chore(tools): CRD generation script moved and add validation workflow

.github/workflows/validate-crd.yml

@@ -0,0 +1,64 @@
+name: Validate CRD Generation
+
+# This workflow validates that generated CRD files are up-to-date when tool
+# dependencies change. It ensures that if go.tool.mod or go.tool.sum are updated,
+# the corresponding generated files (CRDs and deepcopy code) are also regenerated
+# and committed in the same PR.
+#
+# Why this is needed:
+# - controller-gen (from go.tool.mod) generates CRD YAML and deepcopy Go code
+# - Different versions of controller-gen may produce different output
+# - When tool versions change, generated code must be regenerated
+# - This prevents CI failures and runtime issues from stale generated code
+
+on:
+  pull_request:
+    paths:
+      - 'go.tool.mod'
+      - 'go.tool.sum'
+      - 'scripts/generate-crd.sh'
+      - '**/dnsendpoints.externaldns.k8s.io.yaml'
+
+permissions:
+  contents: read
+
+jobs:
+  validate-crd:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
+
+      - name: Set up Go
+        uses: actions/setup-go@41dfa10bad2bb2ae585af6ee5bb4d7d973ad74ed # v5.1.0
+        with:
+          go-version-file: 'go.mod'
+
+      - name: Regenerate CRDs
+        run: ./scripts/generate-crd.sh
+
+      - name: Check for uncommitted changes
+        id: check_changes
+        run: |
+          # Check if there are any changes to generated files
+          if ! git diff --quiet; then
+            echo "::error::Generated CRD files are out of sync with go.tool.mod"
+            echo ""
+            echo "The following files have uncommitted changes after running 'make crd':"
+            git diff .
+            echo ""
+            echo "This usually means:"
+            echo "1. go.tool.mod or go.tool.sum was updated (new controller-gen version)"
+            echo "2. The generated CRD files were not regenerated"
+            echo ""
+            echo "To fix this:"
+            echo "  make crd"
+            echo "  git diff ."
+            echo "  commit, push and update your PR:"
+            exit 1
+          fi
+
+      - name: Success
+        if: success()
+        run: |
+          echo "✅ Generated CRD files are up-to-date"

Makefile

@@ -16,10 +16,6 @@
 .PHONY: cover cover-html
 .DEFAULT_GOAL := build
 
-CONTROLLER_GEN := go tool -modfile=go.tool.mod  controller-gen
-YQ := go tool -modfile=go.tool.mod yq
-YAMLFMT := go tool -modfile=go.tool.mod yamlfmt
-
 cover:
 	@go test -cover -coverprofile=cover.out -v ./...
 
@@ -64,13 +60,12 @@ lint: licensecheck go-lint
 #? crd: Generates CRD using controller-gen and copy it into chart
 .PHONY: crd
 crd:
-	$(CONTROLLER_GEN) object crd:crdVersions=v1 paths="./endpoint/..."
-	$(CONTROLLER_GEN) object crd:crdVersions=v1 paths="./apis/..." output:crd:stdout | \
-		$(YAMLFMT) - | \
-		$(YQ) eval '.' --no-doc --split-exp '"./config/crd/standard/" + .metadata.name + ".yaml"'
-	$(YQ) eval '.metadata.annotations |= with_entries(select(.key | test("kubernetes\.io")))' \
-		--no-doc --split-exp '"./charts/external-dns/crds/" + .metadata.name + ".yaml"' \
-		./config/crd/standard/*.yaml
+	@./scripts/generate-crd.sh
+
+# Required while depedabot is not supporting go.tool.mod https://github.com/dependabot/dependabot-core/issues/12050
+#? tools-deps: Update go tools defined in go.tool.mod to latest versions
+tools-deps:
+	@go get -modfile=go.tool.mod tool
 
 #? test: The verify target runs tasks similar to the CI tasks, but without code coverage
 .PHONY: test

go.tool.mod

@@ -1,6 +1,6 @@
 module sigs.k8s.io/external-dns/tools
 
-go 1.25
+go 1.25.0
 
 tool (
 	github.com/google/yamlfmt/cmd/yamlfmt

scripts/generate-crd.sh

@@ -0,0 +1,91 @@
+#!/usr/bin/env bash
+# Copyright 2026 The Kubernetes Authors.
+#
+# 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.
+
+# generate-crd.sh
+#
+# This script generates Kubernetes Custom Resource Definitions (CRDs) and related
+# deepcopy code for external-dns using controller-gen from controller-tools.
+#
+# What this script does:
+# 1. Generates DeepCopy methods for types in the endpoint package
+#    - Creates zz_generated.deepcopy.go files with DeepCopy, DeepCopyInto methods
+#    - Required for Kubernetes runtime.Object interface implementation
+#
+# 2. Generates CRD manifests for API types in the apis package
+#    - Creates CRD YAML files in config/crd/standard/
+#    - Formats them using yamlfmt for consistency
+#    - Extracts individual CRD files using yq based on metadata.name
+#
+# 3. Copies CRDs to the Helm chart directory
+#    - Filters metadata.annotations to only include kubernetes.io/* annotations
+#    - Outputs to charts/external-dns/crds/ for Helm chart packaging
+#
+# Dependencies (from go.tool.mod):
+# - sigs.k8s.io/controller-tools/cmd/controller-gen - CRD and deepcopy generation
+# - github.com/google/yamlfmt/cmd/yamlfmt - YAML formatting
+# - github.com/mikefarah/yq/v4 - YAML processing and splitting
+#
+# Usage:
+#   ./scripts/generate-crd.sh
+#   make crd  # calls this script
+
+set -euo pipefail
+
+# Get the script directory
+SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+# Get the project root (parent of scripts directory)
+PROJECT_ROOT="$(cd "${SCRIPT_DIR}/.." && pwd)"
+
+cd "${PROJECT_ROOT}"
+
+# Define tool commands (using tools from go.tool.mod)
+CONTROLLER_GEN="go tool -modfile=go.tool.mod controller-gen"
+YQ="go tool -modfile=go.tool.mod yq"
+YAMLFMT="go tool -modfile=go.tool.mod yamlfmt"
+
+echo " Generating CRDs using controller-gen..."
+
+# Step 1: Generate deepcopy methods for endpoint types
+# This creates zz_generated.deepcopy.go with DeepCopy/DeepCopyInto/DeepCopyObject methods
+# The 'object' generator adds these methods for types marked with +kubebuilder:object markers
+echo "  → Generating deepcopy for endpoint package..."
+${CONTROLLER_GEN} object crd:crdVersions=v1 paths="./endpoint/..."
+
+# Clean up empty import statements from generated files
+# controller-gen sometimes adds empty import() blocks which create noise in diffs
+find ./endpoint -name "zz_generated.deepcopy.go" -exec gofmt -s -w {} \;
+
+# Step 2: Generate CRD manifests for API types
+# - Generates CRDs from Go types with kubebuilder markers
+# - Outputs to stdout, formats with yamlfmt, then splits into individual files
+# - Each CRD is saved to config/crd/standard/<crd-name>.yaml
+echo "  → Generating CRDs for apis package..."
+${CONTROLLER_GEN} object crd:crdVersions=v1 paths="./apis/..." output:crd:stdout | \
+    ${YAMLFMT} - | \
+    ${YQ} eval '.' --no-doc --split-exp '"./config/crd/standard/" + .metadata.name + ".yaml"'
+
+# Clean up empty import statements from generated files
+find ./apis -name "zz_generated.deepcopy.go" -exec gofmt -s -w {} \;
+
+# Step 3: Copy CRDs to Helm chart with filtered annotations
+# - Reads CRDs from config/crd/standard/
+# - Filters annotations to only keep kubernetes.io/* (removes controller-gen annotations)
+# - Splits and saves to charts/external-dns/crds/ for Helm chart packaging
+echo "  → Copying CRDs to chart directory..."
+${YQ} eval '.metadata.annotations |= with_entries(select(.key | test("kubernetes\.io")))' \
+    --no-doc --split-exp '"./charts/external-dns/crds/" + .metadata.name + ".yaml"' \
+    ./config/crd/standard/*.yaml
+
+echo -e "  ✅ CRD generation complete"