Re: [Httplib2-discuss] httplib2 should provide custom exceptions for httplib failures

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On 7 Dec 2006, at 12:01, Sam Ruby wrote:
> What's bad (IMO) is that httplib2, like its predecessor does both.   
> Do I get a 408 or a socket.timeout?  Actually, you can get both.
>
> Since status codes are not going away, I would suggest mapping more  
> exceptions to status codes, and documenting the few (if any)  
> remaining "expected exceptions".

It's interesting to note the difference here between Python's urllib  
and urllib2 modules:

 >>> import urllib, urllib2
 >>> urllib.urlopen('http://simonwillison.net/nothing-here').read()
'<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">\n<html><head> 
\n<title>404 Not Found</title>\n</head><body>\n<h1>Not Found</h1> 
\n<p>The requested URL /nothing-here was not found on this server.</p> 
\n</body></html>\n'

 >>> urllib2.urlopen('http://simonwillison.net/nothing-here').read()
Traceback (most recent call last):
   ...
   File "/Library/Frameworks/Python.framework/Versions/2.5/lib/ 
python2.5/urllib2.py", line 499, in http_error_default
     raise HTTPError(req.get_full_url(), code, msg, hdrs, fp)
urllib2.HTTPError: HTTP Error 404: Not Found
 >>>

Whether or not this is desired behaviour depends very much on what  
you are trying to do.

One solution might be for httplib2 to have two request methods - one  
that raises exceptions and one that returns the document with the  
non-200 status code. It would be nice if Python had a standard idiom  
or naming convention for pairs of methods like this, but it's not  
something I've seen anywhere. There might be a good reason for that  
of course.

Cheers,

Simon