Commit graph

7 commits

Author SHA1 Message Date
Eelco Dolstra 6069b946ad
nix-store --serve: Support setting build-repeat
This allows Hydra to test whether builds are reproducible.
2016-12-06 17:19:22 +01:00
Eelco Dolstra 1abda8e173 nix-store --serve: Implement log size limit 2015-10-06 17:33:30 +02:00
Eelco Dolstra 1511aa9f48 Allow remote builds without sending the derivation closure
Previously, to build a derivation remotely, we had to copy the entire
closure of the .drv file to the remote machine, even though we only
need the top-level derivation. This is very wasteful: the closure can
contain thousands of store paths, and in some Hydra use cases, include
source paths that are very large (e.g. Git/Mercurial checkouts).

So now there is a new operation, StoreAPI::buildDerivation(), that
performs a build from an in-memory representation of a derivation
(BasicDerivation) rather than from a on-disk .drv file. The only files
that need to be in the Nix store are the sources of the derivation
(drv.inputSrcs), and the needed output paths of the dependencies (as
described by drv.inputDrvs). "nix-store --serve" exposes this
interface.

Note that this is a privileged operation, because you can construct a
derivation that builds any store path whatsoever. Fixing this will
require changing the hashing scheme (i.e., the output paths should be
computed from the other fields in BasicDerivation, allowing them to be
verified without access to other derivations). However, this would be
quite nice because it would allow .drv-free building (e.g. "nix-env
-i" wouldn't have to write any .drv files to disk).

Fixes #173.
2015-07-17 17:57:40 +02:00
Eelco Dolstra 03103c0a36 Implement nix-copy-closure --from via nix-store --serve 2014-07-24 16:19:41 +02:00
Eelco Dolstra a5c6347ff0 build-remote.pl: Use ‘nix-store --serve’ on the remote side
This makes things more efficient (we don't need to use an SSH master
connection, and we only start a single remote process) and gets rid of
locking issues (the remote nix-store process will keep inputs and
outputs locked as long as they're needed).

It also makes it more or less secure to connect directly to the root
account on the build machine, using a forced command
(e.g. ‘command="nix-store --serve --write"’). This bypasses the Nix
daemon and is therefore more efficient.

Also, don't call nix-store to import the output paths.
2014-07-11 16:22:24 +02:00
Eelco Dolstra 04170d06bf nix-copy-closure: Fix race condition
There is a long-standing race condition when copying a closure to a
remote machine, particularly affecting build-remote.pl: the client
first asks the remote machine which paths it already has, then copies
over the missing paths. If the garbage collector kicks in on the
remote machine between the first and second step, the already-present
paths may be deleted. The missing paths may then refer to deleted
paths, causing nix-copy-closure to fail. The client now performs both
steps using a single remote Nix call (using ‘nix-store --serve’),
locking all paths in the closure while querying.

I changed the --serve protocol a bit (getting rid of QueryCommand), so
this breaks the SSH substituter from older versions. But it was marked
experimental anyway.

Fixes #141.
2014-07-10 11:58:59 +02:00
Shea Levy c89d6b9b63 nix-store --serve: Use a versioned protocol
Signed-off-by: Shea Levy <shea@shealevy.com>
2014-02-10 07:43:13 -05:00