added logic to check to see if the replicas has been modified before …

…overriding

internal/k8s/gatewayclient/gatewayclient.go

@@ -38,6 +38,7 @@ type Client interface {
 	GetTCPRoutesInNamespace(ctx context.Context, ns string) ([]gateway.TCPRoute, error)
 	GetMeshService(ctx context.Context, key types.NamespacedName) (*apigwv1alpha1.MeshService, error)
 	GetNamespace(ctx context.Context, key types.NamespacedName) (*core.Namespace, error)
+	GetDeployment(ctx context.Context, key types.NamespacedName) (*apps.Deployment, error)
 
 	// finalizer helpers
 
@@ -230,6 +231,17 @@ func (g *gatewayClient) GetService(ctx context.Context, key types.NamespacedName
 	return svc, nil
 }
 
+func (g *gatewayClient) GetDeployment(ctx context.Context, key types.NamespacedName) (*apps.Deployment, error) {
+	depl := &apps.Deployment{}
+	if err := g.Client.Get(ctx, key, depl); err != nil {
+		if k8serrors.IsNotFound(err) {
+			return nil, nil
+		}
+		return nil, NewK8sError(err)
+	}
+	return depl, nil
+}
+
 func (g *gatewayClient) GetSecret(ctx context.Context, key types.NamespacedName) (*core.Secret, error) {
 	secret := &core.Secret{}
 	if err := g.Client.Get(ctx, key, secret); err != nil {

internal/k8s/reconciler/gateway.go

@@ -464,7 +464,12 @@ func (g *K8sGateway) ensureDeploymentExists(ctx context.Context) error {
 
 	deployment := g.deploymentBuilder.Build()
 	mutated := deployment.DeepCopy()
-	mutated = apigwv1alpha1.MergeDeployment(deployment, mutated)
+
+	currentDeployment, err := g.client.GetDeployment(ctx, types.NamespacedName{Namespace: deployment.Namespace, Name: deployment.Name})
+	if err != nil {
+		return err
+	}
+	mutated = apigwv1alpha1.MergeDeployment(deployment, mutated, currentDeployment.Spec.Replicas)
 
 	if updated, err := g.client.CreateOrUpdateDeployment(ctx, mutated, func() error {
 		return g.client.SetControllerOwnership(g.gateway, mutated)

pkg/apis/v1alpha1/types.go

@@ -205,10 +205,15 @@ func compareServices(a, b *corev1.Service) bool {
 // MergeDeploymentmerges a gateway deployment a onto b and returns b, overriding all of
 // the fields that we'd normally set for a service deployment. It does not attempt
 // to change the service type
-func MergeDeployment(a, b *appsv1.Deployment) *appsv1.Deployment {
+func MergeDeployment(a, b *appsv1.Deployment, currentReplicas *int32) *appsv1.Deployment {
 	if !compareDeployments(a, b) {
 		b.Spec.Template = a.Spec.Template
-		b.Spec.Replicas = a.Spec.Replicas
+
+		//Dont override if replicas have already been set on deployment
+		//TODO this logic will likely need to be updated as part of CAPIGW-137
+		if currentReplicas == nil {
+			b.Spec.Replicas = a.Spec.Replicas
+		}
 	}
 
 	return b