[Python-Dev] Should urlencode() sort the query parameters (if they come from a dict)?

[Guido van Rossum]

On Sat, Aug 18, 2012 at 6:28 AM, Christian Heimes <lists at cheimes.de> wrote:
> Am 17.08.2012 21:27, schrieb Guido van Rossum:
>> I wonder if it wouldn't make sense to change urlencode() to generate
>> URLs that don't depend on the hash order, for all versions of Python
>> that support PYTHONHASHSEED? It seems a one-line fix:
>>
>>         query = query.items()
>>
>> with this:
>>
>>         query = sorted(query.items())
>>
>> This would not prevent breakage of unit tests, but it would make a
>> much simpler fix possible: simply sort the parameters in the URL.
>
> I vote -0. The issue can also be addressed with a small and simple
> helper function that wraps urlparse and compares the query parameter. Or
> you cann urlencode() with `sorted(qs.items)` instead of `qs` in the
> application.

Hm. That's actually a good point.

> The order of query string parameter is actually important for some
> applications, for example Zope, colander+deform and other form
> frameworks use the parameter order to group parameters.
>
> Therefore I propose that the query string is only sorted when the query
> is exactly a dict and not some subclass or class that has an items() method.
>
>     if type(query) is dict:
>         query = sorted(query.items())
>     else:
>         query = query.items()

That's already in the bug I filed. :-) I also added that the sort may
fail if the keys mix e.g. bytes and str (or int and str, for that
matter).

-- 
--Guido van Rossum (python.org/~guido)