Merge pull request #866 from alexander-demicev/inplaceskeleton

Add support for in-place update contracts

Author: furkatgofurov7

.golangci.yml

@@ -103,6 +103,15 @@ linters:
       - linters:
           - gosec
         text: G114
+      - linters:
+          - gosec
+        text: G115
+      - linters:
+          - gomoddirectives
+        text: "replacement are not allowed"
+      - linters:
+          - staticcheck
+        text: SA1019
       - linters:
           - revive
         path: pkg/rke2

controlplane/config/manager/manager.yaml

@@ -25,6 +25,7 @@ spec:
         - "--diagnostics-address=${CAPRKE2_DIAGNOSTICS_ADDRESS:=:8443}"
         - "--insecure-diagnostics=${CAPRKE2_INSECURE_DIAGNOSTICS:=false}"
         - "--v=${CAPRKE2_DEBUG_LEVEL:=0}"
+        - "--feature-gates=InPlaceUpdates=${EXP_IN_PLACE_UPDATES:=false}"
         - "--concurrency=${CONCURRENCY_NUMBER:=10}"
         image: controller:latest
         name: manager

controlplane/config/rbac/role.yaml

@@ -104,3 +104,11 @@ rules:
   - list
   - patch
   - watch
+- apiGroups:
+  - runtime.cluster.x-k8s.io
+  resources:
+  - extensionconfigs
+  verbs:
+  - get
+  - list
+  - watch

controlplane/internal/controllers/inplace.go

@@ -0,0 +1,57 @@
+/*
+Copyright 2025 SUSE.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package controllers
+
+import (
+	"context"
+	"fmt"
+
+	"k8s.io/klog/v2"
+	ctrl "sigs.k8s.io/controller-runtime"
+
+	clusterv1 "sigs.k8s.io/cluster-api/api/core/v1beta2"
+
+	"github.com/rancher/cluster-api-provider-rke2/pkg/rke2"
+)
+
+func (r *RKE2ControlPlaneReconciler) tryInPlaceUpdate(
+	ctx context.Context,
+	controlPlane *rke2.ControlPlane,
+	machineToInPlaceUpdate *clusterv1.Machine,
+	machineUpToDateResult rke2.UpToDateResult,
+) (fallbackToScaleDown bool, _ ctrl.Result, _ error) {
+	// 1. Preflight checks for all machines.
+	if resultForAllMachines := r.preflightChecks(ctx, controlPlane); !resultForAllMachines.IsZero() {
+		if result := r.preflightChecks(ctx, controlPlane, machineToInPlaceUpdate); result.IsZero() {
+			return true, ctrl.Result{}, nil
+		}
+
+		return false, resultForAllMachines, nil
+	}
+
+	// 2. CanUpdateMachine check.
+	canUpdate, err := r.canUpdateMachine(ctx, machineToInPlaceUpdate, machineUpToDateResult)
+	if err != nil {
+		return false, ctrl.Result{}, fmt.Errorf("failed to determine if Machine %s can be updated in-place: %w", klog.KObj(machineToInPlaceUpdate), err)
+	}
+
+	if !canUpdate {
+		return true, ctrl.Result{}, nil
+	}
+
+	return false, ctrl.Result{}, r.triggerInPlaceUpdate(ctx, machineToInPlaceUpdate, machineUpToDateResult)
+}