Separate migration of strategy configuration from the constructing and running the plugins (#999)

* Remove log level from Errors

Every error printed via Errors is expected to be important and always
printable.

* Invoke first Deschedule and then Balance extension points (breaking change)

* Separate plugin arg conversion from pluginsMap

* Seperate profile population from plugin execution

* Convert strategy params into profiles outside the main descheduling loop

Strategy params are static and do not change in time.

* Bump the internal DeschedulerPolicy to v1alpha2

Drop conversion from v1alpha1 to internal

* add tests to v1alpha1 to internal conversion

* add tests to strategyParamsToPluginArgs params wiring

* in v1alpha1 evictableNamespaces are still Namespaces

* add test passing in all params

Co-authored-by: Lucas Severo Alves <lseveroa@redhat.com>

pkg/api/types.go

@@ -19,6 +19,7 @@ package api
 import (
 	v1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
+	"k8s.io/apimachinery/pkg/runtime"
 )
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
@@ -26,24 +27,12 @@ import (
 type DeschedulerPolicy struct {
 	metav1.TypeMeta
 
-	// Strategies
-	Strategies StrategyList
+	// Profiles
+	Profiles []Profile
 
 	// NodeSelector for a set of nodes to operate over
 	NodeSelector *string
 
-	// EvictFailedBarePods allows pods without ownerReferences and in failed phase to be evicted.
-	EvictFailedBarePods *bool
-
-	// EvictLocalStoragePods allows pods using local storage to be evicted.
-	EvictLocalStoragePods *bool
-
-	// EvictSystemCriticalPods allows eviction of pods of any priority (including Kubernetes system pods)
-	EvictSystemCriticalPods *bool
-
-	// IgnorePVCPods prevents pods with PVCs from being evicted.
-	IgnorePVCPods *bool
-
 	// MaxNoOfPodsToEvictPerNode restricts maximum of pods to be evicted per node.
 	MaxNoOfPodsToEvictPerNode *uint
 
@@ -51,22 +40,6 @@ type DeschedulerPolicy struct {
 	MaxNoOfPodsToEvictPerNamespace *uint
 }
 
-type (
-	StrategyName string
-	StrategyList map[StrategyName]DeschedulerStrategy
-)
-
-type DeschedulerStrategy struct {
-	// Enabled or disabled
-	Enabled bool
-
-	// Weight
-	Weight int
-
-	// Strategy parameters
-	Params *StrategyParameters
-}
-
 // Namespaces carries a list of included/excluded namespaces
 // for which a given strategy is applicable
 type Namespaces struct {
@@ -74,64 +47,38 @@ type Namespaces struct {
 	Exclude []string
 }
 
-// Besides Namespaces only one of its members may be specified
-// TODO(jchaloup): move Namespaces ThresholdPriority and ThresholdPriorityClassName to individual strategies
-//
-//	once the policy version is bumped to v1alpha2
-type StrategyParameters struct {
-	NodeResourceUtilizationThresholds *NodeResourceUtilizationThresholds
-	NodeAffinityType                  []string
-	PodsHavingTooManyRestarts         *PodsHavingTooManyRestarts
-	PodLifeTime                       *PodLifeTime
-	RemoveDuplicates                  *RemoveDuplicates
-	FailedPods                        *FailedPods
-	IncludeSoftConstraints            bool
-	Namespaces                        *Namespaces
-	ThresholdPriority                 *int32
-	ThresholdPriorityClassName        string
-	LabelSelector                     *metav1.LabelSelector
-	NodeFit                           bool
-	IncludePreferNoSchedule           bool
-	ExcludedTaints                    []string
-}
-
 type (
 	Percentage         float64
 	ResourceThresholds map[v1.ResourceName]Percentage
 )
 
-type NodeResourceUtilizationThresholds struct {
-	UseDeviationThresholds bool
-	Thresholds             ResourceThresholds
-	TargetThresholds       ResourceThresholds
-	NumberOfNodes          int
-}
-
-type PodsHavingTooManyRestarts struct {
-	PodRestartThreshold     int32
-	IncludingInitContainers bool
-}
-
-type RemoveDuplicates struct {
-	ExcludeOwnerKinds []string
-}
-
-type PodLifeTime struct {
-	MaxPodLifeTimeSeconds *uint
-	States                []string
-
-	// Deprecated: Use States instead.
-	PodStatusPhases []string
-}
-
-type FailedPods struct {
-	ExcludeOwnerKinds       []string
-	MinPodLifetimeSeconds   *uint
-	Reasons                 []string
-	IncludingInitContainers bool
-}
-
 type PriorityThreshold struct {
 	Value *int32
 	Name  string
 }
+
+type Profile struct {
+	Name          string
+	PluginConfigs []PluginConfig
+	Plugins       Plugins
+}
+
+type PluginConfig struct {
+	Name string
+	Args runtime.Object
+}
+
+type Plugins struct {
+	PreSort           PluginSet
+	Sort              PluginSet
+	Deschedule        PluginSet
+	Balance           PluginSet
+	Evict             PluginSet
+	Filter            PluginSet
+	PreEvictionFilter PluginSet
+}
+
+type PluginSet struct {
+	Enabled  []string
+	Disabled []string
+}