From 4ffc9246e265a8e42b085db2cf0026b2d1547c6d Mon Sep 17 00:00:00 2001
From: Nick Santos <nick.santos@docker.com>
Date: Mon, 2 Sep 2024 12:04:34 -0400
Subject: [PATCH] kind: fix setup on HA clusters (#357)

when there are multiple control plane nodes,
kind creates an LB node in front of them.

before this change, we would try
to configure the registry on the LB node,
which is unnecessary and doesn't work.

fixes https://github.com/tilt-dev/ctlptl/issues/356

Signed-off-by: Nick Santos <nick.santos@docker.com>
---
 pkg/cluster/admin_kind.go      | 14 +++++++++++-
 pkg/cluster/admin_kind_test.go | 39 ++++++++++++++++++++++++++++++++++
 2 files changed, 52 insertions(+), 1 deletion(-)

diff --git a/pkg/cluster/admin_kind.go b/pkg/cluster/admin_kind.go
index 52068e5..a7b1cdb 100644
--- a/pkg/cluster/admin_kind.go
+++ b/pkg/cluster/admin_kind.go
@@ -187,7 +187,19 @@ func (a *kindAdmin) applyContainerdPatchRegistryApiV2(ctx context.Context, desir
 	if err != nil {
 		return errors.Wrap(err, "configuring registry")
 	}
-	return applyContainerdPatchRegistryApiV2(ctx, a.runner, a.iostreams, nodes, desired, registry)
+	filtered := []string{}
+	for _, node := range nodes {
+		if strings.HasSuffix(node, "external-load-balancer") {
+			// Ignore the external load balancers.
+			// These load-balance traffic to the control plane nodes.
+			// They don't need registry configuration.
+			continue
+		}
+		filtered = append(filtered, node)
+	}
+
+	return applyContainerdPatchRegistryApiV2(ctx, a.runner, a.iostreams,
+		filtered, desired, registry)
 }
 
 func (a *kindAdmin) getNodes(ctx context.Context, cluster string) ([]string, error) {
diff --git a/pkg/cluster/admin_kind_test.go b/pkg/cluster/admin_kind_test.go
index 0b62d86..fdecd58 100644
--- a/pkg/cluster/admin_kind_test.go
+++ b/pkg/cluster/admin_kind_test.go
@@ -9,6 +9,7 @@ import (
 	"k8s.io/cli-runtime/pkg/genericclioptions"
 
 	"github.com/tilt-dev/ctlptl/internal/exec"
+	"github.com/tilt-dev/ctlptl/pkg/api"
 )
 
 func TestNodeImage(t *testing.T) {
@@ -43,3 +44,41 @@ func TestNodeImage(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, "kindest/node:v1.16.9@sha256:7175872357bc85847ec4b1aba46ed1d12fa054c83ac7a8a11f5c268957fd5765", img)
 }
+
+func TestPatchRegistryConfig(t *testing.T) {
+	nodeExec := []string{}
+	runner := exec.NewFakeCmdRunner(func(argv []string) string {
+		if argv[0] == "kind" && argv[1] == "get" && argv[2] == "nodes" {
+			return `kind-external-load-balancer
+kind-control-plane
+kind-control-plane2
+`
+		}
+		if argv[0] == "docker" && argv[1] == "exec" && argv[2] == "-i" {
+			nodeExec = append(nodeExec, argv[3])
+		}
+		return ""
+	})
+	iostreams := genericclioptions.IOStreams{
+		In:     os.Stdin,
+		Out:    os.Stdout,
+		ErrOut: os.Stderr,
+	}
+	a := newKindAdmin(iostreams, runner, &fakeDockerClient{})
+	ctx := context.Background()
+
+	err := a.applyContainerdPatchRegistryApiV2(
+		ctx,
+		&api.Cluster{Name: "test-cluster"},
+		&api.Registry{Name: "test-registry"})
+	assert.NoError(t, err)
+
+	// Assert that we only executed commands
+	// in the control plane nodes, not the LB.
+	assert.Equal(t, []string{
+		"kind-control-plane",
+		"kind-control-plane",
+		"kind-control-plane2",
+		"kind-control-plane2",
+	}, nodeExec)
+}