Minimal k8s version (#85)

Add k8s and ClickHouse version compatibility tests. Lower minimal required k8s version.

Author: GrigoryPervakov

.github/workflows/ci.yaml

@@ -197,6 +197,58 @@ jobs:
       - name: Check Helm release status
         run: helm status my-release --namespace clickhouse-operator-system
 
+  compat-e2e-test:
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        include:
+          - name: "Minimal supported kubernetes with LTS ClickHouse release"
+            kind_version: v1.28.15
+            clickhouse_version: "25.8"
+          - name: "Latest kubernetes version with LTS ClickHouse release"
+            kind_version: v1.35.1
+            clickhouse_version: "25.8"
+          - name: "Supported ClickHouse versions"
+            kind_version: v1.30.13
+            clickhouse_version: "26.1,25.12,25.11,25.8,25.3"
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v6
+
+      - name: Set up Go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: 'go.mod'
+
+      - name: Go Mod
+        run: go mod download
+
+      - name: Build image
+        run: make docker-build IMG="clickhouse.com/clickhouse-operator:v0.0.1" BUILD_TIME=e2e
+
+      - name: Create k8s Kind Cluster
+        uses: helm/kind-action@v1
+        with:
+          cluster_name: kind
+          version: ${{ env.kind-version }}
+          config: ci/kind-cluster.config
+          node_image: "kindest/node:${{ matrix.kind_version }}"
+
+      - name: Run compatibility e2e tests
+        run: make test-compat-e2e
+        env:
+          CLICKHOUSE_VERSION: ${{ matrix.clickhouse_version }}
+
+      - name: Test Report
+        uses: dorny/test-reporter@v2
+        if: ${{ !cancelled() }}
+        with:
+          name: compat-e2e (k8s ${{ matrix.k8s_version }}${{ matrix.clickhouse_version && format(', ch {0}', matrix.clickhouse_version) || '' }})
+          badge-title: compat-e2e (k8s ${{ matrix.k8s_version }})
+          path: "**/report/*.xml"
+          reporter: java-junit
+
   e2e-test:
     needs: [ lint, bundle, build_and_test, helm-validate, helm-test ]
     strategy:
@@ -242,7 +294,7 @@ jobs:
   ci-success-check:
     name: All CI checks passed
     runs-on: ubuntu-latest
-    needs: [ lint, bundle, build_and_test, helm-validate, helm-test, e2e-test ]
+    needs: [ lint, bundle, build_and_test, helm-validate, helm-test, compat-e2e-test, e2e-test ]
     if: always()
     steps:
       - name: Determine CI status

Makefile

@@ -143,6 +143,10 @@ test-keeper-e2e: ## Run keeper e2e tests.
 test-clickhouse-e2e: ## Run clickhouse e2e tests.
 	go test ./test/e2e/ --ginkgo.label-filter clickhouse -test.timeout 30m --ginkgo.v --ginkgo.junit-report=report/junit-report.xml
 
+.PHONY: test-compat-e2e  # Run compatibility smoke tests across ClickHouse versions.
+test-compat-e2e: ## Run compatibility e2e tests.
+	go test ./test/e2e/ --ginkgo.label-filter compatibility -test.timeout 30m --ginkgo.v --ginkgo.junit-report=report/junit-report.xml
+
 .PHONY: lint
 lint: golangci-lint codespell ## Run golangci-lint linter and codespell
 	$(GOLANGCI_LINT) run

README.md

@@ -31,8 +31,8 @@ The Operator handles the full lifecycle of ClickHouse clusters, including scalin
 ### Prerequisites
 - go version v1.25.0+
 - docker version 17.03+
-- `kubectl` version v1.30.0+
-- Access to a Kubernetes v1.30.0+ cluster
+- `kubectl` version v1.28.0+
+- Access to a Kubernetes v1.28.0+ cluster
 - cert-manager installed in the cluster (for webhook certificates)
 
 ### Quick Start

api/v1alpha1/clickhousecluster_types.go

@@ -203,6 +203,8 @@ type ClickHouseCluster struct {
 
 	Spec   ClickHouseClusterSpec   `json:"spec,omitempty"`
 	Status ClickHouseClusterStatus `json:"status,omitempty"`
+
+	specificName string `json:"-"`
 }
 
 // ClickHouseReplicaID identifies a ClickHouse replica within the cluster.
@@ -306,9 +308,13 @@ func (v *ClickHouseCluster) Conditions() *[]metav1.Condition {
 	return &v.Status.Conditions
 }
 
-// SpecificName returns cluster name with resource suffix. Used to generate resource names.
+// SpecificName returns cluster name with resource suffix. Used to generate resource names that may be used in DNS.
 func (v *ClickHouseCluster) SpecificName() string {
-	return v.GetName() + "-clickhouse"
+	if v.specificName == "" {
+		v.specificName = normalizeName(v.Name) + "-clickhouse"
+	}
+
+	return v.specificName
 }
 
 // Shards returns requested number of shards in the ClickHouseCluster.

api/v1alpha1/common.go

@@ -3,6 +3,7 @@ package v1alpha1
 import (
 	"errors"
 	"fmt"
+	"strings"
 
 	corev1 "k8s.io/api/core/v1"
 )
@@ -290,6 +291,11 @@ func (s *DefaultPasswordSelector) Validate() error {
 	return nil
 }
 
+// normalizeName removes dots from name to make it valid for use as a hostname or label value, where dots are not allowed.
+func normalizeName(name string) string {
+	return strings.ReplaceAll(name, ".", "-")
+}
+
 // formatPodHostname returns hostname for the first pod in the StatefulSet.
 func formatPodHostname(stsName, serviceName, namespace, domain string) string {
 	if domain == "" {

api/v1alpha1/keepercluster_types.go

@@ -166,6 +166,8 @@ type KeeperCluster struct {
 
 	Spec   KeeperClusterSpec   `json:"spec,omitempty"`
 	Status KeeperClusterStatus `json:"status,omitempty"`
+
+	specificName string `json:"-"`
 }
 
 // KeeperReplicaID represents ClickHouse Keeper replica ID. Used for naming resources and RAFT configuration.
@@ -213,7 +215,11 @@ func (v *KeeperCluster) Conditions() *[]metav1.Condition {
 
 // SpecificName returns cluster name with resource suffix. Used to generate resource names.
 func (v *KeeperCluster) SpecificName() string {
-	return v.GetName() + "-keeper"
+	if v.specificName == "" {
+		v.specificName = normalizeName(v.Name) + "-keeper"
+	}
+
+	return v.specificName
 }
 
 // Replicas returns requested number of replicas in the cluster.

config/manifests/bases/clickhouse-operator.clusterserviceversion.yaml

@@ -170,7 +170,7 @@ spec:
   - email: operator@clickhouse.com
     name: ClickHouse Team
   maturity: alpha
-  minKubeVersion: 1.30.0
+  minKubeVersion: 1.28.0
   provider:
     name: ClickHouse Inc.
     url: https://clickhouse.com

docs/installation/helm.md

@@ -4,7 +4,7 @@ This guide covers installing the ClickHouse Operator using Helm charts.
 
 ## Prerequisites
 
-- Kubernetes cluster v1.30.0 or later
+- Kubernetes cluster v1.28.0 or later
 - Helm v3.0 or later
 - kubectl configured to communicate with your cluster
 

docs/installation/kubectl.md

@@ -4,8 +4,8 @@ This guide covers installing the ClickHouse Operator using kubectl and manifest
 
 ## Prerequisites
 
-- Kubernetes cluster v1.30.0 or later
-- kubectl v1.30.0 or later
+- Kubernetes cluster v1.28.0 or later
+- kubectl v1.28.0 or later
 - Cluster admin permissions
 
 ## Install from Release Manifests

docs/installation/olm.md

@@ -11,7 +11,7 @@ This guide covers installing the ClickHouse Operator using Operator Lifecycle Ma
 
 ## Prerequisites
 
-- Kubernetes cluster version 1.30.0 or later
+- Kubernetes cluster version 1.28.0 or later
 - kubectl configured to access your cluster
 - Cluster admin permissions
 - Installed OLM (Operator Lifecycle Manager)