Convert fortress errors in the uniter

In order to prevent the uniter from putting the unit into error when it's dependents shut down in preparation for a model migration, an error translation function is now injected.
MalloZup · Dec 15, 2016 · a9445ca · a9445ca
1 parent 9f5f26d
commit a9445ca
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diff --git a/cmd/jujud/agent/unit/manifolds.go b/cmd/jujud/agent/unit/manifolds.go
@@ -226,6 +226,7 @@ func Manifolds(config ManifoldsConfig) dependency.Manifolds {
 			LeadershipTrackerName: leadershipTrackerName,
 			CharmDirName:          charmDirName,
 			HookRetryStrategyName: hookRetryStrategyName,
+			TranslateResolverErr:  uniter.TranslateFortressErrors,
 		})),
 
 		// TODO (mattyw) should be added to machine agent.

diff --git a/worker/uniter/manifold.go b/worker/uniter/manifold.go
@@ -17,6 +17,7 @@ import (
 	"github.com/juju/juju/worker/dependency"
 	"github.com/juju/juju/worker/fortress"
 	"github.com/juju/juju/worker/uniter/operation"
+	"github.com/juju/juju/worker/uniter/resolver"
 )
 
 // ManifoldConfig defines the names of the manifolds on which a
@@ -109,3 +110,14 @@ func Manifold(config ManifoldConfig) dependency.Manifold {
 		},
 	}
 }
+
+// TranslateFortressErrors turns errors returned by dependent
+// manifolds due to fortress lockdown (i.e. model migration) into an
+// error which causes the resolver loop to be restarted. When this
+// happens the uniter is about to be shut down anyway.
+func TranslateFortressErrors(err error) error {
+	if fortress.IsFortressError(err) {
+		return resolver.ErrRestart
+	}
+	return err
+}