Minimal CA support

This verison has a worse UI, but also chnages the schema less: One
non-null constraint is removed, but no new columns are added.

Co-Authored-By: Andrea Ciceri <andrea.ciceri@autistici.org>
Co-Authored-By: regnat <rg@regnat.ovh>

t/content-addressed/basic.t

@@ -0,0 +1,61 @@
+use feature 'unicode_strings';
+use strict;
+use warnings;
+use Setup;
+
+my %ctx = test_init(
+    nix_config => qq|
+    experimental-features = ca-derivations
+    |,
+);
+
+require Hydra::Schema;
+require Hydra::Model::DB;
+
+use JSON::MaybeXS;
+
+use HTTP::Request::Common;
+use Test2::V0;
+require Catalyst::Test;
+Catalyst::Test->import('Hydra');
+
+my $db = Hydra::Model::DB->new;
+hydra_setup($db);
+
+my $project = $db->resultset('Projects')->create({name => "tests", displayname => "", owner => "root"});
+
+my $jobset = createBaseJobset("content-addressed", "content-addressed.nix", $ctx{jobsdir});
+
+ok(evalSucceeds($jobset), "Evaluating jobs/content-addressed.nix should exit with return code 0");
+is(nrQueuedBuildsForJobset($jobset), 5, "Evaluating jobs/content-addressed.nix should result in 4 builds");
+
+for my $build (queuedBuildsForJobset($jobset)) {
+    ok(runBuild($build), "Build '".$build->job."' from jobs/content-addressed.nix should exit with code 0");
+    my $newbuild = $db->resultset('Builds')->find($build->id);
+    is($newbuild->finished, 1, "Build '".$build->job."' from jobs/content-addressed.nix should be finished.");
+    my $expected = $build->job eq "fails" ? 1 : $build->job =~ /with_failed/ ? 6 : 0;
+    is($newbuild->buildstatus, $expected, "Build '".$build->job."' from jobs/content-addressed.nix should have buildstatus $expected.");
+
+    my $response = request("/build/".$build->id);
+    ok($response->is_success, "The 'build' page for build '".$build->job."' should load properly");
+
+    if ($newbuild->buildstatus == 0) {
+      my $buildOutputs = $newbuild->buildoutputs;
+      for my $output ($newbuild->buildoutputs) {
+        # XXX: This hardcodes /nix/store/.
+        # It's fine because in practice the nix store for the tests will be of
+        # the form `/some/thing/nix/store/`, but it would be cleaner if there
+        # was a way to query Nix for its store dir?
+        like(
+          $output->path, qr|/nix/store/|,
+          "Output '".$output->name."' of build '".$build->job."' should be a valid store path"
+        );
+      }
+    }
+
+}
+
+isnt(<$ctx{deststoredir}/realisations/*>, "", "The destination store should have the realisations of the built derivations registered");
+
+done_testing;
+

t/content-addressed/without-experimental-feature.t

@@ -0,0 +1,28 @@
+use feature 'unicode_strings';
+use strict;
+use warnings;
+use Setup;
+
+my %ctx = test_init();
+
+require Hydra::Schema;
+require Hydra::Model::DB;
+
+use JSON::MaybeXS;
+
+use HTTP::Request::Common;
+use Test2::V0;
+require Catalyst::Test;
+Catalyst::Test->import('Hydra');
+
+my $db = Hydra::Model::DB->new;
+hydra_setup($db);
+
+my $project = $db->resultset('Projects')->create({name => "tests", displayname => "", owner => "root"});
+
+my $jobset = createBaseJobset("content-addressed", "content-addressed.nix", $ctx{jobsdir});
+
+ok(evalSucceeds($jobset),                  "Evaluating jobs/content-addressed.nix without the experimental feature should exit with return code 0");
+is(nrQueuedBuildsForJobset($jobset), 0, "Evaluating jobs/content-addressed.nix without the experimental Nix feature should result in 0 build");
+
+done_testing;

t/jobs/config.nix.in

@@ -6,4 +6,9 @@ rec {
       system = builtins.currentSystem;
       PATH = path;
     } // args);
+  mkContentAddressedDerivation = args: mkDerivation ({
+    __contentAddressed = true;
+    outputHashMode = "recursive";
+    outputHashAlgo = "sha256";
+  } // args);
 }

t/jobs/content-addressed.nix

@@ -0,0 +1,35 @@
+let cfg =  import ./config.nix; in
+rec {
+  empty_dir =
+    cfg.mkContentAddressedDerivation {
+      name = "empty-dir";
+      builder = ./empty-dir-builder.sh;
+    };
+
+  fails =
+    cfg.mkContentAddressedDerivation {
+      name = "fails";
+      builder = ./fail.sh;
+    };
+
+  succeed_with_failed =
+    cfg.mkContentAddressedDerivation {
+      name = "succeed-with-failed";
+      builder = ./succeed-with-failed.sh;
+    };
+
+  caDependingOnCA =
+    cfg.mkContentAddressedDerivation {
+      name = "ca-depending-on-ca";
+      builder = ./dir-with-file-builder.sh;
+      FOO = empty_dir;
+    };
+
+  nonCaDependingOnCA =
+    cfg.mkDerivation {
+      name = "non-ca-depending-on-ca";
+      builder = ./dir-with-file-builder.sh;
+      FOO = empty_dir;
+    };
+}
+

t/jobs/dir-with-file-builder.sh

@@ -0,0 +1,7 @@
+#! /bin/sh
+
+# Workaround for https://github.com/NixOS/nix/pull/6051
+echo "some output"
+
+mkdir $out
+echo foo > $out/a-file

t/queue-runner/notifications.t

@@ -8,7 +8,7 @@ my $binarycachedir = File::Temp->newdir();
 
 my $ctx = test_context(
     nix_config => qq|
-    experimental-features = nix-command
+    experimental-features = nix-command ca-derivations
     substituters = file://${binarycachedir}?trusted=1
     |,
     hydra_config => q|