ElementTree解析xml文件-解析问题

Question

I have a problem parsing data from xml file. I'm using xml.etree.ElementTree to extract data from files and then save them into .csv. I have all the necessery modules installed on server. I am aware that there is bs4 module with BeutifulSoup, yet I would like to know if is possible to parse this data/xml file using ElementTree . Sorry if the answear is easy or obvious, yet I'm still very much a beginner and with this problem I could not name the problem in a way to find an answear.

While running python script written below I have no errors and no outcome. I don't really know what should I change. I can not find solution. I tried using different child.tag or attributes but with no result.

The xml file that I have problem with.:

<?xml version="1.0" encoding="utf-8"?>
<offer file_format="IOF" version="2.6" extensions="yes" xmlns="http://www.iai-shop.com/developers/iof.phtml">
    <product id="9" vat="23.0" code_on_card="BHA">
      <producer id="1308137276" name="BEAL"/>
      ...
      <price gross="175" net="142.28"/>
      <sizes>
        <size code_producer="3700288265272" code="9-uniw" weight="0">
          <stock id="0" quantity="-1"/>
          <stock id="1" quantity="4"/>
        </size>
      </sizes>
    </product>
    <product>
              ...
    </product>
              ...

and script that I tried to use (here to extract code_on_card, price net, quantity).

(I am aware that there are two childs: stock and quantity, and I'm completely fine with the second one overwrting the first one)

import requests
import os,sys
import csv
import xml.etree.ElementTree as ET

reload(sys)
sys.setdefaultencoding('utf-8')

xml_path = '/file.xml'

xml = ET.parse(xml_path)

with open('/home/file.csv', 'wb') as f:
    c = csv.writer(f, delimiter=';')
    for product in xml.iter('product'):
    product_id = product.attrib["code_on_card"]
        for child in product:
            if child.tag == 'price':
                if child.attrib["net"] != None:
                    hurt_net = child.attrib["net"]
        for size in product.iter('size'):
            for stock in size.iter('stock'):
                if 'quantity' in stock.attrib.keys():
                    quantity = stock.attrib["quantity"]

        line = product_id, hurt_net, quantity
        c.writerow(line)

Files that seem to me to be built on similar scheme work just fine (offer -> product ->child/attrib ), like this one:

<?xml version="1.0" encoding="UTF-8"?>
<offer file_format="IOF" version="2.5">
    <product id="2">
        <price gross="0.00" net="0.00" vat="23.0"/>
        <srp gross="0.00" net="0" vat="23.0"/>
        <sizes>
            <size id="0"  code="2-0"  weight="0" >
            </size>
        </sizes>
    </product>
        ...
    </product>
        ...

EDIT: Outcome should be .csv file containing multpile rows (each for each product in xml file) of code_on_card, price net, quantity. It should look like:

BC097B.50GD.O;70.81;37
BC097B.50.A;76.75;24
BC086C.50.B;76.75;29
BGRT.L;3;96.75;28
....

EDIT2 code as it is, after drec4s answear:

import requests
import os,sys
import csv
import xml.etree.cElementTree as ET

reload(sys)
sys.setdefaultencoding('utf-8')

xml_path = '/home/platne/serwer16373/dane/z_hurtowni/pobrane/beal2.xml'

root = ET.parse(xml_path)

ns = {'offer': 'http://www.iai-shop.com/developers/iof.phtml'}

products = root.getchildren()

with open('/home/platne/serwer16373/dane/z_hurtowni/stany_magazynowe/karol/bealKa.csv', 'wb') as f:
    c = csv.writer(f, delimiter=';')
    hurtownia = 'beal'
    for product in root.iter('product'):
        qtt = [1]
        code = product.get('code_on_card')
        hurt_net = product.find('price').get('net')
        for stock in product.find('sizes').find('size').getchildren():
            qtt.append(stock.get('quantity'))
        quantity = max(qtt)


        line = 'beal-'+str(code), hurt_net, quantity
        c.writerow(line)

somehow I'm getting AttributeError: 'ElementTree' object has no attribute 'getchildren' I've got Ele

Answer 1

This is how I would go and parse an xml file with namespaces. As per official documentation , the easiest way is to define a dictionary specifying the namespace.

from xml.etree import cElementTree as ET

root = ET.fromstring("""
<offer file_format="IOF" version="2.6" extensions="yes" xmlns="http://www.iai-shop.com/developers/iof.phtml">
    <product id="9" vat="23.0" code_on_card="BHA">
      <producer id="1308137276" name="BEAL"/>
      <price gross="175" net="142.28"/>
      <sizes>
        <size code_producer="3700288265272" code="9-uniw" weight="0">
          <stock id="0" quantity="-1"/>
          <stock id="1" quantity="4"/>
        </size>
      </sizes>
    </product>
</offer>
""")

ns = {'offer': 'http://www.iai-shop.com/developers/iof.phtml'}

products = root.getchildren()

for p in products:
    qtt = [] #to store all stock quantities
    product_id = p.get('code_on_card')
    hurt_net = p.find('offer:price', ns).get('net')
    for stock in p.find('offer:sizes', ns).find('offer:size', ns).getchildren():
        qtt.append(int(stock.get('quantity')))

    quantity = max(qtt) #or sum

line = (product_id, hurt_net, quantity)
print(line)

Outputs:

('BHA', '142.28', 4)

Also, I did not understand what was the stock quantity that you needed to extract, since you were only getting the last children( stock ) value (change the sum function to max or to whatever you need).