When manually scheduling an eval, force re-instantiation of store derivations

Without this, if (failed or aborted) derivations have been
garbage-collected, there is no way to restart them, which is very
annoying. Now we set a forceEval flag in the jobset to cause it to be
re-evaluated even if none of the inputs have changed.

src/lib/Hydra/Controller/API.pm

@@ -202,10 +202,11 @@ sub scmdiff : Chained('api') PathPart('scmdiff') Args(0) {
 
 
 sub triggerJobset {
-    my ($self, $c, $jobset) = @_;
+    my ($self, $c, $jobset, $force) = @_;
     print STDERR "triggering jobset ", $jobset->project->name . ":" . $jobset->name, "\n";
     txn_do($c->model('DB')->schema, sub {
         $jobset->update({ triggertime => time });
+        $jobset->update({ forceeval => 1 }) if $force;
     });
     push @{$c->{stash}->{json}->{jobsetsTriggered}}, $jobset->project->name . ":" . $jobset->name;
 }
@@ -222,12 +223,12 @@ sub push : Chained('api') PathPart('push') Args(0) {
         my ($p, $j) = parseJobsetName($s);
         my $jobset = $c->model('DB::Jobsets')->find($p, $j);
         next unless defined $jobset && ($force || ($jobset->project->enabled && $jobset->enabled));
-        triggerJobset($self, $c, $jobset);
+        triggerJobset($self, $c, $jobset, $force);
     }
 
     my @repos = split /,/, ($c->request->query_params->{repos} // "");
     foreach my $r (@repos) {
-        triggerJobset($self, $c, $_) foreach $c->model('DB::Jobsets')->search(
+        triggerJobset($self, $c, $_, $force) foreach $c->model('DB::Jobsets')->search(
             { 'project.enabled' => 1, 'me.enabled' => 1 },
             { join => 'project'
             , where => \ [ 'exists (select 1 from JobsetInputAlts where project = me.project and jobset = me.name and value = ?)', [ 'value', $r ] ]
@@ -251,7 +252,7 @@ sub push_github : Chained('api') PathPart('push-github') Args(0) {
     my $repo = $in->{repository}->{name} or die;
     print STDERR "got push from GitHub repository $owner/$repo\n";
 
-    triggerJobset($self, $c, $_) foreach $c->model('DB::Jobsets')->search(
+    triggerJobset($self, $c, $_, 0) foreach $c->model('DB::Jobsets')->search(
         { 'project.enabled' => 1, 'me.enabled' => 1 },
         { join => 'project'
         , where => \ [ 'exists (select 1 from JobsetInputAlts where project = me.project and jobset = me.name and value like ?)', [ 'value', "%github.com%$owner/$repo%" ] ]

src/lib/Hydra/Schema/Jobsets.pm

@@ -129,6 +129,11 @@ __PACKAGE__->table("Jobsets");
   data_type: 'text'
   is_nullable: 1
 
+=head2 forceeval
+
+  data_type: 'boolean'
+  is_nullable: 1
+
 =cut
 
 __PACKAGE__->add_columns(
@@ -166,6 +171,8 @@ __PACKAGE__->add_columns(
   { data_type => "integer", default_value => 100, is_nullable => 0 },
   "fetcherrormsg",
   { data_type => "text", is_nullable => 1 },
+  "forceeval",
+  { data_type => "boolean", is_nullable => 1 },
 );
 
 =head1 PRIMARY KEY
@@ -338,8 +345,8 @@ __PACKAGE__->has_many(
 );
 
 
-# Created by DBIx::Class::Schema::Loader v0.07043 @ 2015-07-30 16:52:20
-# DO NOT MODIFY THIS OR ANYTHING ABOVE! md5sum:Coci9FdBAvUO9T3st2NEqA
+# Created by DBIx::Class::Schema::Loader v0.07045 @ 2016-10-24 20:12:51
+# DO NOT MODIFY THIS OR ANYTHING ABOVE! md5sum:PSR66NnVRNTMFhDEm10erA
 
 my %hint = (
     columns => [

src/script/hydra-eval-jobset

@@ -149,7 +149,7 @@ sub checkJobsetWrapped {
     my @args = ($jobset->nixexprinput, $jobset->nixexprpath, inputsToArgs($inputInfo, $exprType));
     my $argsHash = sha256_hex("@args");
     my $prevEval = getPrevJobsetEval($db, $jobset, 0);
-    if (defined $prevEval && $prevEval->hash eq $argsHash && !$dryRun) {
+    if (defined $prevEval && $prevEval->hash eq $argsHash && !$dryRun && !$jobset->forceeval) {
         print STDERR "  jobset is unchanged, skipping\n";
         Net::Statsd::increment("hydra.evaluator.unchanged_checkouts");
         txn_do($db, sub {
@@ -279,7 +279,7 @@ sub checkJobsetWrapped {
         # If this is a one-shot jobset, disable it now.
         $jobset->update({ enabled => 0 }) if $jobset->enabled == 2;
 
-        $jobset->update({ lastcheckedtime => time });
+        $jobset->update({ lastcheckedtime => time, forceeval => undef });
     });
 
     my $dbStop = clock_gettime(CLOCK_REALTIME);

src/sql/hydra.sql

@@ -68,6 +68,7 @@ create table Jobsets (
     checkInterval integer not null default 300, -- minimum time in seconds between polls (0 = disable polling)
     schedulingShares integer not null default 100,
     fetchErrorMsg text,
+    forceEval     boolean,
     check (schedulingShares > 0),
     primary key   (project, name),
     foreign key   (project) references Projects(name) on delete cascade on update cascade

src/sql/upgrade-51.sql

@@ -0,0 +1 @@
+alter table Jobsets add column forceEval boolean;