🏃 Add ci-apidiff job

Author: Cecile Robert-Michon

Makefile

@@ -51,6 +51,7 @@ KUBECTL=$(TOOLS_BIN_DIR)/kubectl
 KUSTOMIZE := $(TOOLS_BIN_DIR)/kustomize
 MOCKGEN := $(TOOLS_BIN_DIR)/mockgen
 RELEASE_NOTES := $(TOOLS_BIN_DIR)/release-notes
+GO_APIDIFF := $(TOOLS_BIN_DIR)/go-apidiff
 EXP_DIR := exp
 
 # Define Docker related variables. Releases should modify and double check these vars.
@@ -148,6 +149,9 @@ $(RELEASE_NOTES): ## Build release notes
 	GOBIN=$(TOOLS_BIN_DIR) $(GO_INSTALL) sigs.k8s.io/cluster-api/hack/tools/release
 	mv $(TOOLS_BIN_DIR)/release $(RELEASE_NOTES)
 
+$(GO_APIDIFF): ## Build go-apidiff.
+	GOBIN=$(TOOLS_BIN_DIR) $(GO_INSTALL) github.com/joelanford/go-apidiff
+
 ## --------------------------------------
 ## Linting
 ## --------------------------------------

scripts/ci-apidiff.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+
+# Copyright 2020 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.
+
+set -o errexit
+set -o nounset
+set -o pipefail
+
+REPO_ROOT=$(dirname "${BASH_SOURCE[0]}")/..
+cd "${REPO_ROOT}"
+
+APIDIFF="${PWD}/hack/tools/bin/go-apidiff"
+PULL_BASE_SHA=${PULL_BASE_SHA:-$(git rev-parse origin/master)}
+
+make ${APIDIFF}
+echo "*** Running go-apidiff ***"
+
+${APIDIFF} "${PULL_BASE_SHA}" --print-compatible