servicelb pool selector

adds a new optional node label
"svccontroller.k3s.cattle.io/lbpool=<pool>" that can be set on nodes.
ServiceType: LoadBalancer services can then specify a matching label,
which will schedule the DaemonSet only on specified nodes. This allows
operators to specify different pools of nodes that can serve different
LoadBalancer services on the same ports.

Signed-off-by: robertlestak <robert.lestak@umusic.com>

pkg/servicelb/controller.go

@@ -32,10 +32,11 @@ import (
 )
 
 var (
-	svcNameLabel       = "svccontroller." + version.Program + ".cattle.io/svcname"
-	daemonsetNodeLabel = "svccontroller." + version.Program + ".cattle.io/enablelb"
-	nodeSelectorLabel  = "svccontroller." + version.Program + ".cattle.io/nodeselector"
-	DefaultLBImage     = "rancher/klipper-lb:v0.3.4"
+	svcNameLabel           = "svccontroller." + version.Program + ".cattle.io/svcname"
+	daemonsetNodeLabel     = "svccontroller." + version.Program + ".cattle.io/enablelb"
+	daemonsetNodePoolLabel = "svccontroller." + version.Program + ".cattle.io/lbpool"
+	nodeSelectorLabel      = "svccontroller." + version.Program + ".cattle.io/nodeselector"
+	DefaultLBImage         = "rancher/klipper-lb:v0.3.4"
 )
 
 const (
@@ -499,6 +500,10 @@ func (h *handler) newDaemonSet(svc *core.Service) (*apps.DaemonSet, error) {
 		ds.Spec.Template.Spec.NodeSelector = map[string]string{
 			daemonsetNodeLabel: "true",
 		}
+		// Add node selector for "svccontroller.k3s.cattle.io/lbpool=<pool>" if service has lbpool label
+		if svc.Labels[daemonsetNodePoolLabel] != "" {
+			ds.Spec.Template.Spec.NodeSelector[daemonsetNodePoolLabel] = svc.Labels[daemonsetNodePoolLabel]
+		}
 		ds.Labels[nodeSelectorLabel] = "true"
 	}
 	return ds, nil