Help for urllib error : 'no host given'

[Steve Holden]

<Patrick.Bussi at space.alcatel.fr> wrote...
>
> Hello,
>
> I cannot understand why I get the following error.
>
> 1) Here is an extract of the web page content I want to parse :
> -------------
> function RedirectPage()
> {
> document.location ="http://www.nicewebsite.com";
> }
> -------------
>
>
> 2) Here is the program I use to extract the URL to which I need to
redirect my
> browsing (ugly, I agree)
> -------------
> q=re.compile("document.location =.*")
> t2=q.search(f3)  # f3 contains the full string of the web page
> b= t2.group()
> q1=re.compile('[^document.location ="].*[^";]')
> t4=q1.search(b)
> redirectURL=t4.group()
> f4=urllib.urlopen(redirectURL).read()
> --------------
> The program successfully extracts the name of the Url. I can print the
exact
> text "http://www.nicewebsite.com" (without the quotes).
>
>
> 3) And finally here is the traceback I get :
> -----------------------
> Traceback (innermost last):
>   File "./MyProgram", line 157, in ?
>     f4=urllib.urlopen(redirectURL).read()
>   File "/usr/lib/python1.5/urllib.py", line 59, in urlopen
>     return _urlopener.open(url)
>   File "/usr/lib/python1.5/urllib.py", line 157, in open
>     return getattr(self, name)(url)
>   File "/usr/lib/python1.5/urllib.py", line 272, in open_http
>     return self.http_error(url, fp, errcode, errmsg, headers)
>   File "/usr/lib/python1.5/urllib.py", line 285, in http_error
>     result = method(url, fp, errcode, errmsg, headers)
>   File "/usr/lib/python1.5/urllib.py", line 456, in http_error_302
>     return self.open(newurl, data)
>   File "/usr/lib/python1.5/urllib.py", line 157, in open
>     return getattr(self, name)(url)
>   File "/usr/lib/python1.5/urllib.py", line 247, in open_http
>     if not host: raise IOError, ('http error', 'no host given')
> IOError: [Errno http error] no host given
> ---------------------------
>
>
> For professional reason, I had to change the web site name above. Could in
any
> case urllib() be sensitive to the content of the requested URL (full of
"&"
> chars) ?
>
> Thank you for any help.
>
Patrick:

Maybe it's the URL:

>>> import re, urllib
>>> q=re.compile("document.location =.*")
>>> t2=q.search(f3)
>>> b= t2.group()
>>> q1=re.compile('[^document.location ="].*[^";]')
>>> t4=q1.search(b)
>>> redirectURL=t4.group()
>>> redirectURL
'http://www.nicewebsite.com'
>>> f4=urllib.urlopen(redirectURL).read()
>>> f4
'<!-- frames -->\015\012<frameset  rows="50%,75" border="0"
framespacing="0"> \015\012  <frame name="destframe"
src="http://futuresite.register.com/futuresite.shtml" marginwidth="0"
marginheight="0" scrolling="auto" frameborder="0">\015\012  <frame
src="http://futuresite.register.com/us?www.nicewebsite.com" name="bottom"
frameborder="0" scrolling="NO" marginwidth="0" marginheight="0"
noresize>\015\012</frameset><noframes></noframes>\015\012'
>>>

Seems to work fine with the URL you gave, so have you checked that the URL
you are using really is a valid one? It looks like you might have missed a
slash out:

>>> urllib.urlopen("http:/www.nosuchsitehere.com")
Traceback (innermost last):
  File "<interactive input>", line 1, in ?
  File "d:\python20\lib\urllib.py", line 61, in urlopen
    return _urlopener.open(url)
  File "d:\python20\lib\urllib.py", line 166, in open
    return getattr(self, name)(url)
  File "d:\python20\lib\urllib.py", line 261, in open_http
    if not host: raise IOError, ('http error', 'no host given')
IOError: [Errno http error] no host given

Hope you track it down.

regards
 Steve