Test dependencies

hack/ensure-go.sh

@@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+
+# Copyright 2021 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
+
+[[ -n ${DEBUG:-} ]] && set -o xtrace
+
+# Ensure the go tool exists and is a viable version.
+verify_go_version() {
+  if [[ -z "$(command -v go)" ]]; then
+    if [[ "${INSTALL_GO:-"true"}" == "true" ]]; then
+      curl -sSL https://golang.org/dl/go${GO_VERSION:-"1.16.3"}.linux-amd64.tar.gz | tar -C /usr/local -xzf -
+      export PATH=/usr/local/go/bin:$PATH
+      export PATH=$(go env GOPATH)/bin:$PATH
+    else
+      cat <<EOF
+Can't find 'go' in PATH, please fix and retry.
+See http://golang.org/doc/install for installation instructions.
+EOF
+      return 2
+    fi
+  fi
+
+  local go_version
+  IFS=" " read -ra go_version <<< "$(go version)"
+  local minimum_go_version
+  minimum_go_version=1.16.0
+  if [[ "${minimum_go_version}" != $(echo -e "${minimum_go_version}\n${go_version[2]}" | sort -s -t. -k 1,1 -k 2,2n -k 3,3n | head -n1) && "${go_version[2]}" != "devel" ]]; then
+    cat <<EOF
+Detected go version: ${go_version[*]}.
+Kubernetes requires ${minimum_go_version} or greater.
+Please install ${minimum_go_version} or later.
+EOF
+    return 2
+  fi
+}
+
+echo "Checking if go is available"
+verify_go_version
+
+go version
+
+# Explicitly opt into go modules, even though we're inside a GOPATH directory
+export GO111MODULE=on