[PATCH mock] Enhancements of the config_opts['macros'] handling

[Paul Howarth]

Michael E Brown wrote:
> On Mon, May 07, 2007 at 08:13:35PM +0200, Enrico Scholz wrote:
>> Michael E Brown <Michael_E_Brown at dell.com> writes:
>>
>>>> +    def _expand_macro_string(self, macros):
>>>> +        res = []
>>>> +        if isinstance(macros, dict):
>>>> +            for (key,v) in macros.items():
>>>> +                res.append('%s\t%s' % (key,v))
>>>> +        elif isinstance(macros,  basestring):
>>>> +            res = [macros]
>>>> +        else:
>>>> +            for v in macros:
>>>> +                res.append(self._expand_macro_string(v))
>>>> +
>>>> +        return '\n'.join(res) + '\n'
>>> How does this affect the ability to overwrite config from a config file
>>> higher in the heirarchy?
>> You can write e.g.
>>
>> | -- defaults.cfg --
>> | config_opts['macros'] = "%foo 1"
> 
> If something like this goes in, I expect that to become the defualt for
> everything we ship. In this case:
>     - setup_default_config_opts() would set up defaults using new format.
>     - defaults.cfg probably wouldnt have this option
>     - get rid of the recursive processing. If the option is a string,
>       return it. If it is not a string, use dict processing model.
> 
> This means:
>     - everything we ship uses new format
>     - old users of this option still work but are encouraged to switch
>       to the new format
> 
> Additionally:
>     - We need a way to override options in subconfig files.
> 
> Suggestion:
>     - We should use a dict for the option. If the hash value is None, or
>       some variation thereof, dont
> 
> defaults.conf:
>   config_opts['macros'] = { '%foo': "xyz", "%bar": "123", "%baz": "quux" }
> 
> my-root.conf:  # completely override all defaults
>   config_opts['macros'] = { "%someopt": "someval" }
> 
> my-root.conf:  # only override some
>   config_opts['macros']['%foo'] = "myvalue"
>   config_opts['macros']['%bar'] = None      #dont output this in final
>                                             #  .rpmmacros
> 
> --
> Michael
> 
> 
> 
>> | 
>> | -- my-root.cfg ==
>> | config_opts['macros'] = [
>> |   config_opts['macros'],
>> |   {
>> |     '%bar' : 2
>> |   }
>> | ]
>>
>> Overwriting is not possible/easy when we want to retain backward
>> compatibility.  When implemented from scratch, I would have implemented
>> this option completely as a dictionary (I do not think that order of
>> macros is for much interest).
>>
>>
>>>> +
>>>>      def _build_dir_setup(self):
>>>>          # purge the builddir, if it exists
>>>>          bd_out = '%s%s' % (self.rootdir, self.builddir)
>>>> @@ -788,8 +801,12 @@ class Root:
>>>>          macrofile_out = '%s%s/.rpmmacros' % (self.rootdir, self.homedir)
>>>>          if not os.path.exists(macrofile_out):
>>>>              rpmmacros = open(macrofile_out, 'w')
>>>> -            self.config['macros'] = self.config['macros'] + "\n%%_rpmlock_path	%s/var/lib/rpm/__db.000" % self.basedir
>>>> -            rpmmacros.write(self.config['macros'])
>>>> +
>>>> +            rpmmacros.write(self._expand_macro_string(self.config['macros']))
>>>> +            rpmmacros.write(self._expand_macro_string(
>>>> +                {"%_rpmlock_path" : "%s/var/lib/rpm/__db.000" % self.basedir}
>>>> +                ))
>>> This should go into the default config section, rather than hidden
>>> here.
>> I just rewrote this hunk of code. In a later version of my mock
>> modifications I removed this completely and replaced it by bind-mounting
>> the chrooted /var/lib/rpm directory into toplevel /var/lib/rpm.
>>
>>
>>> You need to convert the setup functions to use the new format by
>>> default, as well as any existing config file references in the
>>> default supplied configs.
>> See above for statement regarding backward compatibility; as long as
>> you do not change the default string-type, old/existing configurations
>> should still work.
>>
>> When defaults would be dictionaries or vectors, overwriting can fail
>> when people append an string.

Would it be possible to move creation of the macros file in the chroot 
to a point after the unpacking of an autocache cache? That would make it 
possible to use the same root (and cache) with configurations that 
differ only in macro values, which would save a lot of disk space for 
builders serving multiple repos (with different vendor/packager etc. 
macros).

Paul.