zones: ignore machine-less zones

Signed-off-by: Alejandro Mery <amery@jpi.io>

pkg/zones/scan.go

@@ -3,6 +3,8 @@ package zones
 import (
 	"io/fs"
 	"sort"
+
+	"darvaza.org/core"
 )
 
 func (m *Zones) scan(opts *ScanOptions) error {
@@ -31,21 +33,30 @@ func (m *Zones) scanDirectory(_ *ScanOptions) error {
 
 	for _, e := range entries {
 		if e.IsDir() {
+			z, err := m.newZone(e.Name())
+			switch {
+			case err != nil:
+				return core.Wrap(err, e.Name())
+			case z.Machines.Len() > 0:
+				m.Zones = append(m.Zones, z)
+			}
+		}
+	}
+
+	return nil
+}
+
+func (m *Zones) newZone(name string) (*Zone, error) {
 	z := &Zone{
 		zones:  m,
 		logger: m,
-				Name:   e.Name(),
+		Name:   name,
 	}
 
 	if err := z.scan(); err != nil {
-				return err
+		return nil, err
 	}
-
+	return z, nil
-			m.Zones = append(m.Zones, z)
-		}
-	}
-
-	return nil
 }
 
 func (m *Zones) scanMachines(opts *ScanOptions) error {