Expose assignReplicas and selectClusters function in scheduler

Signed-off-by: chaosi-zju <chaosi@zju.edu.cn>

pkg/scheduler/core/common.go

@@ -0,0 +1,73 @@
+/*
+Copyright 2021 The Karmada Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package core
+
+import (
+	"fmt"
+	"time"
+
+	clusterv1alpha1 "github.com/karmada-io/karmada/pkg/apis/cluster/v1alpha1"
+	policyv1alpha1 "github.com/karmada-io/karmada/pkg/apis/policy/v1alpha1"
+	workv1alpha2 "github.com/karmada-io/karmada/pkg/apis/work/v1alpha2"
+	"github.com/karmada-io/karmada/pkg/scheduler/core/spreadconstraint"
+	"github.com/karmada-io/karmada/pkg/scheduler/framework"
+	"github.com/karmada-io/karmada/pkg/scheduler/metrics"
+)
+
+func SelectClusters(clustersScore framework.ClusterScoreList,
+	placement *policyv1alpha1.Placement, spec *workv1alpha2.ResourceBindingSpec) ([]*clusterv1alpha1.Cluster, error) {
+	startTime := time.Now()
+	defer metrics.ScheduleStep(metrics.ScheduleStepSelect, startTime)
+
+	groupClustersInfo := spreadconstraint.GroupClustersWithScore(clustersScore, placement, spec, calAvailableReplicas)
+	return spreadconstraint.SelectBestClusters(placement, groupClustersInfo, spec.Replicas)
+}
+
+func AssignReplicas(
+	clusters []*clusterv1alpha1.Cluster,
+	placement *policyv1alpha1.Placement,
+	object *workv1alpha2.ResourceBindingSpec,
+) ([]workv1alpha2.TargetCluster, error) {
+	startTime := time.Now()
+	defer metrics.ScheduleStep(metrics.ScheduleStepAssignReplicas, startTime)
+
+	if len(clusters) == 0 {
+		return nil, fmt.Errorf("no clusters available to schedule")
+	}
+
+	if object.Replicas > 0 {
+		state := newAssignState(clusters, placement, object)
+		assignFunc, ok := assignFuncMap[state.strategyType]
+		if !ok {
+			// should never happen at present
+			return nil, fmt.Errorf("unsupported replica scheduling strategy, replicaSchedulingType: %s, replicaDivisionPreference: %s, "+
+				"please try another scheduling strategy", placement.ReplicaSchedulingType(), placement.ReplicaScheduling.ReplicaDivisionPreference)
+		}
+		assignResults, err := assignFunc(state)
+		if err != nil {
+			return nil, err
+		}
+		return removeZeroReplicasCluster(assignResults), nil
+	}
+
+	// If not workload, assign all clusters without considering replicas.
+	targetClusters := make([]workv1alpha2.TargetCluster, len(clusters))
+	for i, cluster := range clusters {
+		targetClusters[i] = workv1alpha2.TargetCluster{Name: cluster.Name}
+	}
+	return targetClusters, nil
+}

pkg/scheduler/core/generic_scheduler.go

@@ -27,7 +27,6 @@ import (
 	policyv1alpha1 "github.com/karmada-io/karmada/pkg/apis/policy/v1alpha1"
 	workv1alpha2 "github.com/karmada-io/karmada/pkg/apis/work/v1alpha2"
 	"github.com/karmada-io/karmada/pkg/scheduler/cache"
-	"github.com/karmada-io/karmada/pkg/scheduler/core/spreadconstraint"
 	"github.com/karmada-io/karmada/pkg/scheduler/framework"
 	"github.com/karmada-io/karmada/pkg/scheduler/framework/runtime"
 	"github.com/karmada-io/karmada/pkg/scheduler/metrics"
@@ -175,44 +174,10 @@ func (g *genericScheduler) prioritizeClusters(
 
 func (g *genericScheduler) selectClusters(clustersScore framework.ClusterScoreList,
 	placement *policyv1alpha1.Placement, spec *workv1alpha2.ResourceBindingSpec) ([]*clusterv1alpha1.Cluster, error) {
-	startTime := time.Now()
-	defer metrics.ScheduleStep(metrics.ScheduleStepSelect, startTime)
-
-	groupClustersInfo := spreadconstraint.GroupClustersWithScore(clustersScore, placement, spec, calAvailableReplicas)
-	return spreadconstraint.SelectBestClusters(placement, groupClustersInfo, spec.Replicas)
+	return SelectClusters(clustersScore, placement, spec)
 }
 
-func (g *genericScheduler) assignReplicas(
-	clusters []*clusterv1alpha1.Cluster,
-	placement *policyv1alpha1.Placement,
-	object *workv1alpha2.ResourceBindingSpec,
-) ([]workv1alpha2.TargetCluster, error) {
-	startTime := time.Now()
-	defer metrics.ScheduleStep(metrics.ScheduleStepAssignReplicas, startTime)
-
-	if len(clusters) == 0 {
-		return nil, fmt.Errorf("no clusters available to schedule")
-	}
-
-	if object.Replicas > 0 {
-		state := newAssignState(clusters, placement, object)
-		assignFunc, ok := assignFuncMap[state.strategyType]
-		if !ok {
-			// should never happen at present
-			return nil, fmt.Errorf("unsupported replica scheduling strategy, replicaSchedulingType: %s, replicaDivisionPreference: %s, "+
-				"please try another scheduling strategy", placement.ReplicaSchedulingType(), placement.ReplicaScheduling.ReplicaDivisionPreference)
-		}
-		assignResults, err := assignFunc(state)
-		if err != nil {
-			return nil, err
-		}
-		return removeZeroReplicasCluster(assignResults), nil
-	}
-
-	// If not workload, assign all clusters without considering replicas.
-	targetClusters := make([]workv1alpha2.TargetCluster, len(clusters))
-	for i, cluster := range clusters {
-		targetClusters[i] = workv1alpha2.TargetCluster{Name: cluster.Name}
-	}
-	return targetClusters, nil
+func (g *genericScheduler) assignReplicas(clusters []*clusterv1alpha1.Cluster, placement *policyv1alpha1.Placement,
+	object *workv1alpha2.ResourceBindingSpec) ([]workv1alpha2.TargetCluster, error) {
+	return AssignReplicas(clusters, placement, object)
 }