Added a NodeAffinity PreFilter that looks for node.Name MatchField terms; if exist, the pod is only evaluated against the matching nodes.

pkg/scheduler/framework/plugins/nodeaffinity/node_affinity.go

@@ -20,8 +20,10 @@ import (
 	"context"
 	"fmt"
 
-	v1 "k8s.io/api/core/v1"
+	"k8s.io/api/core/v1"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/component-helpers/scheduling/corev1/nodeaffinity"
 	"k8s.io/kubernetes/pkg/scheduler/apis/config"
 	"k8s.io/kubernetes/pkg/scheduler/apis/config/validation"
@@ -58,6 +60,9 @@ const (
 
 	// errReasonEnforced is the reason for added node affinity not matching.
 	errReasonEnforced = "node(s) didn't match scheduler-enforced node affinity"
+
+	// errReasonConflict is the reason for pod's conflicting affinity rules.
+	errReasonConflict = "pod affinity terms conflict"
 )
 
 // Name returns name of the plugin. It is used in logs, etc.
@@ -86,7 +91,48 @@ func (pl *NodeAffinity) EventsToRegister() []framework.ClusterEvent {
 func (pl *NodeAffinity) PreFilter(ctx context.Context, cycleState *framework.CycleState, pod *v1.Pod) (*framework.PreFilterResult, *framework.Status) {
 	state := &preFilterState{requiredNodeSelectorAndAffinity: nodeaffinity.GetRequiredNodeAffinity(pod)}
 	cycleState.Write(preFilterStateKey, state)
+	affinity := pod.Spec.Affinity
+	if affinity == nil ||
+		affinity.NodeAffinity == nil ||
+		affinity.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution == nil ||
+		len(affinity.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms) == 0 {
 		return nil, nil
+	}
+
+	// Check if there is affinity to a specific node and return it.
+	terms := affinity.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms
+	var nodeNames sets.String
+	for _, t := range terms {
+		var termNodeNames sets.String
+		for _, r := range t.MatchFields {
+			if r.Key == metav1.ObjectNameField && r.Operator == v1.NodeSelectorOpIn {
+				// The requirements represent ANDed constraints, and so we need to
+				// find the intersection of nodes.
+				s := sets.NewString(r.Values...)
+				if termNodeNames == nil {
+					termNodeNames = s
+				} else {
+					termNodeNames = termNodeNames.Intersection(s)
+				}
+			}
+		}
+		if termNodeNames == nil {
+			// If this term has no node.Name field affinity,
+			// then all nodes are eligible because the terms are ORed.
+			return nil, nil
+		}
+		// If the set is empty, it means the terms had affinity to different
+		// sets of nodes, and since they are ANDed, then the pod will not match any node.
+		if len(termNodeNames) == 0 {
+			return nil, framework.NewStatus(framework.UnschedulableAndUnresolvable, errReasonConflict)
+		}
+		nodeNames = nodeNames.Union(termNodeNames)
+	}
+	if nodeNames != nil {
+		return &framework.PreFilterResult{NodeNames: nodeNames}, nil
+	}
+	return nil, nil
+
 }
 
 // PreFilterExtensions not necessary for this plugin as state doesn't depend on pod additions or deletions.

pkg/scheduler/framework/plugins/nodeaffinity/node_affinity_test.go

@@ -18,12 +18,12 @@ package nodeaffinity
 
 import (
 	"context"
-	"reflect"
 	"testing"
 
 	"github.com/google/go-cmp/cmp"
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/util/sets"
 	"k8s.io/kubernetes/pkg/scheduler/apis/config"
 	"k8s.io/kubernetes/pkg/scheduler/framework"
 	"k8s.io/kubernetes/pkg/scheduler/framework/runtime"
@@ -38,6 +38,8 @@ func TestNodeAffinity(t *testing.T) {
 		labels              map[string]string
 		nodeName            string
 		wantStatus          *framework.Status
+		wantPreFilterStatus *framework.Status
+		wantPreFilterResult *framework.PreFilterResult
 		args                config.NodeAffinityArgs
 		disablePreFilter    bool
 	}{
@@ -513,7 +515,7 @@ func TestNodeAffinity(t *testing.T) {
 											{
 												Key:      metav1.ObjectNameField,
 												Operator: v1.NodeSelectorOpIn,
-												Values:   []string{"node_1"},
+												Values:   []string{"node1"},
 											},
 										},
 									},
@@ -523,7 +525,8 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName: "node_1",
+			nodeName:            "node1",
+			wantPreFilterResult: &framework.PreFilterResult{NodeNames: sets.NewString("node1")},
 		},
 		{
 			name: "Pod with matchFields using In operator that does not match the existing node",
@@ -538,7 +541,7 @@ func TestNodeAffinity(t *testing.T) {
 											{
 												Key:      metav1.ObjectNameField,
 												Operator: v1.NodeSelectorOpIn,
-												Values:   []string{"node_1"},
+												Values:   []string{"node1"},
 											},
 										},
 									},
@@ -548,8 +551,9 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName:   "node_2",
+			nodeName:            "node2",
 			wantStatus:          framework.NewStatus(framework.UnschedulableAndUnresolvable, ErrReasonPod),
+			wantPreFilterResult: &framework.PreFilterResult{NodeNames: sets.NewString("node1")},
 		},
 		{
 			name: "Pod with two terms: matchFields does not match, but matchExpressions matches",
@@ -564,7 +568,7 @@ func TestNodeAffinity(t *testing.T) {
 											{
 												Key:      metav1.ObjectNameField,
 												Operator: v1.NodeSelectorOpIn,
-												Values:   []string{"node_1"},
+												Values:   []string{"node1"},
 											},
 										},
 									},
@@ -583,7 +587,7 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName: "node_2",
+			nodeName: "node2",
 			labels:   map[string]string{"foo": "bar"},
 		},
 		{
@@ -599,7 +603,7 @@ func TestNodeAffinity(t *testing.T) {
 											{
 												Key:      metav1.ObjectNameField,
 												Operator: v1.NodeSelectorOpIn,
-												Values:   []string{"node_1"},
+												Values:   []string{"node1"},
 											},
 										},
 										MatchExpressions: []v1.NodeSelectorRequirement{
@@ -616,8 +620,9 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName:   "node_2",
+			nodeName:            "node2",
 			labels:              map[string]string{"foo": "bar"},
+			wantPreFilterResult: &framework.PreFilterResult{NodeNames: sets.NewString("node1")},
 			wantStatus:          framework.NewStatus(framework.UnschedulableAndUnresolvable, ErrReasonPod),
 		},
 		{
@@ -633,7 +638,7 @@ func TestNodeAffinity(t *testing.T) {
 											{
 												Key:      metav1.ObjectNameField,
 												Operator: v1.NodeSelectorOpIn,
-												Values:   []string{"node_1"},
+												Values:   []string{"node1"},
 											},
 										},
 										MatchExpressions: []v1.NodeSelectorRequirement{
@@ -650,8 +655,9 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName: "node_1",
+			nodeName:            "node1",
 			labels:              map[string]string{"foo": "bar"},
+			wantPreFilterResult: &framework.PreFilterResult{NodeNames: sets.NewString("node1")},
 		},
 		{
 			name: "Pod with two terms: both matchFields and matchExpressions do not match",
@@ -666,7 +672,7 @@ func TestNodeAffinity(t *testing.T) {
 											{
 												Key:      metav1.ObjectNameField,
 												Operator: v1.NodeSelectorOpIn,
-												Values:   []string{"node_1"},
+												Values:   []string{"node1"},
 											},
 										},
 									},
@@ -685,10 +691,78 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName:   "node_2",
+			nodeName:   "node2",
 			labels:     map[string]string{"foo": "bar"},
 			wantStatus: framework.NewStatus(framework.UnschedulableAndUnresolvable, ErrReasonPod),
 		},
+		{
+			name: "Pod with two terms of node.Name affinity",
+			pod: &v1.Pod{
+				Spec: v1.PodSpec{
+					Affinity: &v1.Affinity{
+						NodeAffinity: &v1.NodeAffinity{
+							RequiredDuringSchedulingIgnoredDuringExecution: &v1.NodeSelector{
+								NodeSelectorTerms: []v1.NodeSelectorTerm{
+									{
+										MatchFields: []v1.NodeSelectorRequirement{
+											{
+												Key:      metav1.ObjectNameField,
+												Operator: v1.NodeSelectorOpIn,
+												Values:   []string{"node1"},
+											},
+										},
+									},
+									{
+										MatchFields: []v1.NodeSelectorRequirement{
+											{
+												Key:      metav1.ObjectNameField,
+												Operator: v1.NodeSelectorOpIn,
+												Values:   []string{"node2"},
+											},
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			nodeName:            "node2",
+			wantPreFilterResult: &framework.PreFilterResult{NodeNames: sets.NewString("node1", "node2")},
+		},
+		{
+			name: "Pod with two conflicting mach field requirements",
+			pod: &v1.Pod{
+				Spec: v1.PodSpec{
+					Affinity: &v1.Affinity{
+						NodeAffinity: &v1.NodeAffinity{
+							RequiredDuringSchedulingIgnoredDuringExecution: &v1.NodeSelector{
+								NodeSelectorTerms: []v1.NodeSelectorTerm{
+									{
+										MatchFields: []v1.NodeSelectorRequirement{
+											{
+												Key:      metav1.ObjectNameField,
+												Operator: v1.NodeSelectorOpIn,
+												Values:   []string{"node1"},
+											},
+											{
+												Key:      metav1.ObjectNameField,
+												Operator: v1.NodeSelectorOpIn,
+												Values:   []string{"node2"},
+											},
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			nodeName:            "node2",
+			labels:              map[string]string{"foo": "bar"},
+			wantPreFilterStatus: framework.NewStatus(framework.UnschedulableAndUnresolvable, errReasonConflict),
+			wantStatus:          framework.NewStatus(framework.UnschedulableAndUnresolvable, ErrReasonPod),
+		},
 		{
 			name: "Matches added affinity and Pod's node affinity",
 			pod: &v1.Pod{
@@ -712,7 +786,7 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName: "node_2",
+			nodeName: "node2",
 			labels:   map[string]string{"zone": "foo"},
 			args: config.NodeAffinityArgs{
 				AddedAffinity: &v1.NodeAffinity{
@@ -721,7 +795,7 @@ func TestNodeAffinity(t *testing.T) {
 							MatchFields: []v1.NodeSelectorRequirement{{
 								Key:      metav1.ObjectNameField,
 								Operator: v1.NodeSelectorOpIn,
-								Values:   []string{"node_2"},
+								Values:   []string{"node2"},
 							}},
 						}},
 					},
@@ -751,7 +825,7 @@ func TestNodeAffinity(t *testing.T) {
 					},
 				},
 			},
-			nodeName: "node_2",
+			nodeName: "node2",
 			labels:   map[string]string{"zone": "foo"},
 			args: config.NodeAffinityArgs{
 				AddedAffinity: &v1.NodeAffinity{
@@ -760,7 +834,7 @@ func TestNodeAffinity(t *testing.T) {
 							MatchFields: []v1.NodeSelectorRequirement{{
 								Key:      metav1.ObjectNameField,
 								Operator: v1.NodeSelectorOpIn,
-								Values:   []string{"node_2"},
+								Values:   []string{"node2"},
 							}},
 						}},
 					},
@@ -771,7 +845,7 @@ func TestNodeAffinity(t *testing.T) {
 		{
 			name:     "Doesn't match added affinity",
 			pod:      &v1.Pod{},
-			nodeName: "node_2",
+			nodeName: "node2",
 			labels:   map[string]string{"zone": "foo"},
 			args: config.NodeAffinityArgs{
 				AddedAffinity: &v1.NodeAffinity{
@@ -855,14 +929,17 @@ func TestNodeAffinity(t *testing.T) {
 			state := framework.NewCycleState()
 			var gotStatus *framework.Status
 			if !test.disablePreFilter {
-				_, gotStatus = p.(framework.PreFilterPlugin).PreFilter(context.Background(), state, test.pod)
+				gotPreFilterResult, gotStatus := p.(framework.PreFilterPlugin).PreFilter(context.Background(), state, test.pod)
-				if !gotStatus.IsSuccess() {
+				if diff := cmp.Diff(test.wantPreFilterStatus, gotStatus); diff != "" {
-					t.Errorf("unexpected error: %v", gotStatus)
+					t.Errorf("unexpected PreFilter Status (-want,+got):\n%s", diff)
+				}
+				if diff := cmp.Diff(test.wantPreFilterResult, gotPreFilterResult); diff != "" {
+					t.Errorf("unexpected PreFilterResult (-want,+got):\n%s", diff)
 				}
 			}
 			gotStatus = p.(framework.FilterPlugin).Filter(context.Background(), state, test.pod, nodeInfo)
-			if !reflect.DeepEqual(gotStatus, test.wantStatus) {
+			if diff := cmp.Diff(test.wantStatus, gotStatus); diff != "" {
-				t.Errorf("status does not match: %v, want: %v", gotStatus, test.wantStatus)
+				t.Errorf("unexpected Filter Status (-want,+got):\n%s", diff)
 			}
 		})
 	}