From 442423285df2dbdc73f91e8ebe25067073581e74 Mon Sep 17 00:00:00 2001
From: Sergei Zhekpisov <205766156+szhekpisov-katanox@users.noreply.github.com>
Date: Tue, 9 Jun 2026 16:49:02 +0100
Subject: [PATCH 1/2] feat: add k3d binary to image for --cluster=k3d support

---
 Dockerfile | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/Dockerfile b/Dockerfile
index 0989032b..e8df333b 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -17,6 +17,8 @@ RUN go mod download
 RUN apt-get update && apt-get install -y curl
 RUN curl -Lo ./kind https://kind.sigs.k8s.io/dl/v0.31.0/kind-linux-${TARGETARCH} && \
     chmod +x ./kind
+RUN curl -Lo ./k3d https://github.com/k3d-io/k3d/releases/download/v5.9.0/k3d-linux-${TARGETARCH} && \
+    chmod +x ./k3d
 
 # Copy source code - only what's needed
 COPY cmd/ ./cmd/
@@ -38,6 +40,7 @@ FROM gcr.io/distroless/static-debian12 AS final
 
 # Copy necessary binaries from the build stage
 COPY --from=build /argocd-diff-preview/kind /usr/local/bin/kind
+COPY --from=build /argocd-diff-preview/k3d /usr/local/bin/k3d
 COPY --from=build /argocd-diff-preview/argocd-diff-preview .
 
 # Copy docker from the docker image

From eb3d0ceccb4d2890e9cef15eadb31d6811c4c7c9 Mon Sep 17 00:00:00 2001
From: Sergei Zhekpisov <205766156+szhekpisov-katanox@users.noreply.github.com>
Date: Wed, 10 Jun 2026 11:45:13 +0100
Subject: [PATCH 2/2] fix: merge kubeconfig explicitly after k3d cluster create

k3d's end-of-create kubeconfig merge is best-effort: if it fails, k3d
logs a warning and still exits 0, and we discard its output on success.
The tool then dies later with 'No kubeconfig file found' and no clue why.

Run 'k3d kubeconfig merge --kubeconfig-merge-default' explicitly after
create so a failed merge surfaces its actual error, and log the create
output at debug level.
---
 pkg/k3d/k3d.go | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/pkg/k3d/k3d.go b/pkg/k3d/k3d.go
index e9f10de6..ea1a6875 100644
--- a/pkg/k3d/k3d.go
+++ b/pkg/k3d/k3d.go
@@ -60,6 +60,14 @@ func CreateCluster(clusterName, k3dOptions string, wait time.Duration) (time.Dur
 			log.Error().Msgf("❌ Failed to create cluster with options: %s", k3dOptions)
 		}
 		return time.Since(startTime), fmt.Errorf("failed to create cluster: %s", output)
+	} else {
+		log.Debug().Msgf("k3d cluster create output: %s", output)
+	}
+
+	// k3d's end-of-create kubeconfig merge is best-effort: on failure it only
+	// logs a warning and still exits 0. Merge explicitly so a failure surfaces.
+	if output, err := runCommand("k3d", "kubeconfig", "merge", clusterName, "--kubeconfig-merge-default"); err != nil {
+		return time.Since(startTime), fmt.Errorf("failed to write kubeconfig: %s", output)
 	}
 
 	duration := time.Since(startTime)