bug#26201: hydra.gnu.org uses ‘guix publish’ for nars and narinfos

[ludo@gnu.org (Ludovic Courtès)]

ludo@gnu.org (Ludovic Courtès) skribis:

>   2. Produce a narinfo and corresponding nar the first time they are
>      requested.  So, the first time we receive “GET foo.narinfo”, return
>      404 and spawn a thread to compute foo.narinfo and foo.nar.  Return
>      200 only when both are ready.
>
>      The precomputed nar{,info}s would be kept in a cache and we could
>      make sure a narinfo and its nar have the same lifetime, which
>      addresses one of the problems we have.
>
>      pros: better HTTP latency and bandwidth
>      pros: allows us to add a Content-Length for nars
>      pros: helps keep narinfo/nar lifetime in sync
>      cons: doesn’t reduce load on hydra.gnu.org
>      cons: exposes inconsistency between the store contents and the HTTP
>            response (you may get 404 even if the thing is actually in
>            store), but maybe that’s not a problem

Implemented in commit 00753f7038234a0f5a79be3ec9ab949840a18743.

I’ll set up a test instance shortly.

Ludo’.