Reputation: 15770
I am writing a script to read a web page, and build a database of links that matches a certain criteria. Right now I am stuck with lxml and understanding how to grab all the <a href>
's from the html...
result = self._openurl(self.mainurl)
content = result.read()
html = lxml.html.fromstring(content)
print lxml.html.find_rel_links(html,'href')
Upvotes: 10
Views: 16140
Reputation: 1205
You can use this method:
from urllib.parse import urljoin, urlparse
from lxml import html as lh
class Crawler:
def __init__(self, start_url):
self.start_url = start_url
self.base_url = f'{urlparse(self.start_url).scheme}://{urlparse(self.start_url).netloc}'
self.visited_urls = set()
def fetch_urls(self, html):
urls = []
dom = lh.fromstring(html)
for href in dom.xpath('//a/@href'):
url = urljoin(self.base_url, href)
if url not in self.visited_urls and url.startswith(self.base_url):
urls.append(url)
return urls
Upvotes: 1
Reputation: 778
With iterlinks
, lxml provides an excellent function for this task.
This yields (element, attribute, link, pos) for every link [...] in an action, archive, background, cite, classid, codebase, data, href, longdesc, profile, src, usemap, dynsrc, or lowsrc attribute.
Upvotes: 5
Reputation: 373
I want to provide an alternative lxml-based solution.
The solution uses the function provided in lxml.cssselect
import urllib
import lxml.html
from lxml.cssselect import CSSSelector
connection = urllib.urlopen('http://www.yourTargetURL/')
dom = lxml.html.fromstring(connection.read())
selAnchor = CSSSelector('a')
foundElements = selAnchor(dom)
print [e.get('href') for e in foundElements]
Upvotes: 2
Reputation: 363707
Use XPath. Something like (can't test from here):
urls = html.xpath('//a/@href')
Upvotes: 15