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xml parsing with extra '\n' and whitespaces using lxml library

Time:11-19

I wrote a python program with lxml library to parse a xml file using its xpath. The value and xpath are all correct but it returns many '\n' and white spaces just like the xml file's formatting.

here is my code:

from lxml import etree
from xml.dom import minidom


#data = minidom.parse('D:/LocalSpark/bitmap.xml')
sigxml =  etree.parse('D:/LocalSpark/bitmap.xml',etree.XMLParser(remove_blank_text=True, load_dtd=True))
xpath = '/OneMessage[@Name="NR RRCReconfiguration"]/BalongMessage/Content/L3MessageContent/DL-DCCH-Message/message/c1/rrcReconfiguration/criticalExtensions/rrcReconfiguration/measConfig/measObjectToAddModList/MeasObjectToAddMod/measObject/measObjectNR/referenceSignalConfig/ssb-ConfigMobility/ssb-ToMeasure/setup/mediumBitmap'
info =  10000000    

for node in sigxml.xpath(xpath):
    print('node:     ', node)
    print('node.tag: ',node.tag)
    print('node.text:',node.text)
    print('node.item:',node.items())   
    print('node.attrib:',node.attrib)
    
    if info == node.text:
        print("%s info do exist!"%info)
    else:
        print("%s info do not exist!!!"%info)

here is the xml file:

<OneMessage Name="NR RRCReconfiguration" MsgTimeStamp="1668594368290"><BalongMessage><Header><usRsvd>4608</usRsvd><ucbMdmId>0</ucbMdmId><ucbMsgType>3</ucbMsgType><ucbRsvd>0</ucbRsvd><ulMsgClsID>26080000</ulMsgClsID><ullbTimeStamp>1853637.763054</ullbTimeStamp><ullbCpuTransID>38693</ullbCpuTransID><usSocpTransID>20388</usSocpTransID><ullLocalTime>133129368818699187</ullLocalTime><ulTransNo>6107</ulTransNo><ulSendPID>131072</ulSendPID><ulRecvPID>0</ulRecvPID><ulPrimID>00000003</ulPrimID><ucbOtaDirect>DL(1)</ucbOtaDirect><ucbPrintLevel>63</ucbPrintLevel><ulDataSize>56</ulDataSize></Header><Content><L3MessageContent><DL-DCCH-Message>
    <message>
        <c1>
            <rrcReconfiguration>
                <criticalExtensions>
                    <rrcReconfiguration>
                        <measConfig>
                            <measObjectToAddModList>
                                <MeasObjectToAddMod>
                                    <measObject>
                                        <measObjectNR>
                                            <referenceSignalConfig>
                                                <ssb-ConfigMobility>
                                                    <ssb-ToMeasure>
                                                        <setup>
                                                            <mediumBitmap>
                                                                10000000
                                                            </mediumBitmap>
                                                        </setup>
                                                    </ssb-ToMeasure>                                                   
                                                </ssb-ConfigMobility>
                                            </referenceSignalConfig>                                           
                                        </measObjectNR>
                                    </measObject>
                                </MeasObjectToAddMod>
                            </measObjectToAddModList>
                        </measConfig>
                    </rrcReconfiguration>
                </criticalExtensions>
            </rrcReconfiguration>
        </c1>
    </message>
</DL-DCCH-Message>
</L3MessageContent></Content></BalongMessage></OneMessage>

Here is the result:

node:      <Element mediumBitmap at 0x22e3c645f80>
node.tag:  mediumBitmap
node.text:
                                                                10000000

node.item: []
node.attrib: {}
10000000 info do not exist!!!

My problem is that clearly the code can read and find mediumBitmap this element but as it shows in xml file, it has \n before and after it. So when the program goes on, it returns that mediumBitmap's text value is

\n 10000000 \n

but not just 10000000

It is a standard xml from a project so I can't edit it.

I tried to add remove_blank_text=True to parse or using minidom

all failed

CodePudding user response:

There are many ways to strip spaces and newlines, however, a simple technique would be to use regex to remove them.

The critical line is this one:

int(re.sub(r'[\\n\s]*', '', node.text))

Which searches and substitutes all carriage returns and spaces in node.text and converts them to '' nothing. Then cast to int so that the info variable matches accordingly.

Here is the code:

from lxml import etree
from xml.dom import minidom
import re


#data = minidom.parse('D:/LocalSpark/bitmap.xml')
sigxml =  etree.parse('D:/LocalSpark/bitmap.xml',etree.XMLParser(remove_blank_text=True, load_dtd=True))
xpath = '/OneMessage[@Name="NR RRCReconfiguration"]/BalongMessage/Content/L3MessageContent/DL-DCCH-Message/message/c1/rrcReconfiguration/criticalExtensions/rrcReconfiguration/measConfig/measObjectToAddModList/MeasObjectToAddMod/measObject/measObjectNR/referenceSignalConfig/ssb-ConfigMobility/ssb-ToMeasure/setup/mediumBitmap'
info =  10000000    

for node in sigxml.xpath(xpath):
    print('node:     ', node)
    print('node.tag: ',node.tag)
    print('node.text:',node.text)
    print('node.item:',node.items())   
    print('node.attrib:',node.attrib)
    
    if info == int(re.sub(r'[\\n\s]*', '', node.text)):
        print("%s info do exist!"%info)
    else:
        print("%s info do not exist!!!"%info)
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