Rather than having them plain strings scattered through the whole
codebase, create an enum containing all the known experimental features.
This means that
- Nix can now `warn` when an unkwown experimental feature is passed
(making it much nicer to spot typos and spot deprecated features)
- It’s now easy to remove a feature altogether (once the feature isn’t
experimental anymore or is dropped) by just removing the field for the
enum and letting the compiler point us to all the now invalid usages
of it.
I had started the trend of doing `std::visit` by value (because a type
error once mislead me into thinking that was the only form that
existed). While the optomizer in principle should be able to deal with
extra coppying or extra indirection once the lambdas inlined, sticking
with by reference is the conventional default. I hope this might even
improve performance.
This adds a new store operation 'addMultipleToStore' that reads a
number of NARs and ValidPathInfos from a Source, allowing any number
of store paths to be copied in a single call. This is much faster on
high-latency links when copying a lot of small files, like .drv
closures.
For example, on a connection with an 50 ms delay:
Before:
$ nix copy --to 'unix:///tmp/proxy-socket?root=/tmp/dest-chroot' \
/nix/store/90jjw94xiyg5drj70whm9yll6xjj0ca9-hello-2.10.drv \
--derivation --no-check-sigs
real 0m57.868s
user 0m0.103s
sys 0m0.056s
After:
real 0m0.690s
user 0m0.017s
sys 0m0.011s
Align all the worker protocol with `buildDerivation` which inlines the
realisations as one opaque json blob.
That way we don’t have to bother changing the remote store protocol
when the definition of `Realisation` changes, as long as we keep the
json backwards-compatible
I guess I misunderstood John's initial explanation about why wildcards
for outputs are sent to older stores[1]. My `nix-daemon` from 2021-03-26
also has version 1.29, but misses the wildcard[2]. So bumping seems to
be the right call.
[1] https://github.com/NixOS/nix/pull/4759#issuecomment-830812464
[2] 255d145ba7
This avoids an ambiguity where the `StorePathWithOutputs { drvPath, {}
}` could mean "build `brvPath`" or "substitute `drvPath`" depending on
context.
It also brings the internals closer in line to the new CLI, by
generalizing the `Buildable` type is used there and makes that
distinction already.
In doing so, relegate `StorePathWithOutputs` to being a type just for
backwards compatibility (CLI and RPC).
These are by no means part of the notion of a store, but rather are
things that happen to use stores. (Or put another way, there's no way
we'd make them virtual methods any time soon.) It's better to move them
out of that too-big class then.
Also, this helps us remove StorePathWithOutputs from the Store interface
altogether next commit.
A few versioning mistakes were corrected:
- In 27b5747ca7, Daemon protocol had some
version `>= 0xc` that should have been `>= 0x1c`, or `28` since the
other conditions used decimal.
- In a2b69660a9, legacy SSH gated new CAS
info on version 6, but version 5 in the server. It is now 6
everywhere.
Additionally, legacy ssh was sending over more metadata than the daemon
one was. The daemon now sends that data too.
CC @regnat
Co-authored-by: Cole Helbling <cole.e.helbling@outlook.com>
For each known realisation, store:
- its output
- its output path
This comes with a set of needed changes:
- New `realisations` module declaring the types needed for describing
these mappings
- New `Store::registerDrvOutput` method registering all the needed informations
about a derivation output (also replaces `LocalStore::linkDeriverToPath`)
- new `Store::queryRealisation` method to retrieve the informations for a
derivations
This introcudes some redundancy on the remote-store side between
`wopQueryDerivationOutputMap` and `wopQueryRealisation`.
However we might need to keep both (regardless of backwards compat)
because we sometimes need to get some infos for all the outputs of a
derivation (where `wopQueryDerivationOutputMap` is handy), but all the
stores can't implement it − because listing all the outputs of a
derivation isn't really possible for binary caches where the server
doesn't allow to list a directory.
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
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.
In particular, this means that derivations can output derivations. But
that ramification isn't (yet!) useful as we would want, since there is
no way to have a dependent derivation that is itself a dependent
derivation.
Include a long comment explaining the policy. Perhaps this can be moved
to the manual at some point in the future.
Also bump the daemon protocol minor version, so clients can tell whether
`wopBuildDerivation` supports trustless CA derivation building. I hope
to take advantage of this in a follow-up PR to support trustless remote
building with the minimal sending of derivation closures.
Before, processConnection wanted to know a user name and user id, and
`nix-daemon --stdio`, when it isn't proxying to an underlying daemon,
would just assume "root" and 0. But `nix-daemon --stdio` (no proxying)
shouldn't make guesses about who holds the other end of its standard
streams.
Now processConnection takes an "auth hook", so `nix-daemon` can provide
the appropriate policy and daemon.cc doesn't need to know or care what
it is.
Since 6185d25e52, this was very
latency-bound since it required a round-trip for every 32 KiB. So for
example copying a 514 MiB closure over a virtual ethernet device with
a articial delay of just 1 ms took 343s. Now it takes 2.7s.
Fixes#3372.
This assumption is broken by CA derivations. Making a PR now to do the
breaking daemon change as soon as possible (if it is already too late,
we can bump protocol intead).
Maximilian Bosch
Robert Hensing