Jeff Johnson:
>>> Header tags _ARE_ ordered, just the collation isn't
>>> what no brainer conversions into native data types
>>> are implementing.
> And the collation is integer numeric based on tag numbers.
Okay. Does this tag ordering need to be preserved ?
If so, we should change the --yaml and --json now.
> There's a s superficial and a deep answer here.
>
> SOmehow it needs to be indicated that header speawage
> is _NOT_ random, but rather carefully sorted in many
> ways.
All the sequences/arrays maintain their sort order,
but the mappings/objects do not (they're unordered)
> The "LSB packaging standard" totally blew it with respect to
> tag ordering.
>
> And the spewage -- if not carefully controlled -- will be useless
> for RPM itself, whose task is to import/export through speawage
> into a "header" blob.
If spewage is to preserve tag ordering, then the
currently used markup/schema needs to be changed.
From:
{
Tag1: Value1,
Tag2: Value2,
Tag3: Value3
}
To:
[
{ Tag1: Value1 },
{ Tag2: Value2 },
{ Tag3: Value3 }
]
This will make it slightly trickier to handle,
but it will preserve the order of the keys/tags.
>>> But it hardly matters with spewage, fewer tokens to ask
>>> about KISS simplicity trumps everything else in FL/OSS.
>>
>> For the YAML and JSON formats, it's easier unordered.
>
> Easier for whom? Lusers who don't undertsand what
> "canoniocally represented plaintext" actually means?
>
> Or why sorted data can be accessed in logN not linear time?
Easier formats, i.e. not needing nested structures ?
But if it's needed, it's needed. I thought it wasn't.
>> And I think the XML would need a DTD, to do ordering ?
>>
>
> No idea what XML "needs". I do know from rpmrepo that
> its _IMPOSSIBLE_ to be bit for bit compatible because
> tag data is being run through a python dict which
> _DESTROYS_ the ordering of the original data.
Right. The same goes for using a mongo document iirc ?
>> i.e. XML does ordering now, but I think a parser is
>> "free" to reorder the elements without invalidating ?
>>
>
> Please note that I'm disagreeing with your patch whatsoever.
>
> But somehow and somewhere it needs to be hinted to all
> the "spewage suckers" that there are most definitely
> performance and interoperability wins by establishing
> a sorted and canonical ordering on the spewage items.
>
> Yes I know how to use qsort(3) wherever needed. I'm enetrested
> in proper spewage specification on which it becomes feasible
> to define digests/signatures and simplify interoperability
> and implementations. And most definitely I'm not holding my breath
> waiting for FedEx to ship me a pony ...
If metadata must be sorted, it should be specified
and required by any export/import (in any format).
Was under the impression that it was only "needed"
for arrays like Requires/Files, but probably wrong.
--anders
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