# Name: attribute.py
# Purpose: Attribute classes
# Author: Roman Rolinsky <rolinsky@femagsoft.com>
# Created: 25.06.2007
# RCS-ID: $Id$
'''
Attribute processing classes.
This module contains some predefined classes which can be used to store and
retrieve XML data into Python objects.
'''
import cPickle
from model import Model
class Attribute:
'''Base class, used for simple attributes, i.e. single attributes
storing data as text strings.'''
@staticmethod
def add(parentNode, attribute, value):
'''Store attribute value in DOM as a text node.
@param attribute: Attribute name.
@param value: Attribute value (Python string).
'''
if attribute == '':
elem = parentNode
else:
elem = Model.dom.createElement(attribute)
parentNode.appendChild(elem)
text = Model.dom.createTextNode(value)
elem.appendChild(text)
@staticmethod
def get(node):
'''Get value (or return a default value) from a DOM C{Element} object.'''
if node is None: return ''
try:
n = node.childNodes[0]
return n.wholeText
except IndexError:
return ''
class ContentAttribute:
'''Content attribute class. Value is a list of strings.'''
@staticmethod
def add(parentNode, attribute, value):
contentElem = Model.dom.createElement(attribute)
parentNode.appendChild(contentElem)
for item in value:
elem = Model.dom.createElement('item')
text = Model.dom.createTextNode(item)
elem.appendChild(text)
contentElem.appendChild(elem)
@staticmethod
def get(node):
if node is None: return []
value = []
for n in node.childNodes:
if n.nodeType == node.ELEMENT_NODE and n.tagName == 'item':
value.append(Attribute.get(n))
return value
class CheckContentAttribute:
'''CheckList content. Value is a list of tuples (checked, string).'''
@staticmethod
def add(parentNode, attribute, value):
contentElem = Model.dom.createElement(attribute)
parentNode.appendChild(contentElem)
for checked,item in value:
elem = Model.dom.createElement('item')
if checked:
elem.setAttribute('checked', '1')
text = Model.dom.createTextNode(item)
elem.appendChild(text)
contentElem.appendChild(elem)
@staticmethod
def get(node):
if node is None: return []
value = []
for n in node.childNodes:
if n.nodeType == node.ELEMENT_NODE and n.tagName == 'item':
checked = bool(n.getAttribute('checked'))
value.append((checked, Attribute.get(n)))
return value
class DictAttribute:
'''DictAttribute uses dictionary object for passing data.'''
attributes = []
@classmethod
def add(cls, parentNode, attribute, value):
fontElem = Model.dom.createElement(attribute)
parentNode.appendChild(fontElem)
for a in filter(value.has_key, cls.attributes):
elem = Model.dom.createElement(a)
text = Model.dom.createTextNode(value[a])
elem.appendChild(text)
fontElem.appendChild(elem)
@staticmethod
def get(node):
if node is None: return {}
value = {}
for n in node.childNodes:
if n.nodeType == node.ELEMENT_NODE:
value[n.tagName] = Attribute.get(n)
return value
class FontAttribute(DictAttribute):
attributes = ['size', 'style', 'weight', 'underlined', 'family', 'face', 'encoding',
'sysfont', 'relativesize']
class CodeAttribute(DictAttribute):
attributes = ['events', 'assign_var']
class MultiAttribute:
'''Repeated attribute like growablecols.'''
@staticmethod
def add(parentNode, attribute, value):
for v in value:
elem = Model.dom.createElement(attribute)
parentNode.appendChild(elem)
text = Model.dom.createTextNode(v)
elem.appendChild(text)
@staticmethod
def get(node):
if node is None: return []
tag = node.tagName # remember tag name
value = []
# Look for multiple tags
while node:
if node.nodeType == node.ELEMENT_NODE and node.tagName == tag:
value.append(Attribute.get(node))
node = node.nextSibling
return value
class BitmapAttribute:
'''Bitmap attribute.'''
@staticmethod
def add(parentNode, attribute, value):
if not value[0] and not value[1]: return
if attribute == 'object':
elem = parentNode
else:
elem = Model.dom.createElement(attribute)
parentNode.appendChild(elem)
if value[0]:
elem.setAttribute('stock_id', value[0])
else:
if elem.hasAttribute('stock_id'): elem.removeAttribute('stock_id')
text = Model.dom.createTextNode(value[1])
elem.appendChild(text)
@staticmethod
def get(node):
if node is None: return []
return [node.getAttribute('stock_id'), Attribute.get(node)]
class AttributeAttribute:
'''Attribute as an XML attribute of the element node.'''
@staticmethod
def add(elem, attribute, value):
if value:
elem.setAttribute(attribute, value)
else:
if elem.hasAttribute(attribute): elem.removeAttribute(attribute)
@staticmethod
def getAA(elem, attribute):
return elem.getAttribute(attribute)
class EncodingAttribute(AttributeAttribute):
'''Encoding is a special attribute stored in dom object.'''
@staticmethod
def add(elem, attribute, value):
Model.dom.encoding = value
@staticmethod
def getAA(elem, attribute):
return Model.dom.encoding
class CDATAAttribute(Attribute):
def add(parentNode, attribute, value):
'''value is a dictionary.'''
if value:
elem = Model.dom.createElement(attribute)
parentNode.appendChild(elem)
data = Model.dom.createCDATASection(cPickle.dumps(value))
elem.appendChild(data)
@staticmethod
def get(node):
'''Get XRCED data from a CDATA text node.'''
try:
n = node.childNodes[0]
if n.nodeType == n.CDATA_SECTION_NODE:
return cPickle.loads(n.wholeText.encode())
except IndexError:
pass
class CommentAttribute(AttributeAttribute):
'''Comment is the value of comment object.'''
@staticmethod
def add(node, attribute, value):
node.data = value
@staticmethod
def getAA(node, attribute):
return node.data
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