[PP-main] Technical/implementation matters

[Joakim Ziegler]

On Mon, Mar 06, 2000 at 10:40:49AM +0930, Nick Lothian wrote:

>> Also, it's kind of messy to use RDF, since RDF is intended as a
>> descriptive,
>> not containing, format. In other words, to publish a news item, you need
>> to
>> use an RDF file to describe it, and another file which is the actual
>> content.
>> And that means we still need to find a format for that content, and it
>> can't
>> be HTML, it needs to be some XML DTD, since we're going to be marking up
>> in a
>> very abstract way.

> Yes, I agree with this - I'm not proposing we use RDF, simply use a single
> XML file similar to a RDF file, perhaps with links to other URLs  to get the
> actual content.

I'd like to see this embedded in the same file as the actual content, though.
It's a lot easier, and less susceptible to network 

>> So I propose to make an XML format that encapsulates the data you would
>> normally put in the RDF/RSS file (perhaps even by embedding directly,
>> using
>> XML namespaces), but we need a format for the actual data, and no such
>> format
>> exists.

> I think I agree with that. What do you mean by "a format for the actual
> data", though? Do you mean the formatting of the story or something like
> that?

Yes, at least it will need *a* format. Plain text is insufficient, you'll at
least need the standard trappings of the journalist trade, like boldface,
italics, etc., and also a way to specify links. Maybe a simple table syntax,
and a way to reference images that go with the story (possibly without
setting the position in the text, though, that should be up to the formatting
on the site side).

So we don't want full HTML, but we want something richer than plain text.
That means an XML DTD, and that means it might as well be in the same file as
the RDF-type stuff. Actually, that's quite efficient, since for shorter news
items, the metadata is likely to be at least as many bytes as the actual text.


>> The protocol can easily handle push and pull. Especially since it's a
>> matter of "push to me when I'm connected".

> So what if the client disconnects without informing the server it doesn't
> need a feed anymore? Does the server attempt to keep pushing? Or maybe
> attempt to push a number of times, and them stop?

You get a broken pipe. This is the same thing as with HTTP servers, if you
request a 100 MB file, and you drop the connection, the server notices, and
stops pushing. Exactly the same.


> Doesn't this make it extreamly vunrable to denial of service attacks?

No more than an HTTP server. Less, actually, since we're actually requiring
people to log in to the system to get data push.

-- 
Joakim Ziegler - simplemente r&d director - joakim at simplemente.net
 FIX sysop - free software coder - FIDEL & Conglomerate developer
      http://www.avmaria.com/ - http://www.simplemente.net/