Question

我尝试使用Python 3.3将XML文件转换为YAML。这是我的代码：

#! /etc/python3

test_filename_input = './reference-conversions/wikipedia-example.xml'
test_filename_output = 'wikipedia-example_xml_read-as-binary.yaml'

file_object = open( test_filename_input, 'rb')
data_in = file_object.read()
file_object.close()

from xml.dom.minidom import parseString
document_object = parseString( data_in)

import yaml
stream = open( test_filename_output, 'w')
yaml.dump( document_object, stream)
stream.close()

作为参考，我使用了来自here的XML文件：

<person>
  <firstName>John</firstName>
  <lastName>Smith</lastName>
  <age>25</age>
  <address>
    <streetAddress>21 2nd Street</streetAddress>
    <city>New York</city>
    <state>NY</state>
    <postalCode>10021</postalCode>
  </address>
  <phoneNumbers>
    <phoneNumber type="home">212 555-1234</phoneNumber>
    <phoneNumber type="fax">646 555-4567</phoneNumber>
  </phoneNumbers>
  <gender>
    <type>male</type>
  </gender>
</person>

应该会产生这样的结果：

---
  firstName: John
  lastName: Smith
  age: 25
  address: 
        streetAddress: 21 2nd Street
        city: New York
        state: NY
        postalCode: 10021

  phoneNumber: 
        -  
            type: home
            number: 212 555-1234
        -  
            type: fax
            number: 646 555-4567
  gender: 
        type: male

然而，结果是：

&id001 !!python/object/new:xml.dom.minidom.Document
state: !!python/tuple
- implementation: !!python/object:xml.dom.minidom.DOMImplementation {}
- _elem_info: {}
  _id_cache: {}
  _id_search_stack: null
  childNodes: !!python/object/new:xml.dom.minicompat.NodeList
    listitems:
    - &id039 !!python/object/new:xml.dom.minidom.Element
      state: !!python/tuple
      - null
      - _attrs: null
        _attrsNS: null
        childNodes: !!python/object/new:xml.dom.minicompat.NodeList
          listitems:
          - &id045 !!python/object/new:xml.dom.minidom.Text
            state: !!python/tuple
            - null
            - _data: "\n  "
              nextSibling: &id002 !!python/object/new:xml.dom.minidom.Element
                state: !!python/tuple
                - null
                - _attrs: null
                  _attrsNS: null
                  childNodes: !!python/object/new:xml.dom.minicompat.NodeList
                    listitems:
[...]

任何想法，如何让PyYAML过滤掉xml.dom.minidom中的对象 - 或使用xml.dom.minidom的任何替代方法？

谢谢！

Answer 1

我找到了一个XML to YAML converter，但我不得不在第92行做一个小改动：

outStr = yaml.dump(out)

更改为

outStr = yaml.safe_dump(out)

删除输出中的所有!!python/unicode标记。我已经通过shell命令行测试了脚本，它工作正常;我确信这只是一个简单的翻译，可以让它在Python命令行中运行。

修改

我还添加了自己的打印方法，使输出看起来更像您最初发布的内容：

def prettyPrint(node, level): childPrint = 0 attrPrint = 0 for x in node: try: if x['attributes']: attrPrint = 1 for l in range(0, level): sys.stdout.write("\t") for a in x['attributes']: sys.stdout.write("- %s: %s\n" % (a, x['attributes'][a])) except KeyError: try: if x['children']: childPrint = 1 for l in range(0, level): sys.stdout.write("\t") sys.stdout.write("%s:\n" % x['name']) prettyPrint(x['children'], level+1) except KeyError: pass finally: if not childPrint: printNextNode(x, level, attrPrint) attrPrint = 0 else: childPrint = 0 def printNextNode(node, level, attrPrint): for l in range(0, level): sys.stdout.write("\t") if attrPrint: sys.stdout.write(' ') sys.stdout.write("%s: %s\n" % (node['name'], node['text']))

然后在convertXml2Yaml函数中调用它：

sys.stdout.write('%s:\n' % out['name']) prettyPrint(out['children'], 1)

Answer 2

这是解决xml.dom问题的方法，并提供了一种方法来映射节点既具有内容又具有属性或子级的模棱两可的情况。对于上面的示例输入，它产生：

$ python3 yamlout.py person.xml
---
person:
  firstName: John
  lastName: Smith
  age: 25
  address:
    streetAddress: 21 2nd Street
    city: New York
    state: NY
    postalCode: 10021
  phoneNumbers:
    phoneNumber:
      _xml_node_content: 212 555-1234 
      type: home # Attribute
    phoneNumber:
      _xml_node_content: 646 555-4567 
      type: fax # Attribute
  gender:
    type: male

实现yamlout.py：

import sys
import xml.etree.ElementTree as ET

if len(sys.argv) != 2:
    sys.stderr.write("Usage: {0} <file>.xml".format(sys.argv[0]))

XML_NODE_CONTENT = '_xml_node_content'
ATTR_COMMENT = '# Attribute'
def yamlout(node, depth=0):
    if not depth:
        sys.stdout.write('---\n')
    # Nodes with both content AND nested nodes or attributes
    # have no valid yaml mapping. Add  'content' node for that case
    nodeattrs = node.attrib
    children = list(node)
    content = node.text.strip() if node.text else ''
    if content:
        if not (nodeattrs or children):
            # Write as just a name value, nothing else nested
            sys.stdout.write(
                '{indent}{tag}: {text}\n'.format(
                    indent=depth*'  ', tag=node.tag, text=content or ''))
            return
        else:
            nodeattrs[XML_NODE_CONTENT] = node.text

    sys.stdout.write('{indent}{tag}:\n'.format(
        indent=depth*'  ', tag=node.tag))

    # Indicate difference node attributes and nested nodes
    depth += 1
    for n,v in nodeattrs.items():
        sys.stdout.write(
            '{indent}{n}: {v} {c}\n'.format(
                indent=depth*'  ', n=n, v=v,
                c=ATTR_COMMENT if n!=XML_NODE_CONTENT else ''))
    # Write nested nodes
    for child in children:
        yamlout(child, depth)

with open(sys.argv[1]) as xmlf:
    tree = ET.parse(xmlf)
    yamlout(tree.getroot())

Python 3.3：将XML转换为YAML

2 个答案: