zones: SyncWireguardConfig() as Prune+Write

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

pkg/zones/wireguard.go

@@ -14,6 +14,9 @@ var (
 	_ WireguardConfigWriter = (*Zone)(nil)
 	_ WireguardConfigWriter = (*Machine)(nil)
 
+	_ WireguardConfigSyncer = (*Zones)(nil)
+	_ WireguardConfigSyncer = (*Zone)(nil)
+
 	_ WireguardKeysWriter = (*Zones)(nil)
 	_ WireguardKeysWriter = (*Zone)(nil)
 	_ WireguardKeysWriter = (*Machine)(nil)
@@ -142,6 +145,61 @@ func (m *Machine) writeWireguardRingConfig(r *Ring) error {
 	return err
 }
 
+// A WireguardConfigSyncer updates all wgN.conf on all machines under
+// its scope reflecting the state of the ring
+type WireguardConfigSyncer interface {
+	SyncWireguardConfig(ring int) error
+}
+
+// SyncWireguardConfig updates all wgN.conf files for the specified
+// ring
+func (m *Zones) SyncWireguardConfig(ring int) error {
+	switch ring {
+	case 0:
+		return syncWireguardConfig(m, m, ring)
+	case 1:
+		var err error
+		m.ForEachZone(func(z *Zone) bool {
+			err = syncWireguardConfig(m, z, ring)
+			return err != nil
+		})
+		return err
+	default:
+		return fs.ErrInvalid
+	}
+}
+
+// SyncWireguardConfig updates all wgN.conf files for the specified
+// ring
+func (z *Zone) SyncWireguardConfig(ring int) error {
+	switch ring {
+	case 0:
+		return syncWireguardConfig(z.zones, z.zones, ring)
+	case 1:
+		return syncWireguardConfig(z.zones, z, ring)
+	default:
+		return fs.ErrInvalid
+	}
+}
+
+func syncWireguardConfig(z ZoneIterator, m MachineIterator, ring int) error {
+	r, err := NewRing(z, m, ring)
+	if err != nil {
+		return err
+	}
+
+	r.ForEachMachine(func(p *Machine) bool {
+		if _, ok := p.getRingInfo(ring); ok {
+			err = p.writeWireguardRingConfig(r)
+		} else {
+			err = p.RemoveWireguardConfig(ring)
+		}
+		return err != nil
+	})
+
+	return err
+}
+
 // A WireguardKeysWriter writes the Wireguard Keys for all machines
 // under its scope for the specified ring
 type WireguardKeysWriter interface {