如何用Python minidom筛选XML中的WORK类型邮箱地址？

需要用Python提取XML中所有属于WORK类型的邮箱地址，筛选依据是<wd:ID wd:type="Communication_Usage_Type_ID">WORK</wd:ID>元素，目标是获取对应的<wd:Email_Address>内容。

目标XML示例 #

<?xml version="1.0" encoding="UTF-8"?>
<env:Envelope xmlns:env="http://schema.xmlsoap.org/soap/envelope/">
<env:Body>
    <wd:Get_Working_Response xmlns:wd="urn:com.workway/bsvc" 
                             wd:version="v40.1">
        <wd:Request_Criteria>
            <wd:Transaction_Log_Criteria_Data>
            </wd:Transaction_Log_Criteria_Data>
            <wd:Field_And_Parameter_Criteria_Data>
            </wd:Field_And_Parameter_Criteria_Data>
            <wd:Eligibility_Criteria_Data>
            </wd:Eligibility_Criteria_Data>
        </wd:Request_Criteria>
        <wd:Response_Filter>
        </wd:Response_Filter>
        <wd:Response_Group>
        </wd:Response_Group>
        <wd:Response_Results>
        </wd:Response_Results>
        <wd:Response_Data>
            <wd:Worker>
                <wd:Worker_Reference>
                    <wd:ID wd:type="WID">787878787878787</wd:ID>
                    <wd:ID wd:type="Employee_ID">123456</wd:ID>
                </wd:Worker_Reference>
                <wd:Worker_Descriptor>John Smith</wd:Worker_Descriptor>
                <wd:Worker_Data>
                    <wd:Worker_ID>123456</wd:Worker_ID>
                    <wd:User_ID>jsmith</wd:User_ID>
                    <wd:Personal_Data>
                            <wd:Email_Address_Data>
                                <wd:Email_Address>jsmith2222@gmail.com</wd:Email_Address>
                                <wd:Usage_Data wd:Public="0">
                                    <wd:Type_Data wd:Primary="1">
                                        <wd:Type_Reference>
                                            <wd:ID wd:type="WID">000000000000000</wd:ID>
                                            <wd:ID wd:type="Communication_Usage_Type_ID">HOME</wd:ID>
                                        </wd:Type_Reference>
                                    </wd:Type_Data>
                                </wd:Usage_Data>
                                <wd:Email_Reference>
                                    <wd:ID wd:type="WID">99999999999999999999999</wd:ID>
                                    <wd:ID wd:type="Email_ID">EMAIL_REFERENCE-3-3960</wd:ID>
                                </wd:Email_Reference>
                                <wd:ID>EMAIL_REFERENCE-3-3960</wd:ID>
                            </wd:Email_Address_Data>
                            <wd:Email_Address_Data>
                                <wd:Email_Address>jsmith@something.com</wd:Email_Address>
                                <wd:Usage_Data wd:Public="1">
                                    <wd:Type_Data wd:Primary="1">
                                        <wd:Type_Reference>
                                            <wd:ID wd:type="WID">999999999999999999999999999</wd:ID>
                                            <wd:ID wd:type="Communication_Usage_Type_ID">WORK</wd:ID>
                                        </wd:Type_Reference>
                                    </wd:Type_Data>
                                </wd:Usage_Data>
                                <wd:Email_Reference>
                                    <wd:ID wd:type="WID">999999999999999999999999</wd:ID>
                                    <wd:ID wd:type="Email_ID">EMAIL_REFERENCE-3-4017</wd:ID>
                                </wd:Email_Reference>
                                <wd:ID>EMAIL_REFERENCE-3-4017</wd:ID>
                            </wd:Email_Address_Data>
                            </wd:Personal_Data>
                    </wd:Worker_Data>   
            </wd:Worker>
        </wd:Response_Data>
    </wd:Get_Working_Response>
</env:Body>
</env:Envelope>

现有代码（已筛选出包含WORK的ID元素，但无法关联到对应的Email_Address_Data） #

xmlDoc = minidom.parse('XML_Example.xml')

workelements =[]
lNodesWithLevel1 = xmlDoc.getElementsByTagName('wd:ID')
for mynodes in lNodesWithLevel1:
    if mynodes.firstChild.nodeValue == 'WORK':
        workelements.append(mynodes)

lNodesWithLevel2 = [lNode for lNode in xmlDoc.getElementsByTagName('wd:Email_Address_Data')
                 if lNode.getElementsByTagName('wd:ID') == li]

方法一：改进minidom代码 #

通过DOM元素的parentNode属性向上遍历，找到对应的Email_Address_Data元素，再提取邮箱地址：

from xml.dom import minidom

xmlDoc = minidom.parse('XML_Example.xml')
work_emails = []

# 遍历所有符合条件的ID元素
for id_node in xmlDoc.getElementsByTagName('wd:ID'):
    # 检查是否是WORK类型的Communication_Usage_Type_ID
    if id_node.getAttribute('wd:type') == 'Communication_Usage_Type_ID' and id_node.firstChild.nodeValue == 'WORK':
        # 向上遍历父节点，找到Email_Address_Data
        current_node = id_node
        while current_node and current_node.tagName != 'wd:Email_Address_Data':
            current_node = current_node.parentNode
        if current_node:
            # 提取邮箱地址
            email_node = current_node.getElementsByTagName('wd:Email_Address')[0]
            work_emails.append(email_node.firstChild.nodeValue)

print(work_emails)  # 输出: ['jsmith@something.com']

方法二：使用lxml库（更简便） #

lxml支持XPath查询，能直接定位到符合条件的邮箱元素，代码更简洁：

首先安装lxml：

pip install lxml

然后编写代码：

from lxml import etree

# 定义命名空间
ns = {
    'env': 'http://schema.xmlsoap.org/soap/envelope/',
    'wd': 'urn:com.workway/bsvc'
}

tree = etree.parse('XML_Example.xml')
# 使用XPath直接筛选WORK类型的邮箱
work_emails = tree.xpath('//wd:Email_Address_Data[.//wd:ID[@wd:type="Communication_Usage_Type_ID" and text()="WORK"]]/wd:Email_Address/text()', namespaces=ns)

print(work_emails)  # 输出: ['jsmith@something.com']

内容的提问来源于stack exchange，提问作者Nick