Re: pgcrypto: PGP armor headers

On 9/30/14 4:37 PM, Heikki Linnakangas wrote:
> On 09/29/2014 05:38 PM, Marko Tiikkaja wrote:
>> Maybe I just suck at $SEARCH_ENGINE, but extracting armor headers
>> programmatically doesn't seem to be very popular.  I could only find one
>> example, which returned the last instance of the key.  But that seemed
>> to be more an accident than anything else; it wasn't documented and the
>> source code didn't say anything about it.  I also think that's the worst
>> behaviour.  If we can't agree on concatenation, I'd rather see an error.
>
> May I ask you why you wrote this patch? What are you doing with the headers?

We're sending arbitrary messages between systems over HTTP(S), and a 
special header is used to tell the recipient system what type of message 
it is.  The message types are specific to the domain, but you can think 
of them to be roughly equivalent to MIME types.

If what you're trying to get a sense of is why I'd prefer to see 
concatenation, I can't really help you.  For our use case (and perhaps 
for everyone else as well) it would actually make more sense to throw an 
error if pgp_armor_header() is used on a key which appears more than 
once.  The concatenation behaviour was an attempt at a "one size fits 
all" interface, but now that we're going to also have a 
pgp_armor_headers() function for users to implement the behaviour they 
want themselves, there's no real reason to try and guess what everyone 
wants.  I think I'd prefer to see an ERROR in this case now.


.marko