Scheduler check functions

go.mod

@@ -26,11 +26,13 @@ require (
 	github.com/prometheus/client_golang v1.18.0
 	go.uber.org/zap v1.26.0
 	golang.org/x/mod v0.17.0
+	k8s.io/kubernetes v1.29.2
 	k8s.io/utils v0.0.0-20230726121419-3b25d923346b
 )
 
 require (
 	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/blang/semver/v4 v4.0.0 // indirect
 	github.com/cespare/xxhash/v2 v2.2.0 // indirect
 	github.com/emicklei/go-restful/v3 v3.11.0 // indirect
 	github.com/evanphx/json-patch v5.6.0+incompatible // indirect
@@ -74,9 +76,12 @@ require (
 	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect
 	k8s.io/apiextensions-apiserver v0.29.2 // indirect
+	k8s.io/apiserver v0.29.2 // indirect
 	k8s.io/component-base v0.29.2 // indirect
+	k8s.io/component-helpers v0.29.2 // indirect
 	k8s.io/klog/v2 v2.110.1 // indirect
 	k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00 // indirect
+	k8s.io/kube-scheduler v0.29.2 // indirect
 	sigs.k8s.io/json v0.0.0-20221116044647-bc3834ca7abd // indirect
 	sigs.k8s.io/structured-merge-diff/v4 v4.4.1 // indirect
 	sigs.k8s.io/yaml v1.4.0 // indirect

go.sum

@@ -2,6 +2,8 @@ github.com/Jeffail/gabs/v2 v2.7.0 h1:Y2edYaTcE8ZpRsR2AtmPu5xQdFDIthFG0jYhu5PY8kg
 github.com/Jeffail/gabs/v2 v2.7.0/go.mod h1:dp5ocw1FvBBQYssgHsG7I1WYsiLRtkUaB1FEtSwvNUw=
 github.com/beorn7/perks v1.0.1 h1:VlbKKnNfV8bJzeqoa4cOKqO6bYr3WgKZxO8Z16+hsOM=
 github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/blang/semver/v4 v4.0.0 h1:1PFHFE6yCCTv8C1TeyNNarDzntLi7wMI5i/pzqYIsAM=
+github.com/blang/semver/v4 v4.0.0/go.mod h1:IbckMUScFkM3pff0VJDNKRiT6TG/YpiHIM2yvyW5YoQ=
 github.com/cespare/xxhash/v2 v2.2.0 h1:DC2CZ1Ep5Y4k3ZQ899DldepgrayRUGE6BBZ/cd9Cj44=
 github.com/cespare/xxhash/v2 v2.2.0/go.mod h1:VGX0DQ3Q6kWi7AoAeZDth3/j3BFtOZR5XLFGgcrjCOs=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
@@ -52,6 +54,8 @@ github.com/google/uuid v1.3.0 h1:t6JiXgmwXMjEs8VusXIJk2BXHsn+wx8BZdTaoZ5fu7I=
 github.com/google/uuid v1.3.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/imdario/mergo v0.3.15 h1:M8XP7IuFNsqUx6VPK2P9OSmsYsI/YFaGil0uD21V3dM=
 github.com/imdario/mergo v0.3.15/go.mod h1:WBLT9ZmE3lPoWsEzCh9LPo3TiwVN+ZKEjmz+hD27ysY=
+github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
+github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
 github.com/josharian/intern v1.0.0 h1:vlS4z54oSdjm0bgjRigI+G1HpF+tI+9rE5LLzOg8HmY=
 github.com/josharian/intern v1.0.0/go.mod h1:5DoeVV0s6jJacbCEi61lwdGj/aVlrQvzHFFd8Hwg//Y=
 github.com/json-iterator/go v1.1.12 h1:PV8peI4a0ysnczrg+LtxykD8LfKY9ML6u2jnxaEnrnM=
@@ -96,6 +100,8 @@ github.com/prometheus/procfs v0.12.0 h1:jluTpSng7V9hY0O2R9DzzJHYb2xULk9VTR1V1R/k
 github.com/prometheus/procfs v0.12.0/go.mod h1:pcuDEFsWDnvcgNzo4EEweacyhjeA9Zk3cnaOZAZEfOo=
 github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
 github.com/rogpeppe/go-internal v1.10.0/go.mod h1:UQnix2H7Ngw/k4C5ijL5+65zddjncjaFoBhdsK/akog=
+github.com/spf13/cobra v1.7.0 h1:hyqWnYt1ZQShIddO5kBpj3vu05/++x6tJ6dg8EC572I=
+github.com/spf13/cobra v1.7.0/go.mod h1:uLxZILRyS/50WlhOIKD7W6V5bgeIt+4sICxh6uRMrb0=
 github.com/spf13/pflag v1.0.5 h1:iy+VFUOCP1a+8yFto/drg2CJ5u0yRoB7fZw3DKv/JXA=
 github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An2Bg=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
@@ -186,14 +192,22 @@ k8s.io/apiextensions-apiserver v0.29.2 h1:UK3xB5lOWSnhaCk0RFZ0LUacPZz9RY4wi/yt2I
 k8s.io/apiextensions-apiserver v0.29.2/go.mod h1:aLfYjpA5p3OwtqNXQFkhJ56TB+spV8Gc4wfMhUA3/b8=
 k8s.io/apimachinery v0.29.2 h1:EWGpfJ856oj11C52NRCHuU7rFDwxev48z+6DSlGNsV8=
 k8s.io/apimachinery v0.29.2/go.mod h1:6HVkd1FwxIagpYrHSwJlQqZI3G9LfYWRPAkUvLnXTKU=
+k8s.io/apiserver v0.29.2 h1:+Z9S0dSNr+CjnVXQePG8TcBWHr3Q7BmAr7NraHvsMiQ=
+k8s.io/apiserver v0.29.2/go.mod h1:B0LieKVoyU7ykQvPFm7XSdIHaCHSzCzQWPFa5bqbeMQ=
 k8s.io/client-go v0.29.2 h1:FEg85el1TeZp+/vYJM7hkDlSTFZ+c5nnK44DJ4FyoRg=
 k8s.io/client-go v0.29.2/go.mod h1:knlvFZE58VpqbQpJNbCbctTVXcd35mMyAAwBdpt4jrA=
 k8s.io/component-base v0.29.2 h1:lpiLyuvPA9yV1aQwGLENYyK7n/8t6l3nn3zAtFTJYe8=
 k8s.io/component-base v0.29.2/go.mod h1:BfB3SLrefbZXiBfbM+2H1dlat21Uewg/5qtKOl8degM=
+k8s.io/component-helpers v0.29.2 h1:1kTIanIdqUVG2nW3e2ENVEaYbZKphqPgEdCmJvk71aw=
+k8s.io/component-helpers v0.29.2/go.mod h1:gFc/p60rYtpD8UCcNfPCmbokHT2uy0yDpmr/KKUMNAw=
 k8s.io/klog/v2 v2.110.1 h1:U/Af64HJf7FcwMcXyKm2RPM22WZzyR7OSpYj5tg3cL0=
 k8s.io/klog/v2 v2.110.1/go.mod h1:YGtd1984u+GgbuZ7e08/yBuAfKLSO0+uR1Fhi6ExXjo=
 k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00 h1:aVUu9fTY98ivBPKR9Y5w/AuzbMm96cd3YHRTU83I780=
 k8s.io/kube-openapi v0.0.0-20231010175941-2dd684a91f00/go.mod h1:AsvuZPBlUDVuCdzJ87iajxtXuR9oktsTctW/R9wwouA=
+k8s.io/kube-scheduler v0.29.2 h1:wcYkF18AUl4DPrQYpfeZQHCqQokTq7VSKaSb3d3lzOg=
+k8s.io/kube-scheduler v0.29.2/go.mod h1:yb8xrwzrdUMFU1ot3BlhKszoCfwNJlEd7tLskXe2i/I=
+k8s.io/kubernetes v1.29.2 h1:8hh1cntqdulanjQt7wSSSsJfBgOyx6fUdFWslvGL5m0=
+k8s.io/kubernetes v1.29.2/go.mod h1:xZPKU0yO0CBbLTnbd+XGyRmmtmaVuJykDb8gNCkeeUE=
 k8s.io/utils v0.0.0-20230726121419-3b25d923346b h1:sgn3ZU783SCgtaSJjpcVVlRqd6GSnlTLKgpAAttJvpI=
 k8s.io/utils v0.0.0-20230726121419-3b25d923346b/go.mod h1:OLgZIPagt7ERELqWJFomSt595RzquPNLL48iOWgYOg0=
 sigs.k8s.io/controller-runtime v0.17.4 h1:AMf1E0+93/jLQ13fb76S6Atwqp24EQFCmNbG84GJxew=

pkg/scheduler/fit.go

@@ -0,0 +1,124 @@
+package scheduler
+
+import (
+	"context"
+	"errors"
+
+	"k8s.io/kubernetes/pkg/scheduler/apis/config"
+	"k8s.io/kubernetes/pkg/scheduler/framework"
+	plfeature "k8s.io/kubernetes/pkg/scheduler/framework/plugins/feature"
+
+	// "k8s.io/kubernetes/pkg/scheduler/framework/plugins/interpodaffinity"
+	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/nodeaffinity"
+	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/noderesources"
+	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/nodeunschedulable"
+	"k8s.io/kubernetes/pkg/scheduler/framework/plugins/tainttoleration"
+
+	corev1 "k8s.io/api/core/v1"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+)
+
+func createNodeInfos(ctx context.Context, cli client.Client) ([]*framework.NodeInfo, error) {
+	nodes := corev1.NodeList{}
+	if err := cli.List(ctx, &nodes); err != nil {
+		return nil, err
+	}
+
+	nodeInfos := make([]*framework.NodeInfo, 0, len(nodes.Items))
+
+	for _, node := range nodes.Items {
+		nodeInfo := framework.NewNodeInfo()
+		nodeInfo.SetNode(&node)
+		pods := &corev1.PodList{}
+		if err := cli.List(ctx, pods, client.MatchingFields{"spec.nodeName": nodeInfo.Node().Name}); err != nil {
+			return nil, err
+		}
+
+		for _, pod := range pods.Items {
+			nodeInfo.AddPod(&pod)
+		}
+
+		nodeInfos = append(nodeInfos, nodeInfo)
+	}
+
+	return nodeInfos, nil
+}
+
+// WillTheyFit checks if the proposed pods will be schedulable in the cluster. The ProposedPods must have their
+// labels, tolerations, affinities and resource limits set
+func WillTheyFit(ctx context.Context, cli client.Client, proposedPods []*corev1.Pod) error {
+	usableNodes, err := createNodeInfos(ctx, cli)
+	if err != nil {
+		return err
+	}
+
+	state := framework.NewCycleState()
+
+	schedulablePlugin, err := nodeunschedulable.New(ctx, nil, nil)
+	if err != nil {
+		return err
+	}
+
+	noderesourcesPlugin, err := noderesources.NewFit(ctx, &config.NodeResourcesFitArgs{ScoringStrategy: defaultScoringStrategy}, nil, plfeature.Features{})
+	if err != nil {
+		return err
+	}
+
+	nodeaffinityPlugin, err := nodeaffinity.New(ctx, &config.NodeAffinityArgs{}, nil)
+	if err != nil {
+		return err
+	}
+
+	// interpodaffinityPlugin, err := interpodaffinity.New(ctx, &config.InterPodAffinityArgs{}, snapshot)
+	// if err != nil {
+	// 	return err
+	// }
+
+	tainttolerationPlugin, err := tainttoleration.New(ctx, nil, nil)
+	if err != nil {
+		return err
+	}
+
+	plugins := []framework.FilterPlugin{
+		noderesourcesPlugin.(framework.FilterPlugin),
+		schedulablePlugin.(framework.FilterPlugin),
+		nodeaffinityPlugin.(framework.FilterPlugin),
+		// interpodaffinityPlugin.(framework.FilterPlugin),
+		tainttolerationPlugin.(framework.FilterPlugin),
+	}
+
+NextPod:
+	for _, pod := range proposedPods {
+	NextNode:
+		for _, node := range usableNodes {
+			podInfo, err := framework.NewPodInfo(pod)
+			if err != nil {
+				return err
+			}
+
+			for _, plugin := range plugins {
+				if prefilterPlugin, ok := plugin.(framework.PreFilterPlugin); ok {
+					prefilterPlugin.PreFilter(ctx, state, podInfo.Pod)
+				}
+				status := plugin.Filter(ctx, state, podInfo.Pod, node)
+				if status.Code() != framework.Success {
+					continue NextNode
+				}
+			}
+
+			node.AddPod(pod)
+			continue NextPod
+		}
+		// Pod was never added to any node
+		return errors.New(framework.Unschedulable.String())
+	}
+	return nil
+}
+
+var defaultScoringStrategy = &config.ScoringStrategy{
+	Type: config.LeastAllocated,
+	Resources: []config.ResourceSpec{
+		{Name: "cpu", Weight: 1},
+		{Name: "memory", Weight: 1},
+	},
+}

pkg/scheduler/fit_test.go

@@ -0,0 +1,88 @@
+package scheduler
+
+import (
+	"context"
+	"strconv"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+	corev1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/client/fake"
+)
+
+func TestResources(t *testing.T) {
+	require := require.New(t)
+	ctx := context.TODO()
+	cli := createClient()
+	require.NoError(cli.Create(ctx, makeNode("node1")))
+
+	pods := []*corev1.Pod{
+		makePod("pod1"),
+	}
+	require.NoError(WillTheyFit(ctx, cli, pods))
+
+	// Lets add more pods than the node can handle
+	for i := 2; i < 20; i++ {
+		pods = append(pods, makePod("pod"+strconv.Itoa(i)))
+	}
+	require.Error(WillTheyFit(ctx, cli, pods))
+}
+
+func createClient() client.Client {
+	s := runtime.NewScheme()
+	s.AddKnownTypes(corev1.SchemeGroupVersion, &corev1.Node{})
+
+	nodeNameIndexer := client.IndexerFunc(func(obj client.Object) []string {
+		pod, ok := obj.(*corev1.Pod)
+		if !ok {
+			return nil
+		}
+		return []string{pod.Spec.NodeName}
+	})
+
+	fakeClient := fake.NewClientBuilder().WithIndex(&corev1.Pod{}, "spec.nodeName", nodeNameIndexer).Build()
+	return fakeClient
+}
+
+func makeResources(milliCPU, memory, pods int64) corev1.ResourceList {
+	return corev1.ResourceList{
+		corev1.ResourceCPU:    *resource.NewMilliQuantity(milliCPU, resource.DecimalSI),
+		corev1.ResourceMemory: *resource.NewQuantity(memory, resource.BinarySI),
+		corev1.ResourcePods:   *resource.NewQuantity(pods, resource.DecimalSI),
+	}
+}
+
+func makeNode(name string) *corev1.Node {
+	n := &corev1.Node{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: name,
+		},
+		Spec: corev1.NodeSpec{
+			Unschedulable: false,
+		},
+	}
+	n.Status.Capacity, n.Status.Allocatable = makeResources(1000, 1000, 100), makeResources(1000, 1000, 100)
+	return n
+}
+
+func makePod(name string) *corev1.Pod {
+	return &corev1.Pod{
+		ObjectMeta: metav1.ObjectMeta{
+			Name: name,
+		},
+		Spec: corev1.PodSpec{
+			Containers: []corev1.Container{
+				{
+					Resources: corev1.ResourceRequirements{
+						Requests: makeResources(100, 100, 1),
+						Limits:   makeResources(200, 200, 1),
+					},
+				},
+			},
+		},
+	}
+}