基于xml标记标题获取文本

Question

设置

我对xml和ubl xml很陌生。

试图使用.xml将下面的ElementTree发票读入Python。

<?xml version="1.0" encoding="UTF-8"?>
<Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2" xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2" xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2&#xA;http://docs.oasis-open.org/ubl/os-UBL-2.1/xsd/maindoc/UBL-Invoice-2.1.xsd">
  <cbc:UBLVersionID>2.1</cbc:UBLVersionID>
  <cbc:CustomizationID>urn:www.cenbii.eu:transaction:biitrns010:ver2.0:extended:urn:www.peppol.eu:bis:peppol4a:ver2.0:extended:urn:www.simplerinvoicing.org:si:si-ubl:ver1.1.x</cbc:CustomizationID>
  <cbc:ProfileID>urn:www.cenbii.eu:profile:bii04:ver2.0</cbc:ProfileID>
  <cbc:ID>201909638</cbc:ID>
  <cbc:IssueDate>2019-11-01</cbc:IssueDate>
  <cbc:InvoiceTypeCode listAgencyID="6" listID="UNCL1001">380</cbc:InvoiceTypeCode>
  <cbc:DocumentCurrencyCode listAgencyID="6" listID="ISO 4217 Alpha">EUR</cbc:DocumentCurrencyCode>
  <cac:OrderReference>
  # other stuff
</Invoice>

如果运行root[4].text，将得到以字符串形式返回的IssueDate标记的文本，即'2019-11-01'。

问题

我想获得基于标签标题的文本。

• root.find('IssueDate').text
• root.find('cbc:IssueDate').text

给AttributeError: 'NoneType' object has no attribute 'text'。

问题

如何根据标签标题IssueDate获取文本？

更普遍地说，如何根据标签的标题获取任何标签的文本？

Answer 1

import xml.etree.ElementTree as ET   

xml_string="""<?xml version="1.0" encoding="UTF-8"?>
    <Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2" xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2" xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2&#xA;http://docs.oasis-open.org/ubl/os-UBL-2.1/xsd/maindoc/UBL-Invoice-2.1.xsd">
      <cbc:UBLVersionID>2.1</cbc:UBLVersionID>
      <cbc:CustomizationID>urn:www.cenbii.eu:transaction:biitrns010:ver2.0:extended:urn:www.peppol.eu:bis:peppol4a:ver2.0:extended:urn:www.simplerinvoicing.org:si:si-ubl:ver1.1.x</cbc:CustomizationID>
      <cbc:ProfileID>urn:www.cenbii.eu:profile:bii04:ver2.0</cbc:ProfileID>
      <cbc:ID>201909638</cbc:ID>
      <cbc:IssueDate>2019-11-01</cbc:IssueDate>
      <cbc:InvoiceTypeCode listAgencyID="6" listID="UNCL1001">380</cbc:InvoiceTypeCode>
      <cbc:DocumentCurrencyCode listAgencyID="6" listID="ISO 4217 Alpha">EUR</cbc:DocumentCurrencyCode>
      <cac:OrderReference>ABC</cac:OrderReference>
    </Invoice>"""

root = ET.fromstring(xml_string)

这里我使用字符串作为输入，您也使用XML文件作为输入。现在，要首先获得基于标签标题的文本，您需要知道标签的名称是什么。

for child in root:
    print(child.tag, child.attrib)

输出：

{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}UBLVersionID {}
{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}CustomizationID {}
{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}ProfileID {}
{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}ID {}
{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}IssueDate {}
{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}InvoiceTypeCode {'listAgencyID': '6', 'listID': 'UNCL1001'}
{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}DocumentCurrencyCode {'listAgencyID': '6', 'listID': 'ISO 4217 Alpha'}
{urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2}OrderReference {}

您可以看到，您的逻辑是正确的，以找到文本，但您提供了错误的标题。由于发票属性，在这里我们无法使用'cbc:IssueDate'或'IssueDate'直接找到文本

如果你用过

root.find("{urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2}IssueDate").text

输出：

'2019-11-01'

这里，由于标签标题中的"urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2" cbc，在IssueDate前面添加了。如果不是这样的话，"urn:oasis:names:specification:ubl:schema:xsd:Invoice-2"就会被添加到前面。

我希望这能回答你的问题。

Answer 2

您可以使用BeautifulSoup

from bs4 import BeautifulSoup as BS4

xml_test = """<?xml version="1.0" encoding="UTF-8"?>
    <Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2" xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2" xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2&#xA;http://docs.oasis-open.org/ubl/os-UBL-2.1/xsd/maindoc/UBL-Invoice-2.1.xsd">
      <cbc:UBLVersionID>2.1</cbc:UBLVersionID>
      <cbc:CustomizationID>urn:www.cenbii.eu:transaction:biitrns010:ver2.0:extended:urn:www.peppol.eu:bis:peppol4a:ver2.0:extended:urn:www.simplerinvoicing.org:si:si-ubl:ver1.1.x</cbc:CustomizationID>
      <cbc:ProfileID>urn:www.cenbii.eu:profile:bii04:ver2.0</cbc:ProfileID>
      <cbc:ID>201909638</cbc:ID>
      <cbc:IssueDate>2019-11-01</cbc:IssueDate>
      <cbc:InvoiceTypeCode listAgencyID="6" listID="UNCL1001">380</cbc:InvoiceTypeCode>
      <cbc:DocumentCurrencyCode listAgencyID="6" listID="ISO 4217 Alpha">EUR</cbc:DocumentCurrencyCode>
      <cac:OrderReference>ABC</cac:OrderReference>
    </Invoice>"""

soup = BS4(xml_test)

tag = soup.find("cbc:issuedate")

print(tag.text)

结果将是

2019-11-01

如果您有许多issue dates，您可以使用

tags = soup.findAll("cbc:issuedate")
for tag in tags:
    print(tag.text)

我希望它能帮上忙

Answer 3

您也可以使用SimplifiedDoc。

from simplified_scrapy.simplified_doc import SimplifiedDoc 
html = '''
<?xml version="1.0" encoding="UTF-8"?>
<Invoice xmlns="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2" xmlns:cac="urn:oasis:names:specification:ubl:schema:xsd:CommonAggregateComponents-2" xmlns:cbc="urn:oasis:names:specification:ubl:schema:xsd:CommonBasicComponents-2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="urn:oasis:names:specification:ubl:schema:xsd:Invoice-2&#xA;http://docs.oasis-open.org/ubl/os-UBL-2.1/xsd/maindoc/UBL-Invoice-2.1.xsd">
  <cbc:UBLVersionID>2.1</cbc:UBLVersionID>
  <cbc:CustomizationID>urn:www.cenbii.eu:transaction:biitrns010:ver2.0:extended:urn:www.peppol.eu:bis:peppol4a:ver2.0:extended:urn:www.simplerinvoicing.org:si:si-ubl:ver1.1.x</cbc:CustomizationID>
  <cbc:ProfileID>urn:www.cenbii.eu:profile:bii04:ver2.0</cbc:ProfileID>
  <cbc:ID>201909638</cbc:ID>
  <cbc:IssueDate>2019-11-01</cbc:IssueDate>
  <cbc:InvoiceTypeCode listAgencyID="6" listID="UNCL1001">380</cbc:InvoiceTypeCode>
  <cbc:DocumentCurrencyCode listAgencyID="6" listID="ISO 4217 Alpha">EUR</cbc:DocumentCurrencyCode>
  <cac:OrderReference>
  # other stuff
</Invoice>
'''
doc = SimplifiedDoc(html)
print (doc.getElementByTag('cbc:IssueDate').text) # get one
lst = doc.getElementByTag('Invoice').getChildren() # get all
for item in lst:
  print (item.tag,item.text)