ca-derivations support

[thufschmitt]

Add a /realisations endpoint to support content-addressed derivations.

This required updating Nix (currently using a custom branch even) to access a new queryRawRealisation perl function that’s needed for that.

As part of this, I also had to upgrade nixpkgs to match the one used by the Nix flake, which caused an update of perl which in turn broke things:

• For some reason, the /nix-cache-info endpoint doesn’t properly interpolate the store dir anymore
• The narinfo files now have an extra newline at the end, which breaks the Nix parser

I’ll try to build everything with the old nixpkgs, seeing whether that fixes the issues for the time being

Fix #20

/cc @Mic92 @zseri @SuperSandro2000

[Mic92]

I also started adding CI here: https://github.com/edolstra/nix-serve/pull/22

[thufschmitt]

Just saw the rewrite at https://github.com/Mic92/nix-serve , which seems to be a much nicer alternative. @Mic92 do you need any help with it?

[Mic92]

I am not so happy with the performance of the used http server library yet: https://github.com/yhirose/cpp-httplib/issues/1023 It's probably faster than the current perl implementation... I am currently rewriting this using libh2o, which gives me also http2 - none of the c++ libraries I found support chunking, which is needed for large nars.

[SuperSandro2000]

Ported this to hydra here https://github.com/SuperSandro2000/hydra/commit/9e528b2faee8a2bcdb25290ff4fcbc0423c9fbd2

@thufschmitt could you finish that anyway just for completeness?

[Mic92]

I am not so happy with the performance of the used http server library yet: yhirose/cpp-httplib#1023 It's probably faster than the current perl implementation... I am currently rewriting this using libh2o, which gives me also http2 - none of the c++ libraries I found support chunking, which is needed for large nars.

These days I am just using harmonia: https://github.com/nix-community/harmonia/