reconciler: Implement tests using scripttest

Reimplement the reconciler tests using scripttest. This significantly
simplifies the test-suite and allows easier verification of more complex
scenarios.

To allow for Status JSON and YAML marshalling, define custom UnmarshalJSON
and UnmarshalYAML that also fill in the 'id'. The 'id' is used with StatusSet
to efficiently allow multiple reconcilers to manipulate the status without
conflicts, e.g. if the object status id is the same it can still be updated
with the reconciliation result even if the object conflicted due to other
reconciler's update to its status.

Signed-off-by: Jussi Maki <jussi.maki@isovalent.com>

reconciler/metrics.go

@@ -24,6 +24,8 @@ const (
 )
 
 type ExpVarMetrics struct {
+	root *expvar.Map
+
 	ReconciliationCountVar         *expvar.Map
 	ReconciliationDurationVar      *expvar.Map
 	ReconciliationTotalErrorsVar   *expvar.Map
@@ -73,14 +75,22 @@ func NewUnpublishedExpVarMetrics() *ExpVarMetrics {
 	return newExpVarMetrics(false)
 }
 
+func (m *ExpVarMetrics) Map() *expvar.Map {
+	return m.root
+}
+
 func newExpVarMetrics(publish bool) *ExpVarMetrics {
+	root := new(expvar.Map).Init()
 	newMap := func(name string) *expvar.Map {
 		if publish {
 			return expvar.NewMap(name)
 		}
-		return new(expvar.Map).Init()
+		m := new(expvar.Map).Init()
+		root.Set(name, m)
+		return m
 	}
 	return &ExpVarMetrics{
+		root:                           root,
 		ReconciliationCountVar:         newMap("reconciliation_count"),
 		ReconciliationDurationVar:      newMap("reconciliation_duration"),
 		ReconciliationTotalErrorsVar:   newMap("reconciliation_total_errors"),

reconciler/multi_test.go

@@ -82,6 +82,11 @@ func TestMultipleReconcilers(t *testing.T) {
 		cell.Provide(
 			cell.NewSimpleHealth,
 			reconciler.NewExpVarMetrics,
+			func(r job.Registry, h cell.Health, lc cell.Lifecycle) job.Group {
+				g := r.NewGroup(h)
+				lc.Append(g)
+				return g
+			},
 		),
 		cell.Invoke(func(db_ *statedb.DB) error {
 			db = db_