add makefile with coverage

.gitignore

@@ -37,3 +37,6 @@ Session.vim
 cscope.*
 
 /bazel-*
+
+# coverage output
+cover.out

Makefile

@@ -0,0 +1,26 @@
+# Copyright YEAR 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.
+
+.PHONY: cover cover-html
+
+cover:
+	$(eval PKGS := $(shell go list ./... | grep -v /vendor/))
+	$(eval PKGS_DELIM := $(shell echo $(PKGS) | sed -e 's/ /,/g'))
+	go list -f '{{if or (len .TestGoFiles) (len .XTestGoFiles)}}go test -test.v -test.timeout=120s -covermode=count -coverprofile={{.Name}}_{{len .Imports}}_{{len .Deps}}.coverprofile -coverpkg $(PKGS_DELIM) {{.ImportPath}}{{end}}' $(PKGS) | xargs -0 sh -c 
+	gocovmerge `ls *.coverprofile` > cover.out
+	rm *.coverprofile
+
+cover-html: cover
+	go tool cover -html cover.out
+