i am using Beautifulsoup4 and Soupstrainer with Python 3.3 for getting all links from a webpage. The following is the important code-snippet:
r = requests.get(adress, headers=headers)
for link in BeautifulSoup(r.text, parse_only=SoupStrainer('a')):
if hasattr(link, 'href'):
I tested some webpages and it works very well but today when using
adress = 'http://www.goldentigercasino.de/'
I recognized that hasattr(link, 'href') always returns TRUE even when there is no such 'href' field, like in the goldentigercasino.de example. Because of that im getting troubles for late using link['href'] because its simply not there.
I also tried a workaround like this:
test = requests.get('http://www.goldentigercasino.de/')
for link in BeautifulSoup(test.text, parse_only=SoupStrainer('a',{'href': not None})):
That works as wanted Except that it also returns the Doctype:
HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"
Which is causing also trouble for the same reasons as above.
My question: Why does hasattr always returns true and how can I fix that? And if there is no possibility with hasattr, how can i fix my workaround that its not returning the DOCTYPE?
Many Thanks and best regards!
hasattr()
is the wrong test; it tests if there is a a.href
attribute, and BeautifulSoup dynamically turns attributes into searches for children. HTML tag attributes are not translated into Python attributes.
Use dictionary-style testing instead; you loop over all elements which can include the DocType
instance, so I use getattr()
to not break on objects that don't have attributes:
if 'href' in getattr(link, 'attrs', {}):
You can also instruct SoupStrainer
to only match a
tags with a href
attribute by using href=True
as a keyword argument filter (not None
just means True
in any case):
for link in BeautifulSoup(test.text, parse_only=SoupStrainer('a', href=True)):
This still includes the HTML declaration of course; search for just a
links:
soup = BeautifulSoup(test.text, parse_only=SoupStrainer('a', href=True))
for link in soup.find_all('a'):
print link
来源:https://stackoverflow.com/questions/17943992/beautifulsoup-and-soupstrainer-for-getting-links-dont-work-with-hasattr-returni