Solving problem is about exposing yourself to as many situations as possible like Parsing HTML using Python and practice these strategies over and over. With time, it becomes second nature and a natural way you approach any problems in general. Big or small, always start with a plan, use other strategies mentioned here till you are confident and ready to code the solution.
In this post, my aim is to share an overview the topic about Parsing HTML using Python, which can be followed any time. Take easy to follow this discuss.
I’m looking for an HTML Parser module for Python that can help me get the tags in the form of Python lists/dictionaries/objects.
If I have a document of the form:
<html>
<head>Heading</head>
<body attr1='val1'>
<div class='container'>
<div id='class'>Something here</div>
<div>Something else</div>
</div>
</body>
</html>
then it should give me a way to access the nested tags via the name or id of the HTML tag so that I can basically ask it to get me the content/text in the div tag with class='container' contained within the body tag, or something similar.
If you’ve used Firefox’s “Inspect element” feature (view HTML) you would know that it gives you all the tags in a nice nested manner like a tree.
I’d prefer a built-in module but that might be asking a little too much.
I went through a lot of questions on Stack Overflow and a few blogs on the internet and most of them suggest BeautifulSoup or lxml or HTMLParser but few of these detail the functionality and simply end as a debate over which one is faster/more efficent.
Answer #1:
So that I can ask it to get me the content/text in the div tag with class=’container’ contained within the body tag, Or something similar.
try:
from BeautifulSoup import BeautifulSoup
except ImportError:
from bs4 import BeautifulSoup
html = #the HTML code you've written above
parsed_html = BeautifulSoup(html)
print(parsed_html.body.find('div', attrs={'class':'container'}).text)
You don’t need performance descriptions I guess – just read how BeautifulSoup works. Look at its official documentation.
Answer #2:
I guess what you’re looking for is pyquery:
pyquery: a jquery-like library for python.
An example of what you want may be like:
from pyquery import PyQuery
html = # Your HTML CODE
pq = PyQuery(html)
tag = pq('div#id') # or tag = pq('div.class')
print tag.text()
And it uses the same selectors as Firefox’s or Chrome’s inspect element. For example:
The inspected element selector is ‘div#mw-head.noprint’. So in pyquery, you just need to pass this selector:
pq('div#mw-head.noprint')
Answer #3:
Here you can read more about different HTML parsers in Python and their performance. Even though the article is a bit dated it still gives you a good overview.
Python HTML parser performance
I’d recommend BeautifulSoup even though it isn’t built in. Just because it’s so easy to work with for those kinds of tasks. Eg:
import urllib2
from BeautifulSoup import BeautifulSoup
page = urllib2.urlopen('http://www.google.com/')
soup = BeautifulSoup(page)
x = soup.body.find('div', attrs={'class' : 'container'}).text
Answer #4:
Compared to the other parser libraries lxml is extremely fast:
- http://blog.dispatched.ch/2010/08/16/beautifulsoup-vs-lxml-performance/
- http://www.ianbicking.org/blog/2008/03/python-html-parser-performance.html
And with cssselect it’s quite easy to use for scraping HTML pages too:
from lxml.html import parse
doc = parse('http://www.google.com').getroot()
for div in doc.cssselect('a'):
print '%s: %s' % (div.text_content(), div.get('href'))
Answer #5:
I recommend lxml for parsing HTML. See “Parsing HTML” (on the lxml site).
In my experience Beautiful Soup messes up on some complex HTML. I believe that is because Beautiful Soup is not a parser, rather a very good string analyzer.
Answer #6:
I recommend using justext library:
https://github.com/miso-belica/jusText
Usage:
Python2:
import requests
import justext
response = requests.get("http://planet.python.org/")
paragraphs = justext.justext(response.content, justext.get_stoplist("English"))
for paragraph in paragraphs:
print paragraph.text
Python3:
import requests
import justext
response = requests.get("http://bbc.com/")
paragraphs = justext.justext(response.content, justext.get_stoplist("English"))
for paragraph in paragraphs:
print (paragraph.text)
Answer #7:
I would use EHP
Here it is:
from ehp import *
doc = '''<html>
<head>Heading</head>
<body attr1='val1'>
<div class='container'>
<div id='class'>Something here</div>
<div>Something else</div>
</div>
</body>
</html>
'''
html = Html()
dom = html.feed(doc)
for ind in dom.find('div', ('class', 'container')):
print ind.text()
Output:
Something here
Something else
