hack/e2e/ensure_kubectl.sh
#!/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 -eux

USR_LOCAL_BIN="/usr/local/bin"
MINIMUM_KUBECTL_VERSION=v1.28.1

# Ensure the kubectl tool exists and is a viable version, or installs it
verify_kubectl_version()
{
    # If kubectl is not available on the path, get it
    if ! [ -x "$(command -v kubectl)" ]; then
        if [[ "${OSTYPE}" == "linux-gnu" ]]; then
            echo "kubectl not found, installing"
            curl -LO "https://dl.k8s.io/release/${MINIMUM_KUBECTL_VERSION}/bin/linux/amd64/kubectl"
            sudo install kubectl "${USR_LOCAL_BIN}/kubectl"
        else
            echo "Missing required binary in path: kubectl"
            return 2
        fi
    fi

    local kubectl_version
    IFS=" " read -ra kubectl_version <<< "$(kubectl version --client)"
    if [[ "${MINIMUM_KUBECTL_VERSION}" != $(echo -e "${MINIMUM_KUBECTL_VERSION}\n${kubectl_version[2]}" | sort -s -t. -k 1,1 -k 2,2n -k 3,3n | head -n1) ]]; then
        cat << EOF
Detected kubectl version: ${kubectl_version[2]}.
Requires ${MINIMUM_KUBECTL_VERSION} or greater.
Please install ${MINIMUM_KUBECTL_VERSION} or later.
EOF
        return 2
    fi
}

verify_kubectl_version
