NO-ISSUE: Add claude md file for using the node_utils and export util functions

test/extended/node/CLAUDE.md

@@ -0,0 +1,50 @@
+# OpenShift Node E2E Tests - Tribal Knowledge
+
+## Core Principle
+
+**ALWAYS use the utility functions in `node_utils.go`** instead of implementing your own. Read that file to discover available helpers.
+
+## Key Functions & Context
+
+### Node Selection
+
+- **GetNodesByLabel** - Use this for getting a subset of the nodes. The labels must be carefully chosen.
+- **GetControlPlaneNodes** - These are the master nodes or the control plane nodes. In most clusters it will return 3 of them.
+- **GetPureWorkerNodes** - Use this to make sure that the node returned is not a control plane node.
+
+### Node Command Execution
+
+- **ExecOnNodeWithChroot** - Use this for all the root command executions inside a debug container. This can change the state of the node. Use it with caution.
+
+### Kubelet Configuration & Lifecycle
+
+- **GetKubeletConfigFromNode** - Use this to check if a kubelet configuration made at the API level has been applied to the node.
+- **CleanupDropInAndRestartKubelet** - Kubelet supports drop-in directory. If you manually drop-in a config use this to clean up.
+- **IsNodeInReadyState** - Use this to find out if the node has completed its restart and back to ready state.
+- **WaitForNodeToBeReady** - If any kubelet config is applied, use this to wait for the node to reach a ready state.
+- **RestartKubeletOnNode** - Use this when testing kubelet restarts and also in cases when there are some issues that's outside the context.
+
+### MachineConfig Operations
+
+- **WaitForMCP** - This is used when you create a new machine config and wait for it to be applied. Although parallel, if multiple nodes are involved it can take more time.
+
+## Common Mistakes to Avoid
+
+1. **Don't manually construct `oc debug` commands** - use `ExecOnNodeWithChroot()` or `ExecOnNodeWithNsenter()`
+
+2. **Don't forget to handle SNO clusters** - use `GetPureWorkerNodes()` to filter out nodes with dual roles
+
+3. **Don't skip context propagation** - always pass `ctx` to utility functions
+
+4. **Don't forget cleanup** - use `defer` or `g.AfterEach` with `CleanupDropInAndRestartKubelet()`
+
+5. **Don't ignore MCP rollouts** - after MachineConfig changes, use `WaitForMCP()` to ensure stability
+
+6. **Don't assume swap operations work with chroot** - use `ExecOnNodeWithNsenter()` for swap commands
+
+## Getting Help
+
+- Read the function documentation in `node_utils.go`
+- Look at existing tests in this directory for patterns
+- Check testdata files in `testdata/node/` for config examples
+- See `node_swap_cnv.go` for a complete example

test/extended/node/claude-docs-check.sh

@@ -0,0 +1,37 @@
+#!/bin/bash
+# Check if node_utils.go has functions not mentioned in CLAUDE.md
+
+set -e
+
+NODE_UTILS="test/extended/node/node_utils.go"
+CLAUDE_MD="test/extended/node/CLAUDE.md"
+
+# Extract ONLY exported function names from node_utils.go (start with uppercase)
+# Lowercase (unexported) helpers are intentionally not documented in CLAUDE.md
+# Matches both standalone functions and receiver methods, including digits in names
+UTILS_FUNCS=$(
+  grep -E '^[[:space:]]*func([[:space:]]+\([^)]*\))?[[:space:]]+[A-Z][A-Za-z0-9_]*[[:space:]]*\(' "$NODE_UTILS" \
+    | sed -E 's/^[[:space:]]*func([[:space:]]+\([^)]*\))?[[:space:]]+([A-Z][A-Za-z0-9_]*)[[:space:]]*\(.*/\2/' \
+    | sort -u
+)
+
+# Read CLAUDE.md once for efficiency
+CLAUDE_CONTENT=$(cat "$CLAUDE_MD")
+
+# Check each function is mentioned in CLAUDE.md (word-boundary match to avoid false positives)
+MISSING=()
+for func in $UTILS_FUNCS; do
+    if ! echo "$CLAUDE_CONTENT" | grep -Fqw "$func"; then
+        MISSING+=("  - $func()")
+    fi
+done
+
+if [ ${#MISSING[@]} -gt 0 ]; then
+    echo "⚠️  Warning: node_utils.go functions not documented in CLAUDE.md:"
+    printf '%s\n' "${MISSING[@]}"
+    echo ""
+    echo "Please update CLAUDE.md to document these utility functions."
+    exit 1
+fi
+
+echo "✅ All node_utils.go functions are documented in CLAUDE.md"

test/extended/node/node_sizing.go

@@ -151,7 +151,7 @@ var _ = g.Describe("[Suite:openshift/disruptive-longrunning][sig-node][Disruptiv
 		g.DeferCleanup(cleanupMCP)
 
 		g.By("Waiting for custom MachineConfigPool to be ready")
-		err = waitForMCP(ctx, mcClient, testMCPName, 5*time.Minute)
+		err = WaitForMCP(ctx, mcClient, testMCPName, 5*time.Minute)
 		o.Expect(err).NotTo(o.HaveOccurred(), "Custom MachineConfigPool should become ready")
 
 		verifyNodeSizingEnabledFile(oc, nodeName, "true")
@@ -193,7 +193,7 @@ var _ = g.Describe("[Suite:openshift/disruptive-longrunning][sig-node][Disruptiv
 
 			// Wait for custom MCP to be ready after cleanup
 			g.By("Waiting for custom MCP to be ready after KubeletConfig deletion")
-			waitErr := waitForMCP(cleanupCtx, mcClient, testMCPName, 5*time.Minute)
+			waitErr := WaitForMCP(cleanupCtx, mcClient, testMCPName, 5*time.Minute)
 			if apierrors.IsNotFound(waitErr) {
 				// MachineConfigPool already deleted, nothing to wait for
 			} else if waitErr != nil {
@@ -229,7 +229,7 @@ var _ = g.Describe("[Suite:openshift/disruptive-longrunning][sig-node][Disruptiv
 		}, 2*time.Minute, 10*time.Second).Should(o.BeTrue(), fmt.Sprintf("%s MCP should start updating", testMCPName))
 
 		g.By(fmt.Sprintf("Waiting for %s MCP to be ready with new configuration", testMCPName))
-		err = waitForMCP(ctx, mcClient, testMCPName, 15*time.Minute)
+		err = WaitForMCP(ctx, mcClient, testMCPName, 15*time.Minute)
 		o.Expect(err).NotTo(o.HaveOccurred(), fmt.Sprintf("%s MCP should become ready with new configuration", testMCPName))
 
 		verifyNodeSizingEnabledFile(oc, nodeName, "false")

test/extended/node/node_swap.go

@@ -45,16 +45,16 @@ var _ = g.Describe("[Jira:Node][sig-node] Node non-cnv swap configuration", func
 	// the kubelet will not use it for memory management, maintaining consistent behavior across the cluster.
 	g.It("should have correct default kubelet swap settings with worker nodes failSwapOn=false, control plane nodes failSwapOn=true, and both swapBehavior=NoSwap [OCP-86394]", ote.Informing(), func(ctx context.Context) {
 		g.By("Getting worker nodes")
-		allWorkerNodes, err := getNodesByLabel(ctx, oc, "node-role.kubernetes.io/worker")
+		allWorkerNodes, err := GetNodesByLabel(ctx, oc, "node-role.kubernetes.io/worker")
 		o.Expect(err).NotTo(o.HaveOccurred())
 		o.Expect(len(allWorkerNodes)).Should(o.BeNumerically(">", 0), "Expected at least one worker node")
 
 		// Filter out nodes that are also control plane (e.g., SNO)
-		workerNodes := getPureWorkerNodes(allWorkerNodes)
+		workerNodes := GetPureWorkerNodes(allWorkerNodes)
 
 		g.By("Validating kubelet configuration on each worker node")
 		for _, node := range workerNodes {
-			config, err := getKubeletConfigFromNode(ctx, oc, node.Name)
+			config, err := GetKubeletConfigFromNode(ctx, oc, node.Name)
 			o.Expect(err).NotTo(o.HaveOccurred(), "Failed to get kubelet config for worker node %s", node.Name)
 
 			g.By(fmt.Sprintf("Checking failSwapOn=false on worker node %s", node.Name))
@@ -74,13 +74,13 @@ var _ = g.Describe("[Jira:Node][sig-node] Node non-cnv swap configuration", func
 
 		if *controlPlaneTopology != configv1.ExternalTopologyMode {
 			g.By("Getting control plane nodes")
-			controlPlaneNodes, err := getControlPlaneNodes(ctx, oc)
+			controlPlaneNodes, err := GetControlPlaneNodes(ctx, oc)
 			o.Expect(err).NotTo(o.HaveOccurred())
 			o.Expect(len(controlPlaneNodes)).Should(o.BeNumerically(">", 0), "Expected at least one control plane node")
 
 			g.By("Validating kubelet configuration on each control plane node")
 			for _, node := range controlPlaneNodes {
-				config, err := getKubeletConfigFromNode(ctx, oc, node.Name)
+				config, err := GetKubeletConfigFromNode(ctx, oc, node.Name)
 				o.Expect(err).NotTo(o.HaveOccurred(), "Failed to get kubelet config for control plane node %s", node.Name)
 
 				g.By(fmt.Sprintf("Checking failSwapOn=true on control plane node %s", node.Name))
@@ -113,7 +113,7 @@ var _ = g.Describe("[Jira:Node][sig-node] Node non-cnv swap configuration", func
 
 		g.By("Getting initial machine config resourceVersion")
 		// Get the initial resourceVersion of the worker machine config before creating KubeletConfig
-		workerGeneratedKubeletMC, err := getWorkerGeneratedKubeletMC(ctx, mcClient)
+		workerGeneratedKubeletMC, err := GetWorkerGeneratedKubeletMC(ctx, mcClient)
 		o.Expect(err).NotTo(o.HaveOccurred(), "Failed to find worker-generated-kubelet MachineConfig")
 		initialResourceVersion := workerGeneratedKubeletMC.ResourceVersion
 		framework.Logf("Initial %s resourceVersion: %s", workerGeneratedKubeletMC.Name, initialResourceVersion)
@@ -183,21 +183,21 @@ var _ = g.Describe("[Jira:Node][sig-node] Node non-cnv swap configuration", func
 		time.Sleep(5 * time.Second)
 
 		// Check if the machine config was created or updated (compare to initial resourceVersion captured earlier)
-		workerMCAfter, err := getWorkerGeneratedKubeletMC(ctx, mcClient)
+		workerMCAfter, err := GetWorkerGeneratedKubeletMC(ctx, mcClient)
 		o.Expect(err).NotTo(o.HaveOccurred(), "Failed to find worker-generated-kubelet MachineConfig for verification")
 		o.Expect(workerMCAfter.ResourceVersion).To(o.Equal(initialResourceVersion), "Machine config %s should not be updated when failSwapOn is rejected", workerMCAfter.Name)
 		framework.Logf("Verified: %s was not updated (resourceVersion: %s)", workerMCAfter.Name, workerMCAfter.ResourceVersion)
 
 		g.By("Verifying worker nodes still have correct swap settings")
-		allWorkerNodes, err := getNodesByLabel(ctx, oc, "node-role.kubernetes.io/worker")
+		allWorkerNodes, err := GetNodesByLabel(ctx, oc, "node-role.kubernetes.io/worker")
 		o.Expect(err).NotTo(o.HaveOccurred())
 		o.Expect(len(allWorkerNodes)).Should(o.BeNumerically(">", 0), "Expected at least one worker node")
 
 		// Filter out nodes that are also control plane (e.g., SNO)
-		workerNodes := getPureWorkerNodes(allWorkerNodes)
+		workerNodes := GetPureWorkerNodes(allWorkerNodes)
 
 		for _, node := range workerNodes {
-			config, err := getKubeletConfigFromNode(ctx, oc, node.Name)
+			config, err := GetKubeletConfigFromNode(ctx, oc, node.Name)
 			o.Expect(err).NotTo(o.HaveOccurred(), "Failed to get kubelet config for worker node %s", node.Name)
 
 			g.By(fmt.Sprintf("Verifying failSwapOn=false remains unchanged on worker node %s", node.Name))