[Yum-devel] [PATCH] remove RPMDBPackageSack.installed()

[Tim Lauridsen]

Panu Matilainen wrote:
> On Thu, 4 Oct 2007, Tim Lauridsen wrote:
>
>> Florian Festi wrote:
>>> Hi!
>>>
>>> While creating the new test frame work I came across several minor 
>>> issues. One problem is the existence of the 
>>> RPMDBPackageSack.installed() method. It is currently only supported 
>>> by the RPMDBPackageSack class. This doesn't allow to replace the 
>>> rpmdb with an inmemory PackageSack. Seth already rejected the idea 
>>> of just moving the method to the base class as "installed" doesn't 
>>> make any sense for non RpmDB sacks.
>>>
>>> As I really dislike inconsistent APIs I'd like to suggest to just 
>>> remove the usage of that method from the code. There are just 7 
>>> places in yum and one place in yum-utils where it is used and it is 
>>> nothing more than a tiny convenience wrapper. In fact it can be 
>>> replaced quite easily by .searchNevra() - one of our work horse 
>>> methods. The attached patches remove the usage of the method and add 
>>> an deprecation warning (feel free to ignore that if we want to keep 
>>> the method).
>>>
>>> Florian
>>>
>>> PS: The patch also fixes a small issue when running without 
>>> repositories which simplifies setting up the test cases.
>>> ------------------------------------------------------------------------ 
>>>
>>>
>>> _______________________________________________
>>> Yum-devel mailing list
>>> > Yum-devel at linux.duke.edu
>>> https://lists.dulug.duke.edu/mailman/listinfo/yum-devel
>> RPMDBPackageSack.installed() make the code look better and make it 
>> easier to understand.
>>
>> self.rpmdb.installed(po)
>>
>> Look much better then self.rpmdb.searchNevra(po.name, po.epoch, 
>> po.version, po.release, po.arch)
>>
>> Removing the installed() method is a API breakage and there is other 
>> API users out there (yumex, pirut, pungi, revisor, PackageKit etc)
>>
>> and api users (like me) hate this kind of breakage :)
>>
>> from an API users point of view, he/she want to simple and easy to 
>> use API, and in this case 'installed(po)' is much better than 
>> 'self.rpmdb.searchNevra(n,e,v,r,a)', there have also been done a lot 
>> of work to replace n,e,v,r,a tuples with po object, this is a step 
>> backwards.
>
> The problem with installed() is just that it's the wrong term for this 
> - make it exists() and it'll make sense for all the package sack 
> types. Whether a package is installed or not is just a question 
> whether it exists in rpmdb or not, if you want to keep API compat just 
> make rpmdb.installed() a wrapper for exists().
Sound like a good idea, it still keeps the api simple.
>
> Somewhat related, IMO the installed() method belongs to the package, 
> not sack object. So something like
>
> for pkg in installable:
>     if self.rpmdb.installed(po=pkg):
>        # do stuff
>
> would become
>
> for pkg in installable:
>     if pkg.installed():
>        # do stuff
>
> ..but that's another story, dunno how feasible it'd be within yum 
> currently (sorry I haven't been paying that much attention lately)
Sound like a great idea, but can be tricky to implement.
a YumInstalledPackage know it is installed, but a YumAvailablePackage 
dont know if it is installed, I know it is available in a repo, but it 
dont know if it is installed on the system.

Tim