Commit graph

14 commits

Author SHA1 Message Date
Naïm Favier
15f7fa59be
unsafeDiscardReferences
Adds a new boolean structured attribute
`outputChecks.<output>.unsafeDiscardReferences` which disables scanning
an output for runtime references.

    __structuredAttrs = true;
    outputChecks.out.unsafeDiscardReferences = true;

This is useful when creating filesystem images containing their own embedded Nix
store: they are self-contained blobs of data with no runtime dependencies.

Setting this attribute requires the experimental feature
`discard-references` to be enabled.
2023-01-03 17:19:16 +01:00
Eelco Dolstra
128910ba23 Separate cgroup support from auto-uid-allocation
The new experimental feature 'cgroups' enables the use of cgroups for
all builds. This allows better containment and enables setting
resource limits and getting some build stats.
2022-11-18 10:39:28 +01:00
Eelco Dolstra
6c6eff8ac4 Remove the SystemdCgroup feature 2022-11-10 17:24:12 +01:00
Eelco Dolstra
40911d7dec Remove stray tab 2022-11-04 13:30:35 +01:00
Eelco Dolstra
b95faccf03 Merge remote-tracking branch 'origin/master' into auto-uid-allocation 2022-11-03 17:43:40 +01:00
Tom Bereknyei
7a04fb1c56 repl: add repl-flake experimental feature for gating 2022-05-20 08:20:00 -04:00
Alain Zscheile
1385b20078
Get rid of most .at calls (#6393)
Use one of `get` or `getOr` instead which will either return a null-pointer (with a nicer error message) or a default value when the key is missing.
2022-05-04 07:44:32 +02:00
Eelco Dolstra
a3c6c5b1c7 nix profile: Support overriding outputs 2022-05-03 15:00:34 +02:00
Yorick van Pelt
ebf2fd76b1
Add custom to_json and from_json functions for ExperimentalFeature
nix show-config --json was serializing experimental features as ints.
nlohmann::json will automatically use these definitions to serialize
and deserialize ExperimentalFeatures.

Strictly, we don't use the from_json instance yet, it's provided for
completeness and hopefully future use.
2022-04-20 15:41:01 +02:00
Eelco Dolstra
5cd72598fe Add support for impure derivations
Impure derivations are derivations that can produce a different result
every time they're built. Example:

  stdenv.mkDerivation {
    name = "impure";
    __impure = true; # marks this derivation as impure
    outputHashAlgo = "sha256";
    outputHashMode = "recursive";
    buildCommand = "date > $out";
  };

Some important characteristics:

* This requires the 'impure-derivations' experimental feature.

* Impure derivations are not "cached". Thus, running "nix-build" on
  the example above multiple times will cause a rebuild every time.

* They are implemented similar to CA derivations, i.e. the output is
  moved to a content-addressed path in the store. The difference is
  that we don't register a realisation in the Nix database.

* Pure derivations are not allowed to depend on impure derivations. In
  the future fixed-output derivations will be allowed to depend on
  impure derivations, thus forming an "impurity barrier" in the
  dependency graph.

* When sandboxing is enabled, impure derivations can access the
  network in the same way as fixed-output derivations. In relaxed
  sandboxing mode, they can access the local filesystem.
2022-03-31 13:43:20 +02:00
Eelco Dolstra
f902f3c2cb Add experimental feature 'fetch-closure' 2022-03-24 21:33:33 +01:00
John Ericson
dc92b01885 Merge remote-tracking branch 'upstream/master' into auto-uid-allocation 2022-02-28 23:54:20 +00:00
Eelco Dolstra
0d9e050ba7 parseExperimentalFeature(): Initialize atomically 2021-10-26 14:29:48 +02:00
regnat
af99941279 Make experimental-features a proper type
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.
2021-10-26 07:02:31 +02:00