Commit graph

124 commits

Author SHA1 Message Date
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
Théophane Hufschmitt
390269ed87 Simplify the handling of the hash modulo
Rather than having four different but very similar types of hashes, make
only one, with a tag indicating whether it corresponds to a regular of
deferred derivation.

This implies a slight logical change: The original Nix+multiple-outputs
model assumed only one hash-modulo per derivation. Adding
multiple-outputs CA derivations changed this as these have one
hash-modulo per output. This change is now treating each derivation as
having one hash modulo per output.
This obviously means that we internally loose the guaranty that
all the outputs of input-addressed derivations have the same hash
modulo. But it turns out that it doesn’t matter because there’s nothing
in the code taking advantage of that fact (and it probably shouldn’t
anyways).

The upside is that it is now much easier to work with these hashes, and
we can get rid of a lot of useless `std::visit{ overloaded`.

Co-authored-by: John Ericson <John.Ericson@Obsidian.Systems>
2022-03-29 18:17:35 +02:00
John Ericson
a544ed7684 Generalize DerivationType in preparation for impure derivations 2022-03-18 14:59:56 +00:00
John Ericson
197feed51d Clean up DerivationOutput, and headers
1. `DerivationOutput` now as the `std::variant` as a base class. And the
   variants are given hierarchical names under `DerivationOutput`.

   In 8e0d0689be @matthewbauer and I
   didn't know a better idiom, and so we made it a field. But this sort
   of "newtype" is anoying for literals downstream.

   Since then we leaned the base class, inherit the constructors trick,
   e.g. used in `DerivedPath`. Switching to use that makes this more
   ergonomic, and consistent.

2. `store-api.hh` and `derivations.hh` are now independent.

   In bcde5456cc I swapped the dependency,
   but I now know it is better to just keep on using incomplete types as
   much as possible for faster compilation and good separation of
   concerns.
2022-03-17 22:35:53 +00:00
John Ericson
0948b8e94d Reduce variants for derivation hash modulo
This changes was taken from dynamic derivation (#4628). It` somewhat
undoes the refactors I first did for floating CA derivations, as the
benefit of hindsight + requirements of dynamic derivations made me
reconsider some things.

They aren't to consequential, but I figured they might be good to land
first, before the more profound changes @thufschmitt has in the works.
2022-03-11 21:20:37 +00:00
Eelco Dolstra
df552ff53e Remove std::string alias (for real this time)
Also use std::string_view in a few more places.
2022-02-25 16:13:02 +01:00
pennae
41d70a2fc8 return string_views from forceString*
once a string has been forced we already have dynamic storage allocated for it,
so we can easily reuse that storage instead of copying.
2022-01-27 17:15:43 +01:00
Eelco Dolstra
ff09acd1f9 Remove tabs 2021-09-10 11:00:50 +02:00
Robert Hensing
a61112aadf Remove unimplemented hashAlgoOpt
It was in the header but never implemented.
2021-03-17 11:27:11 +01:00
regnat
f54976d77b Simplify the case where the drv is a purely input-addressed one 2021-02-26 16:35:05 +01:00
regnat
f483b623e9 Remove the drv resolution caching mechanism
It isn't needed anymore now that don't need to eagerly resolve
everything like we used to do. So we can safely get rid of it
2021-02-19 15:48:31 +01:00
regnat
4d45839499 Fix the detection of already built drv outputs
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.
2020-12-17 11:35:24 +01:00
regnat
bab1cda0e6 Use the hash modulo in the derivation outputs
Rather than storing the derivation outputs as `drvPath!outputName` internally,
store them as `drvHashModulo!outputName` (or `outputHash!outputName` for
fixed-output derivations).

This makes the storage slightly more opaque, but enables an earlier
cutoff in cases where a fixed-output dependency changes (but keeps the
same output hash) − same as what we already do for input-addressed
derivations.
2020-12-11 21:17:23 +01:00
John Ericson
2113ae2d85 Make drv hash modulo memo table thread-safe
Let's get one step closer to the daemon not needing to fork.
2020-11-19 16:50:06 +00:00
regnat
c092fa4702 Allow non-CA derivations to depend on CA derivations 2020-10-27 07:29:23 +01:00
Eelco Dolstra
636ec17139
Remove stray DerivationOutputsAndPaths type 2020-10-09 15:41:24 +02:00
John Ericson
00135e13f4 Clarify comment a bit 2020-09-28 18:19:10 +00:00
John Ericson
2741fffa35 Ensure resolved CA derivations are written
so we can link outputs to deriver and thus properly cache.
2020-09-16 17:57:32 +00:00
John Ericson
c5ccebae00 Merge remote-tracking branch 'upstream/master' into ca-floating-upstream 2020-09-16 17:50:40 +00:00
John Ericson
3a5cdd737c Rename Derivation::pathOpt to Derivation::path
We no longer need the `*Opt` to disambiguate.
2020-09-15 15:21:39 +00:00
John Ericson
98dfd7531d Fix querying outputs for CA derivations some more
If we resolve using the known path of a derivation whose output we
didn't have, we previously blew up. Now we just fail gracefully,
returning the map of all outputs unknown.
2020-09-04 18:33:58 +00:00
John Ericson
075d399e3f Merge remote-tracking branch 'obsidian/single-ca-drv-build' into ca-floating-upstream 2020-09-04 16:04:35 +00:00
John Ericson
e9fad3006b Fix some of the issues raised by @edolstra
- More and better comments

 - The easier renames
2020-09-04 15:18:25 +00:00
John Ericson
aad4abcc9c Fix floating CA tests
We will sometimes try to query the outputs of derivations we can't
resolve. That's fine; it just means we don't know what those outputs are
yet.
2020-09-04 01:17:38 +00:00
John Ericson
48e8828050 Merge remote-tracking branch 'obsidian/single-ca-drv-build' into ca-floating-upstream 2020-08-28 20:38:25 +00:00
John Ericson
8017fe7487 Merge remote-tracking branch 'upstream/master' into single-ca-drv-build 2020-08-28 19:59:14 +00:00
Eelco Dolstra
eb75282b8d
Merge pull request #3434 from Ericson2314/derivation-header-include-order
Revise division of labor in deserialization of derivations
2020-08-27 16:39:28 +02:00
John Ericson
8eb73a8724 CA derivations that depend on other CA derivations
Co-authored-by: Théophane Hufschmitt <regnat@users.noreply.github.com>
2020-08-24 19:01:15 +00:00
John Ericson
e0b0e18905 Add constructor for BasicDerivation -> Derivation 2020-08-24 19:01:07 +00:00
John Ericson
b0b59fd05a Merge remote-tracking branch 'obsidian/write-derivation-borrow' into HEAD 2020-08-23 15:11:10 +00:00
John Ericson
35e6288be1 writeDerivation just needs a plain store reference 2020-08-23 15:01:11 +00:00
John Ericson
3a7b330b64 "Downstream placeholders" should not be store paths
Insead they should be opaque `/<hash>` like the placeholders we already
have.
2020-08-21 19:35:35 +00:00
John Ericson
950ddfdb82 Merge remote-tracking branch 'upstream/master' into derivation-header-include-order 2020-08-18 14:36:44 +00:00
John Ericson
3c8b5b6219 Merge remote-tracking branch 'upstream/master' into single-ca-drv-build 2020-08-14 17:00:13 +00:00
Eelco Dolstra
13e49be660
Merge pull request #3875 from obsidiansystems/new-interface-for-path-pathOpt
Offer a safer interface for path and pathOpt
2020-08-14 17:19:19 +02:00
John Ericson
1b5c24662b Merge branch 'small-drv-serialize-cleanup' of github.com:obsidiansystems/nix into single-ca-drv-build 2020-08-10 01:57:54 +00:00
John Ericson
bcd0629c2e Remove name parameter from writeDerivation
The name is now stored with the derivation itself.
2020-08-10 01:35:59 +00:00
John Ericson
e913a2989f Squashed get CA derivations building 2020-08-07 19:51:55 +00:00
Carlo Nucera
1d2e80ddd6 Merge branch 'master' of github.com:NixOS/nix into new-interface-for-path-pathOpt 2020-08-05 15:45:33 -04:00
John Ericson
e561a13a58 Reanme DerivationType::Regular defintion too
This is the one non-prefixed occurence
2020-08-05 14:45:56 +00:00
John Ericson
e7b0847f2d Make names more consistent 2020-08-05 14:44:39 +00:00
John Ericson
9357512d73 Merge remote-tracking branch 'upstream/master' into derivation-header-include-order 2020-08-01 19:38:35 +00:00
Carlo Nucera
d564ac1c50 Offer a safer interface for pathOpt
The new interface we offer provides a way of getting all the
DerivationOutputs with the storePaths directly, based on the observation
that it's the most common usecase.
2020-07-28 13:55:15 -04:00
John Ericson
d5bb67cfa4 Merge remote-tracking branch 'upstream/master' into optional-derivation-output-storepath 2020-07-27 14:29:32 +00:00
John Ericson
a2af25c55a Merge remote-tracking branch 'upstream/master' into misc-ca 2020-07-23 19:14:17 +00:00
John Ericson
2274f63453 Get rid of basicDerivation::findOutput
It's a tiny function which is:

 - hardly worth abstrating over, and also only used once.

 - doesn't work once we get CA drvs

I rewrote the one callsite to be forwards compatable with CA
derivations, and also potentially more performant: instead of reading in
the derivation it can ust consult the SQLite DB in the common case.
2020-07-23 14:39:02 +00:00
Carlo Nucera
007bf6d17a Merge branch 'ca-derivation-data-types' of github.com:obsidiansystems/nix into misc-ca 2020-07-20 14:14:39 -04:00
Carlo Nucera
362ae93851 Add UnimplementedError to ease grepping for these 2020-07-20 14:13:37 -04:00
John Ericson
6756cecfcf Add DerivationType::CAFloating 2020-07-17 19:55:41 +00:00
Carlo Nucera
487c5751c6 Merge branch 'ca-drv' of github.com:Ericson2314/nix into misc-ca 2020-07-17 11:32:59 -04:00