On 9.10.2014 09:27, Jan Zelený wrote:
On 9. 10. 2014 at 08:57:42, Ralf Corsepius wrote:
> On 10/09/2014 08:41 AM, Petr Spacek wrote:
>> On 8.10.2014 23:04, Haïkel wrote:
>>> 2014-10-08 20:31 GMT+02:00 Kevin Fenzi <kevin(a)scrye.com>:
>>>> Greetings.
>>>>
>>>> This F21 change:
>>>>
http://fedoraproject.org//wiki/Changes/RPM-4.12
>>>>
>>>> has brought us 'weak dependencies', namely:
>>>>
>>>> Recommends, Suggests, Supplements and Enhances
>>>>
>>>> Rpm in f21 and rawhide sees these in spec files and builds fine with
>>>> them. createrepo in those branches also exports this into the metadata.
>>>>
>>>> yum however doesn't do anything with that information.
>>>> dnf does (although it's not clear to me what exactly it does do, so
>>>> input from dnf maintainers would be great).
>>>>
>>>> There's 4 packages that are already using these weak deps, but our
>>>> default package manager (yum) doesn't understand them. People
>>>> installing via yum and installing via dnf will see different behavior.
>>>>
>>>> I filed a fesco ticket to ask that we ask maintainers to please not add
>>>> these until we have guidelines and our default package manager
supports
>>>> this information:
https://fedorahosted.org/fesco/ticket/1353
>>>>
>>>> FESCo asked me to post here and see what folks think.
>>>>
>>>> Should we just ask folks not to use these for now (honor system).
>>>>
>>>> Should we add a check to redhat-rpm-macros to check packages and
fail
>>>> the build if they use these tags (for now).
>>>>
>>>> Should we just not care that people will see different behavior and
>>>> leave it up to maintainers?
>>>>
>>>> Or should we do something else?
>>>
>>> Since our default package manager does not understand them, it's
>>> harmless to leave it up to the maintainers.
>>> Most importantly, we need to update packaging guidelines to explain
>>> what are the semantic differences between these different tags. But
>>> that's a minor update.
>>>
>>> Before dnf gets promoted as the default package manager, it would be
>>> interesting to do some widespread testing.
>>>
>>> 1. document dnf behavior with weak dependencies and related
>>> configuration options
>>> 2. let people experiment and provide feedbacks
>>> 3. based on feedbacks either propose guidelines or status quo if
>>> that's ok
>>
>> I agree with Haïkel.
>
> I do not.
I agree with Haikel and Petr, we have a great opportunity to test this and see
how it works.
>> Why should we ban weak dependencies if they really
>> do nothing in YUM?
>
> We need a precise and detailed functional description about what these
> "weak dependencies" are supposed to do.
Do you mean something like this?
http://rpm.org/wiki/PackagerDocs/Dependencies
It would be nice if words "weak dependencies" at
http://rpm.org/wiki/Releases/4.12.0
linked to
http://rpm.org/wiki/PackagerDocs/Dependencies#Weakdependencies
Jan, do you have rights to add the link to the
rpm.org wiki? I don't have
account myself ...
Petr^2 Spacek
> Also, we would need a precise and detailed description of how
weak deps
> are seen by non-weak-deps aware programs.
They are ignored (as demonstrated on the yum example), there is nothing else
to it :-)
Thanks
Jan