main.go

/*
 Copyright © 2020 Dell Inc. or its subsidiaries. All Rights Reserved.

 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.
*/

package main

import (
	"context"
	"flag"
	"fmt"
	"os"
	"strings"

	"github.com/dell/gocsi"

	"github.com/dell/csi-unity/k8sutils"
	"github.com/dell/csi-unity/provider"
	"github.com/dell/csi-unity/service"
)

type leaderElection interface {
	Run() error
	WithNamespace(namespace string)
}

// main is ignored when this package is built as a go plug-in.
func main() {
	driverName := flag.String("driver-name", "", "driver name")
	driverSecret := flag.String("driver-secret", "", "driver secret yaml file")
	driverConfig := flag.String("driver-config", "", "driver config yaml file")
	enableLeaderElection := flag.Bool("leader-election", false, "boolean to enable leader election")
	leaderElectionNamespace := flag.String("leader-election-namespace", "", "namespace where leader election lease will be created")

	flag.Parse()

	if *driverName == "" {
		fmt.Fprintf(os.Stderr, "driver-name argument is mandatory")
		os.Exit(1)
	}
	service.Name = *driverName

	if *driverSecret == "" {
		fmt.Fprintf(os.Stderr, "driver-secret argument is mandatory")
		os.Exit(1)
	}
	service.DriverSecret = *driverSecret

	if *driverConfig == "" {
		fmt.Fprintf(os.Stderr, "driver-config argument is mandatory")
		os.Exit(1)
	}
	service.DriverConfig = *driverConfig

	// Always set X_CSI_DEBUG to false irrespective of what user has specified
	_ = os.Setenv(gocsi.EnvVarDebug, "false")
	// We always want to enable Request and Response logging (no reason for users to control this)
	_ = os.Setenv(gocsi.EnvVarReqLogging, "true")
	_ = os.Setenv(gocsi.EnvVarRepLogging, "true")

	kubeconfig := flag.String("kubeconfig", "", "absolute path to the kubeconfig file")
	flag.Parse()
	run := func(ctx context.Context) {
		gocsi.Run(ctx, service.Name, "A Unity Container Storage Interface (CSI) Plugin",
			usage, provider.New())
	}
	if !*enableLeaderElection {
		run(context.TODO())
	} else {
		driverName := strings.Replace(service.Name, ".", "-", -1)
		lockName := fmt.Sprintf("driver-%s", driverName)
		k8sclientset, err := k8sutils.CreateKubeClientSet(*kubeconfig)
		if err != nil {
			_, _ = fmt.Fprintf(os.Stderr, "failed to initialize leader election: %v", err)
			os.Exit(1)
		}
		// Attempt to become leader and start the driver
		k8sutils.LeaderElection(k8sclientset, lockName, *leaderElectionNamespace, run)
	}
}

const usage = `
    X_CSI_UNITY_NODENAME
        Specifies the name of the node where the Node plugin is running.
        The default value is empty.
`