Until now, it was not possible to substitute missing paths from e.g.
`https://cache.nixos.org` on a remote server when building on it using
the new `ssh-ng` protocol.
This is because every store implementation except legacy `ssh://`
ignores the substitution flag passed to `Store::queryValidPaths` while
the `legacy-ssh-store` substitutes the remote store using
`cmdQueryValidPaths` when the remote store is opened with `nix-store
--serve`.
This patch slightly modifies the daemon protocol to allow passing an
integer value suggesting whether to substitute missing paths during
`wopQueryValidPaths`. To implement this on the daemon-side, the
substitution logic from `nix-store --serve` has been moved into a
protected method named `Store::substitutePaths` which gets currently
called from `LocalStore::queryValidPaths` and `Store::queryValidPaths`
if `maybeSubstitute` is `true`.
Fixes#2770
Crucially this introduces BoehmGCStackAllocator, but it also
adds a bunch of wiring to avoid making libutil depend on bdw-gc.
Part of the solutions for #4178, #4200
This removes the extra-substituters and extra-sandbox-paths settings
and instead makes every array setting extensible by setting
"extra-<name> = <value>" in the configuration file or passing
"--<name> <value>" on the command line.
This makes it even clearer which of the two hashes was specified in the
nix files. Some may think that "wanted" and "got" is obvious, but:
"got" could mean "got in nix file" and "wanted" could mean "want to see in nix file".
Although the non-resolved derivation will never get a cache-hit (it
doesn't have an output path to query the cache for anyways), we might
get one on the resolved derivation.
This reverts commit 189e6f5e1d.
After some discussion, it seems better not to bump the major version
number since most of the new features since 2.3 are marked
experimental.
This is primarily useful if you're hacking simultaneously on a package
and one of its dependencies. E.g. if you're hacking on Hydra and Nix,
you would start a dev shell for Nix, and then a dev shell for Hydra as
follows:
$ nix develop \
--redirect .#hydraJobs.build.x86_64-linux.nix ~/Dev/nix/outputs/out \
--redirect .#hydraJobs.build.x86_64-linux.nix.dev ~/Dev/nix/outputs/dev
(This assumes hydraJobs.build.x86_64-linux has a passthru.nix
attribute. You can also use a store path.)
This causes all references in the environment to those store paths to
be rewritten to ~/Dev/nix/outputs/{out,dev}. Note: unfortunately, you
may need to set LD_LIBRARY_PATH=~/Dev/nix/outputs/out/lib because
Nixpkgs' ld-wrapper only adds -rpath entries for -L flags that point
to the Nix store.