Python读取与更改xml文件

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原始文档内容

<?xml version=”1.0″ encoding=”UTF-8″?>

<framework>

<processers>

<processer name=”AProcesser” file=”lib64/A.so”

path=”/tmp”>

</processer>

<processer name=”BProcesser” file=”lib64/B.so” value=”fordelete”>

</processer>

<processer name=”BProcesser” file=”lib64/B.so2222222″/>

<services>

<service name=”search” prefix=”/bin/search?”

output_formatter=”OutPutFormatter:service_inc”>

<chain sequency=”chain1″/>

<chain sequency=”chain2″></chain>

</service>

<service name=”update” prefix=”/bin/update?”>

<chain sequency=”chain3″ value=”fordelete”/>

</service>

</services>

</processers>

</framework>

”’

from xml.etree.ElementTree import ElementTree,Element

def read_xml(in_path):

””’读取并解析xml文件

in_path: xml路径

return: ElementTree”’

tree = ElementTree()

tree.parse(in_path)

return tree

def write_xml(tree, out_path):

””’将xml文件写出

tree: xml树

out_path: 写出路径”’

tree.write(out_path, encoding=”utf-8″,xml_declaration=True)

def if_match(node, kv_map):

””’判断某个节点是否包含所有传入参数属性

node: 节点

kv_map: 属性及属性值组成的map”’

for key in kv_map:

if node.get(key) != kv_map.get(key):

return False

return True

#—————search —–

def find_nodes(tree, path):

””’查找某个路径匹配的所有节点

tree: xml树

path: 节点路径”’

return tree.findall(path)

def get_node_by_keyvalue(nodelist, kv_map):

””’根据属性及属性值定位符合的节点，返回节点

nodelist: 节点列表

kv_map: 匹配属性及属性值map”’

result_nodes = []

for node in nodelist:

if if_match(node, kv_map):

result_nodes.append(node)

return result_nodes

#—————change —–

def change_node_properties(nodelist, kv_map, is_delete=False):

””’修改/增加 /删除 节点的属性及属性值

nodelist: 节点列表

kv_map:属性及属性值map”’

for node in nodelist:

for key in kv_map:

if is_delete:

if key in node.attrib:

del node.attrib[key]

else:

node.set(key, kv_map.get(key))

def change_node_text(nodelist, text, is_add=False, is_delete=False):

””’改变/增加/删除一个节点的文本

nodelist:节点列表

text : 更新后的文本”’

for node in nodelist:

if is_add:

node.text += text

elif is_delete:

node.text = “”

else:

node.text = text

def create_node(tag, property_map, content):

””’新造一个节点

tag:节点标签

property_map:属性及属性值map

content: 节点闭合标签里的文本内容

return 新节点”’

element = Element(tag, property_map)

element.text = content

return element

def add_child_node(nodelist, element):

””’给一个节点添加子节点

nodelist: 节点列表

element: 子节点”’

for node in nodelist:

node.append(element)

def del_node_by_tagkeyvalue(nodelist, tag, kv_map):

””’同过属性及属性值定位一个节点，并删除之

nodelist: 父节点列表

tag:子节点标签

kv_map: 属性及属性值列表”’

for parent_node in nodelist:

children = parent_node.getchildren()

for child in children:

if child.tag == tag and if_match(child, kv_map):

parent_node.remove(child)

if __name__ == “__main__”:

#1. 读取xml文件

tree = read_xml(“D://dd.xml”)

#2. 属性修改

#A. 找到父节点

nodes = find_nodes(tree, “processers/processer”)

#B. 通过属性准确定位子节点

result_nodes = get_node_by_keyvalue(nodes, {“name”:”BProcesser”})

#C. 修改节点属性

change_node_properties(result_nodes, {“age”: “1”})

#D. 删除节点属性

change_node_properties(result_nodes, {“value”:””}, True)

#3. 节点修改

#A.新建节点

a = create_node(“person”, {“age”:”15″,”money”:”200000″}, “this is the firest content”)

#B.插入到父节点之下

add_child_node(result_nodes, a)

#4. 删除节点

#定位父节点

del_parent_nodes = find_nodes(tree, “processers/services/service”)

#准确定位子节点并删除之

target_del_node = del_node_by_tagkeyvalue(del_parent_nodes, “chain”, {“sequency” : “chain1”})

#5. 修改节点文本

#定位节点

text_nodes = get_node_by_keyvalue(find_nodes(tree, “processers/services/service/chain”), {“sequency”:”chain3″})

change_node_text(text_nodes, “new text”)

#6. 输出到结果文件

write_xml(tree, “D://xiugai.xml”)

”’

更改之后的内容

<?xml version=’1.0′ encoding=’utf-8′?>

<framework>

<processers>

<processer file=”lib64/A.so” name=”AProcesser” path=”/tmp”>

</processer>

<processer age=”1″ file=”lib64/B.so” name=”BProcesser”>

<person age=”15″ money=”200000″>this is the firest content</person></processer>

<processer age=”1″ file=”lib64/B.so2222222″ name=”BProcesser”><person age=”15″ money=”200000″>this is the firest content</person></processer>

<services>

<service name=”search” output_formatter=”OutPutFormatter:service_inc” prefix=”/bin/search?”>

<chain sequency=”chain2″ />

</service>

<service name=”update” prefix=”/bin/update?”>

<chain sequency=”chain3″ value=”fordelete”>new text</chain>

</service>

</services>

</processers>

</framework>

”’