Backport of [NET-6465] Consider init container resources when determi…

…ning if existing + desired deployments are equal into release/1.4.x (#3579)

* backport of commit fafd900

* backport of commit f5918d8

* backport of commit 366ebec

---------

Co-authored-by: Nathan Coleman <nathan.coleman@hashicorp.com>

control-plane/api-gateway/gatekeeper/deployment.go

@@ -6,6 +6,7 @@ package gatekeeper
 import (
 	"context"
 
+	"github.com/google/go-cmp/cmp"
 	appsv1 "k8s.io/api/apps/v1"
 	corev1 "k8s.io/api/core/v1"
 	k8serrors "k8s.io/apimachinery/pkg/api/errors"
@@ -164,13 +165,30 @@ func mergeDeployments(gcc v1alpha1.GatewayClassConfig, a, b *appsv1.Deployment)
 	return b
 }
 
+// compareDeployments determines whether two Deployments are equal for all
+// of the fields that we care about. There are some differences between a
+// Deployment returned by the Kubernetes API and one that we would create
+// in memory which are perfectly fine. We want to ignore those differences.
 func compareDeployments(a, b *appsv1.Deployment) bool {
-	// since K8s adds a bunch of defaults when we create a deployment, check that
-	// they don't differ by the things that we may actually change, namely container
-	// ports
+	if len(b.Spec.Template.Spec.InitContainers) != len(a.Spec.Template.Spec.InitContainers) {
+		return false
+	}
+
+	for i, containerA := range a.Spec.Template.Spec.InitContainers {
+		containerB := b.Spec.Template.Spec.InitContainers[i]
+		if !cmp.Equal(containerA.Resources.Limits, containerB.Resources.Limits) {
+			return false
+		}
+
+		if !cmp.Equal(containerA.Resources.Requests, containerB.Resources.Requests) {
+			return false
+		}
+	}
+
 	if len(b.Spec.Template.Spec.Containers) != len(a.Spec.Template.Spec.Containers) {
 		return false
 	}
+
 	for i, container := range a.Spec.Template.Spec.Containers {
 		otherPorts := b.Spec.Template.Spec.Containers[i].Ports
 		if len(container.Ports) != len(otherPorts) {

control-plane/api-gateway/gatekeeper/deployment_test.go

@@ -0,0 +1,216 @@
+package gatekeeper
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	appsv1 "k8s.io/api/apps/v1"
+	corev1 "k8s.io/api/core/v1"
+
+	"github.com/hashicorp/consul-k8s/control-plane/api-gateway/common"
+)
+
+func Test_compareDeployments(t *testing.T) {
+	testCases := []struct {
+		name          string
+		a, b          *appsv1.Deployment
+		shouldBeEqual bool
+	}{
+		{
+			name:          "zero-state deployments",
+			a:             &appsv1.Deployment{},
+			b:             &appsv1.Deployment{},
+			shouldBeEqual: true,
+		},
+		{
+			name: "different replicas",
+			a: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Replicas: common.PointerTo(int32(1)),
+				},
+			},
+			b: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Replicas: common.PointerTo(int32(2)),
+				},
+			},
+			shouldBeEqual: false,
+		},
+		{
+			name: "same replicas",
+			a: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Replicas: common.PointerTo(int32(1)),
+				},
+			},
+			b: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Replicas: common.PointerTo(int32(1)),
+				},
+			},
+			shouldBeEqual: true,
+		},
+		{
+			name: "different init container resources",
+			a: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							InitContainers: []corev1.Container{
+								{
+									Resources: corev1.ResourceRequirements{
+										Limits: corev1.ResourceList{
+											"cpu":    requireQuantity(t, "111m"),
+											"memory": requireQuantity(t, "111Mi"),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			b: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							InitContainers: []corev1.Container{
+								{
+									Resources: corev1.ResourceRequirements{
+										Limits: corev1.ResourceList{
+											"cpu":    requireQuantity(t, "222m"),
+											"memory": requireQuantity(t, "111Mi"),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			shouldBeEqual: false,
+		},
+		{
+			name: "same init container resources",
+			a: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							InitContainers: []corev1.Container{
+								{
+									Resources: corev1.ResourceRequirements{
+										Limits: corev1.ResourceList{
+											"cpu":    requireQuantity(t, "111m"),
+											"memory": requireQuantity(t, "111Mi"),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			b: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							InitContainers: []corev1.Container{
+								{
+									Resources: corev1.ResourceRequirements{
+										Limits: corev1.ResourceList{
+											"cpu":    requireQuantity(t, "111m"),
+											"memory": requireQuantity(t, "111Mi"),
+										},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			shouldBeEqual: true,
+		},
+		{
+			name: "different container ports",
+			a: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							Containers: []corev1.Container{
+								{
+									Ports: []corev1.ContainerPort{
+										{ContainerPort: 7070},
+										{ContainerPort: 9090},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			b: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							Containers: []corev1.Container{
+								{
+									Ports: []corev1.ContainerPort{
+										{ContainerPort: 8080},
+										{ContainerPort: 9090},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			shouldBeEqual: false,
+		},
+		{
+			name: "same container ports",
+			a: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							Containers: []corev1.Container{
+								{
+									Ports: []corev1.ContainerPort{
+										{ContainerPort: 8080},
+										{ContainerPort: 9090},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			b: &appsv1.Deployment{
+				Spec: appsv1.DeploymentSpec{
+					Template: corev1.PodTemplateSpec{
+						Spec: corev1.PodSpec{
+							Containers: []corev1.Container{
+								{
+									Ports: []corev1.ContainerPort{
+										{ContainerPort: 8080},
+										{ContainerPort: 9090},
+									},
+								},
+							},
+						},
+					},
+				},
+			},
+			shouldBeEqual: true,
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			if testCase.shouldBeEqual {
+				assert.True(t, compareDeployments(testCase.a, testCase.b), "expected deployments to be equal but they were not")
+			} else {
+				assert.False(t, compareDeployments(testCase.a, testCase.b), "expected deployments to be different but they were not")
+			}
+		})
+	}
+}