When using urllib2.urlopen to fetch the source code of websites like this one, I decode the bytes and extract the code marked as applet using beautifulsoup. The code snippet may contain lines such as:
<param name="G_00" value="espacio='E1' tipo='macro' expresión='dinamica/resorte'">
I am specifically interested in capturing all values of "expresión=" within the code that are under the attribute tipo="macro" (specifically dinamica/resorte and dinamica/masa).
Using beautifulsoup, I locate these lines as tags with tipo='macro'. To be succinct, I focus on extracting the content following expresión=:
key_macro = ['expresión=', 'expresion=', 'expresión='....] # this presents a potential issue.
for y in key_macro:
if string.find(tag, y) != -1:
mexpression = r"%s'([\w\./]+)'" % y
mpatron = re.compile(mexpression)
mresult = mpatron.search(tag['value'])
if mresult:
macroslist.append(mresult.group(1))
wexpression = r"%s'([\w/]+)'" % y
wpatron = re.compile(wexpression)
wresult = wpatron.search(tag['value'])
if wresult:
macroslist.append(wresult.group())
The challenge: While #1 retrieves the .txt file successfully when available, #2 which seeks word/word patterns often fails to find instances like dinamica/resorte. Is there an issue with my regular expressions? How can I effectively specify word/word in a regex?
I attempted searching using beautifulsoup but encountered difficulty due to 'macro' being contained within the value. Although re + search seems promising (...when encountering formats like dinamica/resorte.txt, where #1 functions), it struggles without the file extension.
Thank you for your assistance.