Add support for custom metrics for HPA (#2423)

* Add support for custom metrics for HPA
* Cleanup TargetCPUPercent references from possible places
* HPA v2beta has 80% default  cpu limit if not set

Signed-off-by: Sanket Sudake <sanketsudake@gmail.com>

pkg/apis/core/v1/types.go

@@ -17,6 +17,7 @@ limitations under the License.
 package v1
 
 import (
+	asv2beta2 "k8s.io/api/autoscaling/v2beta2"
 	apiv1 "k8s.io/api/core/v1"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"k8s.io/apimachinery/pkg/runtime/schema"
@@ -459,22 +460,36 @@ type (
 		// +optional
 		ExecutorType ExecutorType `json:"ExecutorType"`
 
-		// +optional
 		// This is only for newdeploy to set up minimum replicas of deployment.
+		// +optional
 		MinScale int `json:"MinScale"`
 
-		// +optional
 		// This is only for newdeploy to set up maximum replicas of deployment.
+		// +optional
 		MaxScale int `json:"MaxScale"`
 
+		// Deprecated: use hpaMetrics instead.
+		// This is only for executor type newdeploy and container to set up target CPU utilization of HPA.
+		// Applicable for executor type newdeploy and container.
 		// +optional
-		// This is only for newdeploy to set up target CPU utilization of HPA.
 		TargetCPUPercent int `json:"TargetCPUPercent"`
 
-		// +optional
 		// This is the timeout setting for executor to wait for pod specialization.
+		// +optional
 		SpecializationTimeout int `json:"SpecializationTimeout"`
+
+		// hpaMetrics is the list of metrics used to determine the desired replica count of the Deployment
+		// created for the function.
+		// Applicable for executor type newdeploy and container.
+		// +optional
+		Metrics []asv2beta2.MetricSpec `json:"hpaMetrics,omitempty"`
+
+		// hpaBehavior is the behavior of HPA when scaling in up/down direction.
+		// Applicable for executor type newdeploy and container.
+		// +optional
+		Behavior *asv2beta2.HorizontalPodAutoscalerBehavior `json:"hpaBehavior,omitempty"`
 	}
+
 	// FunctionReferenceType refers to type of Function
 	FunctionReferenceType string
 

pkg/apis/core/v1/validation.go

@@ -20,6 +20,7 @@ import (
 	"errors"
 	"fmt"
 	"net/http"
+	"reflect"
 	"regexp"
 	"strings"
 
@@ -270,7 +271,7 @@ func (spec FunctionSpec) Validate() error {
 		result = multierror.Append(result, c.Validate())
 	}
 
-	if spec.InvokeStrategy != (InvokeStrategy{}) {
+	if !reflect.DeepEqual(spec.InvokeStrategy, InvokeStrategy{}) {
 		result = multierror.Append(result, spec.InvokeStrategy.Validate())
 	}
 
@@ -309,7 +310,7 @@ func (es ExecutionStrategy) Validate() error {
 		result = multierror.Append(result, MakeValidationErr(ErrorUnsupportedType, "ExecutionStrategy.ExecutorType", es.ExecutorType, "not a valid executor type"))
 	}
 
-	if es.ExecutorType == ExecutorTypeNewdeploy {
+	if es.ExecutorType == ExecutorTypeNewdeploy || es.ExecutorType == ExecutorTypeContainer {
 		if es.MinScale < 0 {
 			result = multierror.Append(result, MakeValidationErr(ErrorInvalidValue, "ExecutionStrategy.MinScale", es.MinScale, "minimum scale must be greater than or equal to 0"))
 		}
@@ -322,7 +323,7 @@ func (es ExecutionStrategy) Validate() error {
 			result = multierror.Append(result, MakeValidationErr(ErrorInvalidValue, "ExecutionStrategy.MaxScale", es.MaxScale, "maximum scale must be greater than or equal to minimum scale"))
 		}
 
-		if es.TargetCPUPercent <= 0 || es.TargetCPUPercent > 100 {
+		if es.TargetCPUPercent < 0 || es.TargetCPUPercent > 100 {
 			result = multierror.Append(result, MakeValidationErr(ErrorInvalidValue, "ExecutionStrategy.TargetCPUPercent", es.TargetCPUPercent, "TargetCPUPercent must be a value between 1 - 100"))
 		}
 

pkg/apis/core/v1/zz_generated.deepcopy.go

@@ -22,6 +22,7 @@ limitations under the License.
 package v1
 
 import (
+	v2beta2 "k8s.io/api/autoscaling/v2beta2"
 	corev1 "k8s.io/api/core/v1"
 	runtime "k8s.io/apimachinery/pkg/runtime"
 )
@@ -313,6 +314,18 @@ func (in *EnvironmentSpec) DeepCopy() *EnvironmentSpec {
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *ExecutionStrategy) DeepCopyInto(out *ExecutionStrategy) {
 	*out = *in
+	if in.Metrics != nil {
+		in, out := &in.Metrics, &out.Metrics
+		*out = make([]v2beta2.MetricSpec, len(*in))
+		for i := range *in {
+			(*in)[i].DeepCopyInto(&(*out)[i])
+		}
+	}
+	if in.Behavior != nil {
+		in, out := &in.Behavior, &out.Behavior
+		*out = new(v2beta2.HorizontalPodAutoscalerBehavior)
+		(*in).DeepCopyInto(*out)
+	}
 	return
 }
 
@@ -442,7 +455,7 @@ func (in *FunctionSpec) DeepCopyInto(out *FunctionSpec) {
 		copy(*out, *in)
 	}
 	in.Resources.DeepCopyInto(&out.Resources)
-	out.InvokeStrategy = in.InvokeStrategy
+	in.InvokeStrategy.DeepCopyInto(&out.InvokeStrategy)
 	if in.IdleTimeout != nil {
 		in, out := &in.IdleTimeout, &out.IdleTimeout
 		*out = new(int)
@@ -580,7 +593,7 @@ func (in *IngressConfig) DeepCopy() *IngressConfig {
 // DeepCopyInto is an autogenerated deepcopy function, copying the receiver, writing into out. in must be non-nil.
 func (in *InvokeStrategy) DeepCopyInto(out *InvokeStrategy) {
 	*out = *in
-	out.ExecutionStrategy = in.ExecutionStrategy
+	in.ExecutionStrategy.DeepCopyInto(&out.ExecutionStrategy)
 	return
 }
 

pkg/apis/core/v1/zz_generated.swagger_doc_generated.go

@@ -143,8 +143,10 @@ var map_ExecutionStrategy = map[string]string{
 	"ExecutorType":          "ExecutorType is the executor type of function used. Defaults to \"poolmgr\".\n\nAvailable value:\n - poolmgr\n - newdeploy\n - container",
 	"MinScale":              "This is only for newdeploy to set up minimum replicas of deployment.",
 	"MaxScale":              "This is only for newdeploy to set up maximum replicas of deployment.",
-	"TargetCPUPercent":      "This is only for newdeploy to set up target CPU utilization of HPA.",
+	"TargetCPUPercent":      "Deprecated: use hpaMetrics instead. This is only for executor type newdeploy and container to set up target CPU utilization of HPA. Applicable for executor type newdeploy and container.",
 	"SpecializationTimeout": "This is the timeout setting for executor to wait for pod specialization.",
+	"hpaMetrics":            "hpaMetrics is the list of metrics used to determine the desired replica count of the Deployment created for the function. Applicable for executor type newdeploy and container.",
+	"hpaBehavior":           "hpaBehavior is the behavior of HPA when scaling in up/down direction. Applicable for executor type newdeploy and container.",
 }
 
 func (ExecutionStrategy) SwaggerDoc() map[string]string {