TypeError： write() 得到一个意外的关键字参数 'pretty_print'

Question

我正在编写一个python脚本，它将在我的jenkins作业的config.xml中添加一个新的标签/元素。

这是我的脚本看起来像:-

#!/usr/bin/python
import os, fnmatch, pdb, re, string, fileinput, sys
from lxml import etree
def find(pattern, path):
result = []
for root, dirs, files in os.walk(path):
    for name in files:
        if fnmatch.fnmatch(name, pattern):
            result.append(os.path.join(root, name))
return result
finalresult = find('config.xml', './')
print finalresult
def writexml(filepath):
tree = etree.parse(filepath)
root = tree.getroot()
a=[]
for v in root.iter('publishers'):
        for a in v:
            if a.tag == "hudson.plugins.emailext.ExtendedEmailPublisher":
                t1=etree.SubElement(v,'org.jenkinsci.plugins.postbuildscript.PostBuildScript',{'plugin':"postbuildscript@017"})
                t2=etree.SubElement(t1,"buildSteps")
                t3=etree.SubElement(t2,'hudson.tasks.Shell')
                t4=etree.SubElement(t3,"command")
                t4.text = "bash -x /d0/jenkins/scripts/parent-pom-enforcer.sh"
                t5 = etree.SubElement(t1,'scriptOnlyIfSuccess')
                t5.text = "false"
                t6 = etree.SubElement(t1,'scriptOnlyIfFailure')
                t6.text = "false"
                t7= etree.SubElement(t1,'markBuildUnstable')
                t7.text = "true"
tree.write(filepath,pretty_print=True)
findMavenProject=[]
for i in finalresult:
tree = etree.parse(i)
root = tree.getroot()
for v in  root.iter('hudson.tasks.Maven'):
    if v.tag == "hudson.tasks.Maven":
        writexml(i)
        findMavenProject.append(i)
print findMavenProject

当我执行这个脚本时，我得到以下错误:

  running with cElementTree on Python 2.5+
  ['./jen1/config.xml', './jen2/config.xml', './jen3/config.xml',     './jen4/config.xml']
  Traceback (most recent call last):
  File "./find-test.py", line 50, in <module>
  writexml(i)
  File "./find-test.py", line 41, in writexml
  tree.write(filepath,pretty_print=True)
  TypeError: write() got an unexpected keyword argument 'pretty_print'

我谷歌这个错误，发现，我应该使用"lxml"。我用它，但即使在那之后，我得到同样的错误。我正在使用Python 2.7.6版本.

什么线索吗?

Answer 1

Python标准库xml.etree.ElementTree.write()没有pretty_print参数。

在lxml 的最新版本中该方法的版本执行。我刚刚用lxml 3.3.3测试了它，http://lxml.de/tutorial.html#serialisation上的文档提到了它。

您可能正在使用旧版本的lxml，或者不知何故仍在使用标准库的旧库副本。

Answer 2

tree.write(filepath,pretty_print=True)是错误的。

正确路径:tree.write(filepath)或tree.tostring(root, pretty_print=True)。

---

详细解释:

tree是ElementTree Objects，而write没有pretty_print参数。

write(file, encoding="us-ascii", xml_declaration=None, default_namespace=None, method="xml")

将元素树写入文件，如XML。File是一个文件名，或一个为写入而打开的文件对象。encoding[1]为输出编码(默认为US-ASCII)。xml_declaration控制是否应该将XML声明添加到文件中。从不使用False，始终使用True，仅当不是US-ASCII或UTF-8时使用None(默认为None)。default_namespace设置默认的XML命名空间(对于" xmlns ")。方法为"xml"、"html"或"text"(默认为"xml")。返回一个编码字符串。

xml.etree.ElementTree。文档元素

---

回答另一个问题，用Python打印XML:

import xml.dom.minidom
my_xml_doc = xml.dom.minidom.parse(xml_fname) # or xml.dom.minidom.parseString(xml_string)
pretty_xml_as_string = my_xml_doc.toprettyxml()

---

更新2

lxml。树确实有pretty_print参数，如下所示:

etree.tostring(root, pretty_print=True)

lxml docs

感谢@RemcoGerlich

Answer 3

下面代码的问题是它使用制表符创建了重复的空行。如果您试图编辑现有的xml.

import xml.dom.minidom
xml = xml.dom.minidom.parse(xml_fname) # or xml.dom.minidom.parseString(xml_string)
pretty_xml_as_string = xml.toprettyxml()

解决方案:-我试了下面的代码，它为我工作。

from lxml import etree as ET
import xml.dom.minidom      
def writexml(filepath):
    parser = ET.XMLParser(resolve_entities=False, strip_cdata=False)
    tree = ET.parse(filepath, parser)
    root = tree.getroot()
    a=[]     
    for v in root.iter('publishers'):
        for a in v:
            if a.tag == "hudson.plugins.emailext.ExtendedEmailPublisher":
                t1=ET.SubElement(v,'org.jenkinsci.plugins.postbuildscript.PostBuildScript',{'plugin':"postbuildscript@0.17"})
                t2=ET.SubElement(t1,"buildSteps")
                t3=ET.SubElement(t2,'hudson.tasks.Shell')
                t4=ET.SubElement(t3,"command")
                t4.text = "bash -x /d0/jenkins/scripts/parent-pom-enforcer.sh"
                t5 = ET.SubElement(t1,'scriptOnlyIfSuccess')
                t5.text = "false"
                t6 = ET.SubElement(t1,'scriptOnlyIfFailure')
                t6.text = "false"
                t7= ET.SubElement(t1,'markBuildUnstable')
                t7.text = "true"
    xml1 = xml.dom.minidom.parseString(ET.tostring(root, pretty_print=True))
    pretty_xml_as_string = xml1.toprettyxml()
    f = open(filepath, "w")
    for v in str(pretty_xml_as_string).split("n"):
        if v.strip():
            f.write(v+"n")
    f.close()

writexml('test.xml') #为函数writexml提供文件的完整路径