boinc/py/Boinc/boincxml.py

147 lines
4.8 KiB
Python

#!/usr/bin/env python
# $Id$
# boincxml.py - xml utilities for boinc
import sys
import xml.dom.minidom
def append_new_element(parent_node, name):
new_element = xml.dom.minidom.Element(name)
if isinstance(parent_node,xml.dom.minidom.Document):
new_element.ownerDocument = parent_node
else:
assert(parent_node.ownerDocument)
new_element.ownerDocument = parent_node.ownerDocument
parent_node.appendChild(new_element)
return new_element
def get_elements(node, name):
return node.getElementsByTagName(name)
def get_element(node, name, optional=True):
try:
return get_elements(node,name)[0]
except IndexError:
if optional:
return append_new_element(node, name)
raise SystemExit("ERROR: Couldn't find xml node <%s>"% name)
def _None2Str(object):
if object == None:
return ''
else:
return object
def get_element_data(node):
return node and _None2Str(node.firstChild and node.firstChild.data)
def get_element_int(node, default=0):
try:
return int(get_element_data(node))
except:
return default
def get_child_elements(node):
return filter(lambda node: node.nodeType == node.ELEMENT_NODE, node.childNodes)
def set_element(node, new_data):
if node.firstChild and node.firstChild.data:
node.firstChild.data = str(new_data)
else:
# different versions of pyxml have different interface (!)
try:
new_data_node = xml.dom.minidom.Text()
except:
new_data_node = xml.dom.minidom.Text('')
new_data_node.data = str(new_data)
new_data_node.ownerDocument = node.ownerDocument
node.appendChild(new_data_node)
def strip_white_space(node):
''' strip white space from text nodes, and remove empty nodes. '''
# the [:] below is to copy the list since removing children modifies the
# list.
for child in node.childNodes[:]:
if child.nodeType == child.TEXT_NODE:
child.data = child.data.strip()
if not child.data:# and (child.nextSibling or child.previousSibling):
node.removeChild(child)
else:
strip_white_space(child)
def get_elements_as_dict(node):
dict = {}
for child in get_child_elements(node):
# note: str() changes from unicode to single-byte strings
dict[str(child.nodeName)] = get_element_data(child)
return dict
class ConfigDict:
def __init__(self, dom_node):
self._node = dom_node
self._name = self._node.nodeName
self.__dict__.update(get_elements_as_dict(self._node))
def save(self):
for key in self.__dict__:
if key.startswith('_'): continue
set_element( get_element(self._node,key,1), str(self.__dict__[key]) )
def debug_print(self):
for key in self.__dict__.keys():
print key.rjust(15), '=', self.__dict__[key]
class ConfigDictList(list):
def __init__(self, dom_node, item_class=ConfigDict):
self._node = dom_node
list.__init__(self, map(item_class, get_child_elements(self._node)))
def save(self):
map(ConfigDict.save, self)
def make_node_and_append(self, name):
'''Make a new ConfigDict and append it. Returns new ConfigDict.'''
new_element = append_new_element(self._node, name)
new_cd = ConfigDict(new_element)
self.append(new_cd)
return new_cd
def remove_node(self, item):
self.remove(item)
self._node.removeChild(item._node)
class XMLConfig:
'''Base class for xml config files'''
def __init__(self, filename = None):
# default_filename should be defined by children
self.filename = filename or self.default_filename
def _init_empty_xml(self):
self.xml = xml.dom.minidom.parseString(self.default_xml)
def init_empty(self):
self._init_empty_xml()
self._get_elements()
return self
def read(self, failopen_ok=False):
"""Read the XML object's file source and return self."""
try:
self.xml = xml.dom.minidom.parse(self.filename)
strip_white_space(self.xml)
except IOError, e:
if not failopen_ok:
# raise
raise Exception("%s: Couldn't parse XML config\n%s: %s"%(sys.argv[0],sys.argv[0],e))
print >>sys.stderr, "Warning:", e
# self.xml = xml.dom.minidom.Document()
self._init_empty_xml()
self._get_elements()
return self
def _get_elements(self):
pass
def write(self, output=None):
"""Write XML data to filename, or other stream."""
self._set_elements()
if not output:
output = open(self.filename,'w')
self.xml.writexml(output, "", " ", "\n")
print >>output
return self
def _set_elements(self):
pass