[darcs-users] GSoC: network optimisation vs cache vs library?

[Max Battcher]

On 4/18/2010 22:56, Zooko O'Whielacronx wrote:
> In this case we have a robots.txt exclusion file and the only times
> the HTTP GETs are called (as far as I've noticed) is when a user wants
> to see that page.

It's not usually a good practice to rely on robots.txt, either. There 
have been many robots that have ignored such files, and there will 
continue to be. (Plus, never assume that malicious users don't exist.)

Plus, once you have it cached, some of the pages are presumably just the 
sort of thing you might want to have indexed by one search engine or 
another... (Source Code search engines are getting increasingly 
interesting.)

>> I've made the suggestion to Lele that Trac+Darcs, in the case of "hard operations" such as this one, should make use of a processing queue
>
> This would be a change to Trac -- it can't really be done in a
> revision control plugin for Trac. Trac assumes that all calls to
> revision control tool to browse history will return quickly.

The point of a processing queue would be to always return back to Trac 
quickly (thus making the plugin work more along Trac's assumption), but 
in some cases with a "Not currently in cache" temporary page of one sort 
or another while the real operation happens in the background. I don't 
know Trac's architecture, but presumably that shouldn't require major 
changes to Trac. (Theoretically, its all very possible in Python, 
regardless of where you are in an abstraction stack.)

Certainly it would be a strategy that could be promoted into Trac proper 
so that other plugins could take advantage of it. However, there should 
be few obstacles stopping the Trac+Darcs plugin from building something 
along these lines itself until such time as Trac is sufficiently ready 
to adopt something similar at the "platform level".

But I presume Lele would be the judge of how feasible such a project 
would be and for potentially lobbying (or patching) Trac itself if it 
should be a feature that would benefit other plugins.

--
--Max Battcher--
http://worldmaker.net