Create machine utils file

Currenly contains only single method to decide if the machine
object has healthy state.

pkg/util/machines/machines.go

@@ -0,0 +1,76 @@
+package machines
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/golang/glog"
+	mapiv1 "github.com/openshift/cluster-api/pkg/apis/machine/v1beta1"
+	healthcheckingv1alpha1 "github.com/openshift/machine-api-operator/pkg/apis/healthchecking/v1alpha1"
+	"github.com/openshift/machine-api-operator/pkg/util/conditions"
+
+	"k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/labels"
+
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+// IsMachineHealthy returns true if the the machine is running and machine node is healthy
+func IsMachineHealthy(c client.Client, machine *mapiv1.Machine) bool {
+	if machine.Status.NodeRef == nil {
+		glog.Infof("machine %s does not have NodeRef", machine.Name)
+		return false
+	}
+
+	node := &v1.Node{}
+	key := client.ObjectKey{Namespace: metav1.NamespaceNone, Name: machine.Status.NodeRef.Name}
+	err := c.Get(context.TODO(), key, node)
+	if err != nil {
+		glog.Errorf("failed to fetch node for machine %s", machine.Name)
+	}
+
+	readyCond := conditions.GetNodeCondition(node, v1.NodeReady)
+	if readyCond == nil {
+		glog.Infof("node %s does have 'Ready' condition", machine.Name)
+		return false
+	}
+
+	if readyCond.Status != v1.ConditionTrue {
+		glog.Infof("node %s does have has 'Ready' condition with the status %s", machine.Name, readyCond.Status)
+		return false
+	}
+	return true
+}
+
+// GetMachineMachineDisruptionBudgets returns list of machine disruption budgets that suit for the machine
+func GetMachineMachineDisruptionBudgets(c client.Client, machine *mapiv1.Machine) ([]*healthcheckingv1alpha1.MachineDisruptionBudget, error) {
+	if len(machine.Labels) == 0 {
+		return nil, fmt.Errorf("no MachineDisruptionBudgets found for machine %v because it has no labels", machine.Name)
+	}
+
+	list := &healthcheckingv1alpha1.MachineDisruptionBudgetList{}
+	listOptions := &client.ListOptions{Namespace: machine.Namespace}
+	err := c.List(context.TODO(), listOptions, list)
+	if err != nil {
+		return nil, err
+	}
+
+	var mdbs []*healthcheckingv1alpha1.MachineDisruptionBudget
+	for i := range list.Items {
+		mdb := &list.Items[i]
+		selector, err := metav1.LabelSelectorAsSelector(mdb.Spec.Selector)
+		if err != nil {
+			glog.Warningf("invalid selector: %v", err)
+			continue
+		}
+
+		// If a mdb with a nil or empty selector creeps in, it should match nothing, not everything.
+		if selector.Empty() || !selector.Matches(labels.Set(machine.Labels)) {
+			continue
+		}
+		mdbs = append(mdbs, mdb)
+	}
+
+	return mdbs, nil
+}