[Kolab-devel] Kolab 3.0: Mime Message Storage

[Thomas Brüderli]

Christian Mollekopf wrote:
>> First the encoding of the attachment is restricted to quoted-printable,
>> then the encoding of the XML attachment itself is set to utf-8.
>>
>> Honestly, mail clients require some level of compatibility already,
>> including a variety of encodings, such as iso-8859-1 or what is it
>> again, and it doesn't really seem impossible to just allow "whatever is
>> most convenient for the client writing it out".
>>
>> That is to say, libkolabmime / libkolab could of course just only ever
>> writing out quoted-printable. That's not the problem. I just think it's
>> best to not restrict what anything else might write out and have
>> libkolabmime / libkolab act accordingly upon reading the MIME attachment
>> - even though part of the exercise is to have "our clients" use
>> libkolab*.
>>
> 
> My point is, that if we allow *any* encoding, we have to support *any* 
> encoding in libkolab, and so does every other kolab client, which is in fact 
> impossible, unless there are some restrictions on the allowed encodings in the 
> MIME RFC. Given that a kolab client needs to make that decision anyways (in 
> which encoding to write out the xml), I don't see why it couldn't just use 
> quoted-printable, unless the given platform would indeed lack an 
> implementation of quoted-printable and implementing it would be too 
> cumbersome, which is unlikely given its simplicity. So overall I just see 
> allowing multiple encodings complicating matters without any benefits in 
> return.
> 
> I do see your argument about using utf-8 for the xml and then using quoted 
> printable to encode it again. We can allow utf-8 and quoted printable, if you 
> think it's worth the extra effort, but I'm really not in favor of allowing just 
> everything, because that just means we have to implement every encoding some 
> client implements because we don't comply to our own spec otherwise.

I'd also vote to allow 8bit (raw) encodings for the xml part. The charset
is specified to by UTF-8 by the format spec and all email servers, proxies
and clients nowadays should be able to handle and transfer such parts
without messing up their contents. I don't see the need for encoding the
xml part in quoted-printable either.

~Thomas