Python 解析 xml文档

最近遇到需要使用脚本语言解析XML文档的问题，在shell和Python之间纠结半天，发现还是Python中现成的类库好用。

如下是需要解析的xml文档Guest.xml：        

<?xml version="1.0" encoding="UTF-8" ?>
<customer name="useX" id="111111111" mail="[email protected]">
    <orderID id="0123456789">2015-05-22</orderID>
    <platform id="0001">MSD638</platform>
    <modules>
        <module id="1000001">
            <modulename>Tuner</modulename>
            <type>23</type>
        </module>
        <module id="1000002">
            <modulename>Ircode</modulename>
            <type>22</type>
        </module>
        <module id="1000003">
            <modulename>Logo</modulename>
            <type>27</type>
        </module>
        <module id="1000004">
            <modulename>Backlight</modulename>
            <type>25</type>
        </module>
        <module id="1000005">
            <modulename>Panel</modulename>
            <type>20</type>
        </module>
        <module id="1000006">
            <modulename>Board</modulename>
            <type>23</type>
        </module>
    </modules>
</customer>

下面是解析使用的Python脚本parseGuestXML.py：

#!/usr/bin/python
# -*- coding:utf-8 -*-
"""
Build image output_image_file from input_directory and properties_file.

Usage:  build_image input_directory properties_file output_image_file

"""

from  xml.dom import  minidom
def get_attrvalue(node, attrname):
     return node.getAttribute(attrname) if node else ''

def get_nodevalue(node, index = 0):
    return node.childNodes[index].nodeValue if node else ''

def get_xmlnode(node, name):
    return node.getElementsByTagName(name) if node else []

def xml_to_string(filename='Guest.xml'):
    doc = minidom.parse(filename)
    return doc.toxml('UTF-8')

def get_xml_data(filename='Guest.xml'):
    doc = minidom.parse(filename) 
    root = doc.documentElement

    ## show the attributes of root node 
    print 'The customer name: %s' % (root.getAttribute("name"))
    print 'The customer id:   %d' % (int(root.getAttribute("id")))
    print 'The customer mail: %s' % (root.getAttribute("mail"))

    # get  the orderID node
    signode=root.getElementsByTagName("orderID")
    print 'The orderID of customer : %d' % (int(signode[0].getAttribute("id")))
    print 'The time of orderID : %s' % (signode[0].childNodes[0].data)

    # get the platform node
    signode=root.getElementsByTagName("platform")
    # show the data of platform
    print 'The platform id:%d' % (int(signode[0].getAttribute("id")))
    print 'The platform des:%s' % (signode[0].childNodes[0].data)

    # get all the module nodes
    module_nodes = get_xmlnode(root,'module')
    module_list=[]
    for node in module_nodes: 
        module_id = get_attrvalue(node,'id') 
        node_name = get_xmlnode(node,'modulename')
        node_type = get_xmlnode(node,'type')
        user_name =get_nodevalue(node_name[0]).encode('utf-8','ignore')
        node_type = get_nodevalue(node_type[0]).encode('utf-8','ignore') 
        module = {}
        module['id'] , module['modulename'] , module['type'] = (
            int(module_id), user_name , node_type
        )
        module_list.append(module)
    return module_list

def test_xmltostring():
    print xml_to_string()

def test_laod_xml():
    user_list = get_xml_data()
    for user in user_list :
        #print user['sex']
        print '-----------------------------------------------------'
        if user:
            user_str='module id:%d\nModuleName:%s\nType:%s' % (int(user['id']), user['modulename'], user['type'])
            print user_str
            print '=====================================================\n'
if __name__ == "__main__":
    #test_xmltostring()
    test_laod_xml()

编写完成后直接执行：python parseGuestXML.py即可完成xml里面各个tag的解析。

有几个注意的点：

（1）getElementsByTagName是获取所有的子节点； // root.getElementsByTagName("module")就是获取所有tag为module的子节点

（2）另外如果getElementsByTagName获取到对应tag的子节点如果再没有子节点，通过[0] 来后去当前唯一的节点；

          //  node=root.getElementsByTagName("platform")  ; node[0].getAttribute("id")) ; node[0].childNodes[0].data 

（3）存在子节点的就直接for循环轮训