如何使用 Python 和 SAX 更好地读取和解析 xml 文件？

Question

Windows 11/Python 3.8.10 - Using Spyder Python IDE and PyCharm

Hey all, newish to python app dev and have a big project to parse xml files. Trying to write a python program for it. Below is a very small sample of the xml file data structure I am working with.

     <PillCall XMLInstanceID="98089D9A-768A-4FA0-A7CD-DC5966EB5B06" PillCallID="49" VersionNumber="1.2">
     </PillCall>

These xml files will be huge. Eventually this will need to be able to process multiple large files with a lot of data 24/7 concurrently. Eventually parsing the data and saving it to a db, then after modification, creating an new modified xml file based on the current data in db.

Here is my sample program, from Python Spyder IDE: -- I have tried a bunch of other methods but the SAX method has been the best to understand for me personally so far. I am sure there are better ways though.

     import xml.sax

class XMLHandler(xml.sax.ContentHandler):
    def __init__(self):
        self.CurrentData = ""
        self.pillcall = ""
        self. pillcallid= ""
        self.vernum = ""

   # Call when an element starts
    def startElement(self, tag, attributes):
        self.CurrentData = tag
        if(tag == "PillCall"):
            print("*****PillCall*****")
            title = attributes["XMLInstanceID"]
            print("XMLInstanceID:=", title) #How at add multiple values/strings here?   
   #        print(sorted()


# create an XMLReader
parser = xml.sax.make_parser()

# turn off namepsaces
parser.setFeature(xml.sax.handler.feature_namespaces, 0)

# override the default ContextHandler
Handler = XMLHandler()
parser.setContentHandler( Handler )
parser.parse("xmltest10.xml")

My output is this:

PillCall XMLInstanceID:= 98089D9A-768A-4FA0-A7CD-DC5966EB5B06

I have tried many different ways to read the whole string with element tree and beautifulsoap but can't get it to work. I also get no output with running this program in PyCharm.

Here is some extra python/sax code that I have been messing with as well but haven't got it to work right either.

I just need to be able to clearly read the data and parse it to a new file for now. And also how to loop through it and find all the data to ouput. Thanks for any and all help!!

     # Call when an elements ends
    def endElement(self, tag):
         if(self.CurrentData != "/PillCall"):
             print("End of PillCall:", self.pillcall)
         elif(self.CurrentData == "PillCallID"):
             print("PillCallID:=", self.pillcallid)
         elif(self.CurrentData == "VersionNumber"):
             print("VersionNumber:=", self.vernum)
         self.CurrentData = ""

    # Call when a character is read
    def characters(self, content):
         if(self.CurrentData == "PillCall"):
             self.pillcall = content
         elif(self.CurrentData == "qty"):
             self.pillcallid = content
         elif(self.CurrentData == "company"):
             self.vernum = content

Answer 1

Using BeautifulSoup's find_all may be what you're looking for...

Given:

text = """
     <PillCall XMLInstanceID="98089D9A-768A-4FA0-A7CD-DC5966EB5B06" PillCallID="49" VersionNumber="1.2">
     </PillCall>
"""

from bs4 import BeautifulSoup

soup = BeautifulSoup(text, 'xml')

for result in soup.find_all('PillCall'):
    print(result.attrs)

Output:

{'PillCallID': '49',
 'VersionNumber': '1.2',
 'XMLInstanceID': '98089D9A-768A-4FA0-A7CD-DC5966EB5B06'}