Lab: Semantic Lifting - XML

Lab 10: Semantic Lifting - XML

Link to Discord server

https://discord.gg/t5dgPrK

Topics

Today's topic involves lifting data in XML format into RDF. XML stands for Extensible Markup Language and is used to... The goal is for you to learn an example of how we can convert unsemantic data into RDF.

Relevant Libraries/Functions

import requests import xml.etree.ElementTree as ET

Tasks

Task 1

Lift the XML data from 'http://feeds.bbci.co.uk/news/rss.xml' about news articles by BBC_News into RDF triples. Do this by parsing the XML using ElementTree (see import above). This means

Task 2

Parse trough the fictional XML data below and add the correct journalist as the writers of the news_articles from earlier. This means that e.g if the news article is written on a Tuesday, Thomas Smith is the one who wrote it. One way to do this is by checking if any of the days in the "whenWriting" attribute is contained in the news articles "pubDate".

<data>
    <news_publisher name="BBC News">
        <journalist whenWriting="Mon, Tue, Wed" >
            <firstname>Thomas</firstname>
            <lastname>Smith</lastname>
        </journalist>
        <journalist whenWriting="Thu, Fri" >
            <firstname>Joseph</firstname>
            <lastname>Olson</lastname>
        </journalist>
        <journalist whenWriting="Sat, Sun" >
             <firstname>Sophia</firstname>
             <lastname>Cruise</lastname>
        </journalist>
    </news_publisher>
</data

Task 3

Code to Get Started

from rdflib import Graph, Literal, Namespace, URIRef
from rdflib.namespace import RDF, XSD
import xml.etree.ElementTree as ET
import requests
import re

g = Graph()
ex = Namespace("http://example.org/")
prov = Namespace("http://www.w3.org/ns/prov#")
g.bind("ex", ex)
g.bind("ex", prov)


# url of rss feed
url = 'http://feeds.bbci.co.uk/news/rss.xml'

# creating HTTP response object from given url
resp = requests.get(url)

# saving the xml file
with open('test.xml', 'wb') as f:
    f.write(resp.content)

Hints Replacing characters with Dataframe:

Useful Reading

XML-parsing-python by geeksforgeeks.org