From 23d43aba91fc1ad4e699cbcdbffd7f1cd6231e0a Mon Sep 17 00:00:00 2001
From: Andy Pliszka <andy@isp44.com>
Date: Mon, 16 Oct 2023 10:34:33 -0400
Subject: [PATCH] feat: adds auto scale padding (#362)

* feat: adds auto scale padding

* fix: makes constant hidden
---
 internal/fullnode/pvc_builder.go      | 14 +++-
 internal/fullnode/pvc_builder_test.go | 94 +++++++++++++++++++++------
 2 files changed, 85 insertions(+), 23 deletions(-)

diff --git a/internal/fullnode/pvc_builder.go b/internal/fullnode/pvc_builder.go
index 5720265a..12f113c0 100644
--- a/internal/fullnode/pvc_builder.go
+++ b/internal/fullnode/pvc_builder.go
@@ -6,10 +6,16 @@ import (
 	cosmosv1 "github.com/strangelove-ventures/cosmos-operator/api/v1"
 	"github.com/strangelove-ventures/cosmos-operator/internal/diff"
 	"github.com/strangelove-ventures/cosmos-operator/internal/kube"
+	"gopkg.in/inf.v0"
 	corev1 "k8s.io/api/core/v1"
+	"k8s.io/apimachinery/pkg/api/resource"
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
+const (
+	snapshotGrowthFactor = 102
+)
+
 var (
 	defaultAccessModes = []corev1.PersistentVolumeAccessMode{corev1.ReadWriteOnce}
 )
@@ -79,9 +85,13 @@ func pvcResources(crd *cosmosv1.CosmosFullNode) corev1.ResourceRequirements {
 		reqs = crd.Spec.VolumeClaimTemplate.Resources
 		size = reqs.Requests[corev1.ResourceStorage]
 	)
+
 	if autoScale := crd.Status.SelfHealing.PVCAutoScale; autoScale != nil {
-		if autoScale.RequestedSize.Cmp(size) > 0 {
-			reqs.Requests[corev1.ResourceStorage] = autoScale.RequestedSize
+		requestedSize := autoScale.RequestedSize.DeepCopy()
+		newSize := requestedSize.AsDec()
+		sizeWithPadding := resource.NewDecimalQuantity(*newSize.Mul(newSize, inf.NewDec(snapshotGrowthFactor, 2)), resource.DecimalSI)
+		if sizeWithPadding.Cmp(size) > 0 {
+			reqs.Requests[corev1.ResourceStorage] = *sizeWithPadding
 		}
 	}
 	return reqs
diff --git a/internal/fullnode/pvc_builder_test.go b/internal/fullnode/pvc_builder_test.go
index 8cd9acf6..26cdb51e 100644
--- a/internal/fullnode/pvc_builder_test.go
+++ b/internal/fullnode/pvc_builder_test.go
@@ -28,6 +28,7 @@ func TestBuildPVCs(t *testing.T) {
 				Requests: corev1.ResourceList{corev1.ResourceStorage: resource.MustParse("100G")},
 			},
 		}
+
 		crd.Spec.InstanceOverrides = map[string]cosmosv1.InstanceOverridesSpec{
 			"juno-0": {},
 		}
@@ -148,30 +149,81 @@ func TestBuildPVCs(t *testing.T) {
 		}
 	})
 
-	t.Run("pvc auto scale", func(t *testing.T) {
-		for _, tt := range []struct {
-			SpecQuant, AutoScaleQuant, WantQuant string
-		}{
-			{"100G", "99G", "100G"},
-			{"100G", "101G", "101G"},
-		} {
-			crd := defaultCRD()
-			crd.Spec.Replicas = 1
-			crd.Spec.VolumeClaimTemplate = cosmosv1.PersistentVolumeClaimSpec{
-				Resources: corev1.ResourceRequirements{
-					Requests: corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.SpecQuant)},
-				},
-			}
-			crd.Status.SelfHealing.PVCAutoScale = &cosmosv1.PVCAutoScaleStatus{
-				RequestedSize: resource.MustParse(tt.AutoScaleQuant),
+	t.Run("pvc auto scale with padding", func(t *testing.T) {
+		t.Run("given auto scale size less then current size", func(t *testing.T) {
+			for _, tt := range []struct {
+				SpecQuant, AutoScaleQuant, WantQuant string
+			}{
+				{"100G", "97G", "100G"},
+			} {
+				crd := defaultCRD()
+				crd.Spec.Replicas = 1
+				crd.Spec.VolumeClaimTemplate = cosmosv1.PersistentVolumeClaimSpec{
+					Resources: corev1.ResourceRequirements{
+						Requests: corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.SpecQuant)},
+					},
+				}
+				crd.Status.SelfHealing.PVCAutoScale = &cosmosv1.PVCAutoScaleStatus{
+					RequestedSize: resource.MustParse(tt.AutoScaleQuant),
+				}
+
+				pvcs := BuildPVCs(&crd)
+				require.Len(t, pvcs, 1, tt)
+
+				want := corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.WantQuant)}
+				require.Equal(t, want.Storage().Value(), pvcs[0].Object().Spec.Resources.Requests.Storage().Value(), tt)
 			}
+		})
 
-			pvcs := BuildPVCs(&crd)
-			require.Len(t, pvcs, 1, tt)
+		t.Run("given auto scale size equal to current size", func(t *testing.T) {
+			for _, tt := range []struct {
+				SpecQuant, AutoScaleQuant, WantQuant string
+			}{
+				{"102G", "100G", "102G"},
+			} {
+				crd := defaultCRD()
+				crd.Spec.Replicas = 1
+				crd.Spec.VolumeClaimTemplate = cosmosv1.PersistentVolumeClaimSpec{
+					Resources: corev1.ResourceRequirements{
+						Requests: corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.SpecQuant)},
+					},
+				}
+				crd.Status.SelfHealing.PVCAutoScale = &cosmosv1.PVCAutoScaleStatus{
+					RequestedSize: resource.MustParse(tt.AutoScaleQuant),
+				}
+
+				pvcs := BuildPVCs(&crd)
+				require.Len(t, pvcs, 1, tt)
+
+				want := corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.WantQuant)}
+				require.Equal(t, want, pvcs[0].Object().Spec.Resources.Requests, tt)
+			}
+		})
 
-			want := corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.WantQuant)}
-			require.Equal(t, want, pvcs[0].Object().Spec.Resources.Requests, tt)
-		}
+		t.Run("given auto scale size greater then current size", func(t *testing.T) {
+			for _, tt := range []struct {
+				SpecQuant, AutoScaleQuant, WantQuant string
+			}{
+				{"100G", "100G", "102G"},
+			} {
+				crd := defaultCRD()
+				crd.Spec.Replicas = 1
+				crd.Spec.VolumeClaimTemplate = cosmosv1.PersistentVolumeClaimSpec{
+					Resources: corev1.ResourceRequirements{
+						Requests: corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.SpecQuant)},
+					},
+				}
+				crd.Status.SelfHealing.PVCAutoScale = &cosmosv1.PVCAutoScaleStatus{
+					RequestedSize: resource.MustParse(tt.AutoScaleQuant),
+				}
+
+				pvcs := BuildPVCs(&crd)
+				require.Len(t, pvcs, 1, tt)
+
+				want := corev1.ResourceList{corev1.ResourceStorage: resource.MustParse(tt.WantQuant)}
+				require.Equal(t, want.Storage().Value(), pvcs[0].Object().Spec.Resources.Requests.Storage().Value(), tt)
+			}
+		})
 	})
 
 	test.HasTypeLabel(t, func(crd cosmosv1.CosmosFullNode) []map[string]string {