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
This is needed to push the adoption of structured attrs[1] forward. It's
now checked if a `__json` exists in the environment-map of the derivation
to be openend in a `nix-shell`.
Derivations with structured attributes enabled also make use of a file
named `.attrs.json` containing every environment variable represented as
JSON which is useful for e.g. `exportReferencesGraph`[2]. To
provide an environment similar to the build sandbox, `nix-shell` now
adds a `.attrs.json` to `cwd` (which is mostly equal to the one in the
build sandbox) and removes it using an exit hook when closing the shell.
To avoid leaking internals of the build-process to the `nix-shell`, the
entire logic to generate JSON and shell code for structured attrs was
moved into the `ParsedDerivation` class.
[1] https://nixos.mayflower.consulting/blog/2020/01/20/structured-attrs/
[2] https://nixos.org/manual/nix/unstable/expressions/advanced-attributes.html#advanced-attributes
Make ca-derivations require a `ca-derivations` machine feature, and
ca-aware builders expose it.
That way, a network of builders can mix ca-aware and non-ca-aware
machines, and the scheduler will send them in the right place.
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).
Once a build is done, get back to the original derivation, and register
all the newly built outputs for this derivation.
This allows Nix to work properly with derivations that don't have all
their build inputs available − thus allowing garbage collection and
(once it's implemented) binary substitution
Don't only show the name of the output, but also the derivation to which
this output belongs (as otherwise it's very hard to track back what went
wrong)
PRs #4370 and #4348 had a bad interaction in that the second broke the fist
one in a not trivial way.
The issue was that since #4348 the logic for detecting whether a
derivation output is already built requires some logic that was specific
to the `LocalStore`.
It happens though that most of this logic could be upstreamed to any `Store`,
which is what this commit does.
`buildPaths` can be called even for stores where it's not defined in case it's
bound to be a no-op.
The “no-op detection” mechanism was only detecting the case wher `buildPaths`
was called on a set of (non-drv) paths that were already present on the store.
This commit extends this mechanism to also detect the case where `buildPaths`
is called on a set of derivation outputs which are already built on the store.
This only works with the ca-derivations flag. It could be possible to
extend this to also work without it, but it would add quite a bit of
complexity, and it's not used without it anyways.
Extend `FSAccessor::readFile` to allow not checking that the path is a
valid one, and rewrite `readInvalidDerivation` using this extended
`readFile`.
Several places in the code use `readInvalidDerivation`, either because
they need to read a derivation that has been written in the store but
not registered yet, or more generally to prevent a deadlock because
`readDerivation` tries to lock the state, so can't be called from a
place where the lock is already held.
However, `readInvalidDerivation` implicitely assumes that the store is a
`LocalFSStore`, which isn't always the case.
The concrete motivation for this is that it's required for `nix copy
--from someBinaryCache` to work, which is tremendously useful for the
tests.
In `nixStable` (2.3.7 to be precise) it's possible to connect to stores
using an IPv6 address:
nix ping-store --store ssh://root@2001:db8::1
This is also useful for `nixops(1)` where you could specify an IPv6
address in `deployment.targetHost`.
However, this behavior is broken on `nixUnstable` and fails with the
following error:
$ nix store ping --store ssh://root@2001:db8::1
don't know how to open Nix store 'ssh://root@2001:db8::1'
This happened because `openStore` from `libstore` uses the `parseURL`
function from `libfetchers` which expects a valid URL as defined in
RFC2732. However, this is unsupported by `ssh(1)`:
$ nix store ping --store 'ssh://root@[2001:db8::1]'
cannot connect to 'root@[2001:db8::1]'
This patch now allows both ways of specifying a store (`root@2001:db8::1`) and
also `root@[2001:db8::1]` since the latter one is useful to pass query
parameters to the remote store.
In order to achieve this, the following changes were made:
* The URL regex from `url-parts.hh` now allows an IPv6 address in the
form `2001:db8::1` and also `[2001:db8::1]`.
* In `libstore`, a new function named `extractConnStr` ensures that a
proper URL is passed to e.g. `ssh(1)`:
* If a URL looks like either `[2001:db8::1]` or `root@[2001:db8::1]`,
the brackets will be removed using a regex. No additional validation
is done here as only strings parsed by `parseURL` are expected.
* In any other case, the string will be left untouched.
* The rules above only apply for `LegacySSHStore` and `SSHStore` (a.k.a
`ssh://` and `ssh-ng://`).
Unresolved questions:
* I'm not really sure whether we want to allow both variants of IPv6
addresses in the URL parser. However it should be noted that both seem
to be possible according to RFC2732:
> This document incudes an update to the generic syntax for Uniform
> Resource Identifiers defined in RFC 2396 [URL]. It defines a syntax
> for IPv6 addresses and allows the use of "[" and "]" within a URI
> explicitly for this reserved purpose.
* Currently, it's not supported to specify a port number behind the
hostname, however it seems as this is not really supported by the URL
parser. Hence, this is probably out of scope here.
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.
Rework the `Store` hierarchy so that there's now one hierarchy for the
store configs and one for the implementations (where each implementation
extends the corresponding config). So a class hierarchy like
```
StoreConfig-------->Store
| |
v v
SubStoreConfig----->SubStore
| |
v v
SubSubStoreConfig-->SubSubStore
```
(with virtual inheritance to prevent DDD).
The advantage of this architecture is that we can now introspect the configuration of a store without having to instantiate the store itself
Add a new `init()` method to the `Store` class that is supposed to
handle all the effectful initialisation needed to set-up the store.
The constructor should remain side-effect free and just initialize the
c++ data structure.
The goal behind that is that we can create “dummy” instances of each
store to query static properties about it (the parameters it accepts for
example)
Directly register the store classes rather than a function to build an
instance of them.
This gives the possibility to introspect static members of the class or
choose different ways of instantiating them.
Maximilian Bosch