return QtCore.QVariant( unicode(c[1]['name']) ) elif role == Qt.FontRole: if ( 'nullable' in c[1] ) and \ ( c[1]['nullable'] == False ): return QtCore.QVariant( self._header_font_required ) else: return QtCore.QVariant( self._header_font ) elif role == Qt.SizeHintRole: option = QtGui.QStyleOptionViewItem() if self.delegate_manager: editor_size = self.delegate_manager.sizeHint( option, self.index( 0, section ) ) else: editor_size = QtCore.QSize(0, 0) if 'minimal_column_width' in c[1]: minimal_column_width = QtGui.QFontMetrics( self._header_font ).size( Qt.TextSingleLine, 'A' ).width()*c[1]['minimal_column_width'] else: minimal_column_width = 100 editable = True if 'editable' in c[1]: editable = c[1]['editable'] label_size = QtGui.QFontMetrics( self._header_font_required ).size( Qt.TextSingleLine, unicode(c[1]['name']) + ' ' ) size = max( minimal_column_width, label_size.width() + 10 ) if editable: size = max( size, editor_size.width() ) return QtCore.QVariant( QtCore.QSize( size, self._horizontal_header_height ) ) else: if role == Qt.SizeHintRole: if self.header_icon: return QtCore.QVariant( QtCore.QSize( self.iconSize.width() + 10, self._vertical_header_height ) ) else: # if there is no icon, the line numbers will be displayed, so create some space for those return QtCore.QVariant( QtCore.QSize( QtGui.QFontMetrics( self._header_font ).size( Qt.TextSingleLine, str(self._rows) ).width() + 10, self._vertical_header_height ) ) if role == Qt.DecorationRole: return self.form_icon # elif role == Qt.DisplayRole: # return QtCore.QVariant() return QtCore.QAbstractTableModel.headerData( self, section, orientation, role )
@gui_function
[docs] def sort( self, column, order ): """reimplementation of the QAbstractItemModel its sort function""" def create_sort(column, order): def sort(): unsorted_collection = [(i,o) for i,o in enumerate(self.get_collection())] key = lambda item:getattr(item[1], self._columns[column][0]) unsorted_collection.sort(key=key, reverse=order) for j,(i,_o) in enumerate(unsorted_collection): self._sort_and_filter[j] = i return len(unsorted_collection) return sort post(create_sort(column, order), self._refresh_content)
@gui_function
[docs] def data( self, index, role ): """:return: the data at index for the specified role This function will return ValueLoading when the data has not yet been fetched from the underlying model. It will then send a request to the model thread to fetch this data. Once the data is readily available, the dataChanged signal will be emitted Using Qt.UserRole as a role will return all the field attributes of the index. Using Qt.UserRole+1 will return the object of which an attribute is displayed in that specific cell """ if not index.isValid() or \ not ( 0 <= index.row() <= self.rowCount( index ) ) or \ not ( 0 <= index.column() <= self.columnCount( index ) ): return QtCore.QVariant() if role in (Qt.EditRole, Qt.DisplayRole): if role == Qt.EditRole: cache = self.edit_cache else: cache = self.display_cache data = self._get_row_data( index.row(), cache ) value = data[index.column()] if isinstance( value, DelayedProxy ): value = value() # store the created proxy, to prevent recreation of it # afterwards. data[index.column()] = value if isinstance( value, datetime.datetime ): # Putting a python datetime into a QVariant and returning # it to a PyObject seems to be buggy, therefore we chop the # microseconds if value: value = QtCore.QDateTime(value.year, value.month, value.day, value.hour, value.minute, value.second) return QtCore.QVariant( value ) elif role == Qt.ToolTipRole: return QtCore.QVariant(self._get_field_attribute_value(index, 'tooltip')) elif role == Qt.BackgroundRole: return QtCore.QVariant(self._get_field_attribute_value(index, 'background_color') or QtGui.QColor('White')) elif role == Qt.UserRole: field_attributes = ProxyDict(self._static_field_attributes[index.column()]) dynamic_field_attributes = self._get_row_data( index.row(), self.attributes_cache )[index.column()] if dynamic_field_attributes != ValueLoading: field_attributes.update( dynamic_field_attributes ) return QtCore.QVariant(field_attributes) elif role == Qt.UserRole + 1: try: return QtCore.QVariant( self.edit_cache.get_entity_at_row( index.row() ) ) except KeyError: return QtCore.QVariant( ValueLoading ) return QtCore.QVariant()
def _get_field_attribute_value(self, index, field_attribute): """Get the values for the static and the dynamic field attributes at once :return: the value of the field attribute""" try: return self._static_field_attributes[index.column()][field_attribute] except KeyError: value = self._get_row_data( index.row(), self.attributes_cache )[index.column()] if value == ValueLoading: return None return value.get(field_attribute, None) @model_function def _handle_update_requests(self): # # Copy the update requests and clear the list of requests # locker = QtCore.QMutexLocker(self._mutex) update_requests = [u for u in self._update_requests] self._update_requests = [] locker.unlock() # # Handle the requests # return_list = [] for flushed, row, column, value in update_requests: attribute, field_attributes = self.getColumns()[column] from sqlalchemy.exc import DatabaseError from sqlalchemy import orm new_value = value() self.logger.debug( 'set data for row %s;col %s' % ( row, column ) ) if new_value == ValueLoading: return None # # don't use _get_object, but only update objects which are in the # cache, otherwise it is not sure that the object updated is the # one that was edited # o = self.edit_cache.get_entity_at_row( row ) if not o: # the object might have been deleted from the collection while the editor # was still open self.logger.debug( 'this object is no longer in the collection' ) try: self.unflushed_rows.remove( row ) except KeyError: pass return # # the object might have been deleted while an editor was open # if self.admin.is_deleted( o ): return old_value = getattr( o, attribute ) # # When the value is a related object, the related object might have changed # changed = ( new_value != old_value ) or ( field_attributes.get('embedded', False) and \ field_attributes.get('target', False)) # # In case the attribute is a OneToMany or ManyToMany, we cannot simply compare the # old and new value to know if the object was changed, so we'll # consider it changed anyway # direction = field_attributes.get( 'direction', None ) if direction in ( orm.interfaces.MANYTOMANY, orm.interfaces.ONETOMANY ): changed = True if changed: # update the model model_updated = False try: setattr( o, attribute, new_value ) # # setting this attribute, might trigger a default function to return a value, # that was not returned before # self.admin.set_defaults( o, include_nullable_fields=False ) model_updated = True except AttributeError, e: self.logger.error( u"Can't set attribute %s to %s" % ( attribute, unicode( new_value ) ), exc_info = e ) except TypeError: # type error can be raised in case we try to set to a collection pass if self.flush_changes and self.validator.isValid( row ): # save the state before the update try: self.admin.flush( o ) except DatabaseError, e: #@todo: when flushing fails, the object should not be removed from the unflushed rows ?? self.logger.error( 'Programming Error, could not flush object', exc_info = e ) locker.relock() try: self.unflushed_rows.remove( row ) except KeyError: pass locker.unlock() # # we can only track history if the model was updated, and it was # flushed before, otherwise it has no primary key yet # if model_updated and hasattr(o, 'id') and o.id: # # in case of files or relations, we cannot pickle them # if isinstance( old_value, StoredFile ): old_value = old_value.name if not direction: from camelot.model.memento import BeforeUpdate # only register the update when the camelot model is active if hasattr(BeforeUpdate, 'query'): from camelot.model.authentication import getCurrentAuthentication history = BeforeUpdate( model = unicode( self.admin.entity.__name__ ), primary_key = o.id, previous_attributes = {attribute:old_value}, authentication = getCurrentAuthentication() ) try: history.flush() except DatabaseError, e: self.logger.error( 'Programming Error, could not flush history', exc_info = e ) # update the cache self._add_data(self.getColumns(), row, o) #@todo: update should only be sent remotely when flush was done self.rsh.sendEntityUpdate( self, o ) for depending_obj in self.admin.get_depending_objects( o ): self.rsh.sendEntityUpdate( self, depending_obj ) return_list.append(( ( row, 0 ), ( row, len( self.getColumns() ) ) )) elif flushed: locker.relock() self.logger.debug( 'old value equals new value, no need to flush this object' ) try: self.unflushed_rows.remove( row ) except KeyError: pass locker.unlock() return return_list
[docs] def setData( self, index, value, role = Qt.EditRole ): """Value should be a function taking no arguments that returns the data to be set This function will then be called in the model_thread """ # # prevent data of being set in rows not actually in this model # if not index.isValid(): return False if role == Qt.EditRole: # if the field is not editable, don't waste any time and get out of here # editable should be explicitely True, since the _get_field_attribute_value # might return intermediary values such as ValueLoading ?? if self._get_field_attribute_value(index, 'editable') != True: return locker = QtCore.QMutexLocker( self._mutex ) flushed = ( index.row() not in self.unflushed_rows ) self.unflushed_rows.add( index.row() ) self._update_requests.append( (flushed, index.row(), index.column(), value) ) locker.unlock() post( self._handle_update_requests ) return True
@QtCore.pyqtSlot(int) @gui_function def _emit_changes( self, row ): if row!=None: self.dataChanged.emit( self.index( row, 0 ), self.index( row, self.column_count ) )
[docs] def flags( self, index ): """Returns the item flags for the given index""" flags = Qt.ItemIsEnabled | Qt.ItemIsSelectable if self._get_field_attribute_value(index, 'editable'): flags = flags | Qt.ItemIsEditable return flags
def _add_data(self, columns, row, obj): """Add data from object o at a row in the cache :param columns: the columns of which to strip data :param row: the row in the cache into which to add data :param obj: the object from which to strip the data """ if not self.admin.is_deleted( obj ): row_data = strip_data_from_object( obj, columns ) dynamic_field_attributes = list(self.admin.get_dynamic_field_attributes( obj, (c[0] for c in columns))) static_field_attributes = self.admin.get_static_field_attributes( (c[0] for c in columns) ) unicode_row_data = stripped_data_to_unicode( row_data, obj, static_field_attributes, dynamic_field_attributes ) else: row_data = [None] * len(columns) dynamic_field_attributes = [{'editable':False}] * len(columns) static_field_attributes = self.admin.get_static_field_attributes( (c[0] for c in columns) ) unicode_row_data = [u''] * len(columns) locker = QtCore.QMutexLocker( self._mutex ) self.edit_cache.add_data( row, obj, row_data ) self.display_cache.add_data( row, obj, unicode_row_data ) self.attributes_cache.add_data(row, obj, dynamic_field_attributes ) locker.unlock() # # it might be that the CollectionProxy is deleted on the QT side of # the application # if not is_deleted( self ): self.row_changed_signal.emit( row ) def _skip_row(self, row, obj): """:return: True if the object obj is already in the cache, but at a different row then row. If this is the case, this object should not be put in the cache at row, and this row should be skipped alltogether. """ try: return self.edit_cache.get_row_by_entity(obj)!=row except KeyError: pass return False def _offset_and_limit_rows_to_get( self ): """From the current set of rows to get, find the first continuous range of rows that should be fetched. :return: (offset, limit) """ offset, limit, previous_length, i = 0, 0, 0, 0 # # wait for a while until the rows under request don't change any # more # locker = QtCore.QMutexLocker(self._mutex) while previous_length != len(self.rows_under_request): previous_length = len(self.rows_under_request) locker.unlock() QThread.msleep(5) locker.relock() # # now filter out all rows that have been put in the cache # the gui thread didn't know about # rows_to_get = self.rows_under_request rows_already_there = set() for row in rows_to_get: if self.edit_cache.has_data_at_row(row): rows_already_there.add(row) rows_to_get.difference_update( rows_already_there ) # # see if there is anything left to do # try: if rows_to_get: rows_to_get = list(rows_to_get) locker.unlock() rows_to_get.sort() offset = rows_to_get[0] # # find first discontinuity # for i in range(offset, rows_to_get[-1]+1): if rows_to_get[i-offset] != i: break limit = i - offset + 1 except IndexError, e: logger.error('index error with rows_to_get %s'%unicode(rows_to_get), exc_info=e) raise e return (offset, limit) @model_function def _extend_cache( self ): """Extend the cache around the rows under request""" offset, limit = self._offset_and_limit_rows_to_get() if limit: columns = self.getColumns() collection = self.get_collection() skipped_rows = 0 for i in range(offset, min(offset + limit + 1, self._rows)): object_found = False while not object_found: unsorted_row = self._sort_and_filter[i] obj = collection[unsorted_row+skipped_rows] if self._skip_row(i, obj): skipped_rows = skipped_rows + 1 else: self._add_data(columns, i, obj) object_found = True return ( offset, limit ) @model_function def _get_object( self, sorted_row_number ): """Get the object corresponding to row :return: the object at row row or None if the row index is invalid """ try: # first try to get the primary key out of the cache, if it's not # there, query the collection_getter return self.edit_cache.get_entity_at_row( sorted_row_number ) except KeyError: pass try: return self.get_collection()[self.map_to_source(sorted_row_number)] except IndexError: pass return None @QtCore.pyqtSlot(tuple) def _cache_extended( self, interval ): offset, limit = interval locker = QtCore.QMutexLocker(self._mutex) self.rows_under_request.difference_update( set( range( offset, offset + limit + 1) ) ) locker.unlock() def _get_row_data( self, row, cache ): """Get the data which is to be visualized at a certain row of the table, if needed, post a refill request the cache to get the object and its neighbours in the cache, meanwhile, return an empty object :param row: the row of the table for which to get the data :param cache: the cache out of which to get row data :return: row_data """ try: data = cache.get_data_at_row( row ) # # check if data is None, then the cache was a copy of previous # cache, and the data should be refetched # if data is None: raise KeyError return data except KeyError: if row not in self.rows_under_request: locker = QtCore.QMutexLocker(self._mutex) self.rows_under_request.add( row ) locker.unlock() post( self._extend_cache, self._cache_extended ) return empty_row_data @model_function
[docs] def remove( self, o ): collection = self.get_collection() if o in collection: collection.remove( o ) self._rows -= 1
@model_function
[docs] def append( self, o ): collection = self.get_collection() if o not in collection: collection.append( o )
@model_function
[docs] def remove_objects( self, objects_to_remove, delete = True ): """ :param objects_to_remove: a list of objects that need to be removed from the collection :param delete: True if the objects need to be deleted """ # # it might be impossible to determine the depending objects once # the object has been removed from the collection # depending_objects = set( itertools.chain.from_iterable( self.admin.get_depending_objects( o ) for o in objects_to_remove ) ) for obj in objects_to_remove: # # We should not update depending objects that have # been deleted themselves # if delete: try: depending_objects.remove( obj ) except KeyError: pass # # if needed, delete the objects # if delete: self.rsh.sendEntityDelete( self, obj ) self.admin.delete( obj ) # remove only when delete took place without exception self.remove( obj ) else: # even if the object is not deleted, it needs to be flushed to make # sure the persisted object is out of the collection as well self.remove( obj ) if self.admin.is_persistent( obj ): self.admin.flush( obj ) # # remove the entity from the cache, only if the delete and remove # took place without exception # self.display_cache.delete_by_entity( obj ) self.attributes_cache.delete_by_entity( obj ) self.edit_cache.delete_by_entity( obj ) for depending_obj in depending_objects: self.rsh.sendEntityUpdate( self, depending_obj ) post( self.getRowCount, self._refresh_content )
@gui_function
[docs] def remove_rows( self, rows, delete = True ): """Remove the entity associated with this row from this collection @param rows: a list with the numbers of the rows to remove @param delete: delete the entity as well The rows_removed signal will be emitted when the removal was successful, otherwise the exception_signal will be emitted. """ self.logger.debug( 'remove rows' ) def create_delete_function( rows ): def delete_function(): """Remove all rows from the underlying collection :return: the number of rows left in the collection""" try: objects_to_remove = [self._get_object( row ) for row in rows] self.remove_objects( objects_to_remove, delete ) self.rows_removed_signal.emit() except Exception, exc: exc_info = register_exception( logger, 'exception while removing rows', exc ) self.exception_signal.emit( exc_info ) return delete_function post( create_delete_function(rows) ) return True
@gui_function
[docs] def copy_row( self, row ): """Copy the entity associated with this row to the end of the collection :param row: the row number """ def create_copy_function( row ): def copy_function(): o = self._get_object(row) new_object = self.admin.copy( o ) self.append_object(new_object) return copy_function post( create_copy_function( row ) ) return True
@model_function
[docs] def append_object( self, obj ): """Append an object to this collection, set the possible defaults and flush the object if possible/needed :param obj: the object to be added to the collection :return: the new number of rows in the collection """ rows = self.rowCount() row = max( rows - 1, 0 ) self.beginInsertRows( QtCore.QModelIndex(), row, row ) self.append( obj ) # defaults might depend on object being part of a collection self.admin.set_defaults( obj ) self.unflushed_rows.add( row ) if self.flush_changes and not len( self.validator.objectValidity( obj ) ): self.admin.flush( obj ) try: self.unflushed_rows.remove( row ) except KeyError: pass for depending_obj in self.admin.get_depending_objects( obj ): self.rsh.sendEntityUpdate( self, depending_obj ) # TODO : it's not because an object is added to this list, that it was created # it might as well exist already, eg. manytomany relation # from camelot.model.memento import Create # from camelot.model.authentication import getCurrentAuthentication # history = Create(model=unicode(self.admin.entity.__name__), # primary_key=o.id, # authentication = getCurrentAuthentication()) # elixir.session.flush([history]) # self.rsh.sendEntityCreate(self, o) self._rows = rows + 1 self.endInsertRows() return self._rows
@QtCore.pyqtSlot(object) @gui_function
[docs] def append_row( self, object_getter ): """ :param object_getter: a function that returns the object to be put in the appended row. """ def create_append_function( getter ): def append_function(): return self.append_object( getter() ) return append_function post( create_append_function( object_getter ), self._refresh_content )
@model_function
[docs] def getData( self ): """Generator for all the data queried by this proxy""" for _i, o in enumerate( self.get_collection() ): yield strip_data_from_object( o, self.getColumns() )
[docs] def get_admin( self ): """Get the admin object associated with this model""" return self.admin

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