EC2 を起動したり停止したり、一覧を取得するやつ

ec2Ctrl.go

package main

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

    "github.com/aws/aws-sdk-go/aws"
    "github.com/aws/aws-sdk-go/aws/session"
    "github.com/aws/aws-sdk-go/aws/credentials"
    "github.com/aws/aws-sdk-go/service/ec2"

    "github.com/olekukonko/tablewriter"
)

var (
    argProfile = flag.String("profile", "", "Profile 名を指定.")
    argRegion = flag.String("region", "ap-northeast-1", "Region 名を指定.")
    argInstances = flag.String("instances", "", "Instance ID 又は Instance Tag 名を指定.")
    argStart = flag.Bool("start", false, "Instance を起動.")
    argStop = flag.Bool("stop", false, "Instance を停止.")
)

func outputTbl(data [][]string) {
    table := tablewriter.NewWriter(os.Stdout)
    table.SetHeader([]string{"tag:Name", "InstanceId", "InstanceType", "AZ", "PrivateIp", "PublicIp", "Status"})

    for _, value := range data {
        table.Append(value)
    }
    table.Render()
}

func awsEc2Client(profile string, region string) *ec2.EC2 {
    var config aws.Config
    if profile != "" {
        creds := credentials.NewSharedCredentials("", profile)
        config = aws.Config{Region: aws.String(region), Credentials: creds}
    } else {
        config = aws.Config{Region: aws.String(region)}
    }
    sess := session.New(&config)
    ec2Client := ec2.New(sess)
    return ec2Client
}

func listInstances(ec2Client *ec2.EC2, instances []*string) {
    params := &ec2.DescribeInstancesInput {
        InstanceIds: instances,
    }
    res, err := ec2Client.DescribeInstances(params)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(1)
    }

    allInstances := [][]string{}
    for _, r := range res.Reservations {
        for _, i := range r.Instances {
            var tag_name string
            for _, t := range i.Tags {
                if *t.Key == "Name" {
                    tag_name = *t.Value
                }
            }
            if i.PublicIpAddress == nil {
                i.PublicIpAddress = aws.String("Not assignment")
            }
            instance := []string{
                tag_name,
                *i.InstanceId,
                *i.InstanceType,
                *i.Placement.AvailabilityZone,
                *i.PrivateIpAddress,
                *i.PublicIpAddress,
                *i.State.Name,
            }
            allInstances = append(allInstances, instance)
        }
    }
    outputTbl(allInstances)
}

func startInstances(ec2Client *ec2.EC2, instances []*string) {
    params := &ec2.StartInstancesInput{
        InstanceIds: instances,
    }
    result, err := ec2Client.StartInstances(params)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(1)
    }
    for _, r := range result.StartingInstances {
        fmt.Printf("%s を起動しました.\n", *r.InstanceId)
    }
}

func stopInstances(ec2Client *ec2.EC2, instances []*string) {
    params := &ec2.StopInstancesInput{
        InstanceIds: instances,
    }
    // fmt.Println(params)
    result, err := ec2Client.StopInstances(params)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(1)
    }
    for _, r := range result.StoppingInstances {
        fmt.Printf("%s を停止しました.\n", *r.InstanceId)
    }
}

func ctrlInstances(ec2Client *ec2.EC2, instances []*string, operation string) {
    listInstances(ec2Client, instances)

    fmt.Print("上記のインスタンスを操作しますか?(y/n): ")
    var stdin string
    fmt.Scan(&stdin)
    switch stdin {
    case "y", "Y":
        switch operation {
        case "start":
            fmt.Println("EC2 を起動します.")
            startInstances(ec2Client, instances)
        case "stop":
            fmt.Println("EC2 を停止します.")
            stopInstances(ec2Client, instances)
        }
    case "n", "N":
        fmt.Println("処理を停止します.")
        os.Exit(0)
    default:
        fmt.Println("処理を停止します.")
        os.Exit(0)
    }
}

func getInstanceIds(ec2Client *ec2.EC2, instances string) []*string {
    splitedInstances := strings.Split(instances, ",")
    res, err := ec2Client.DescribeInstances(nil)
    if err != nil {
        fmt.Println(err.Error())
        os.Exit(1)
    }
    var instanceIds []*string
    for _, s := range splitedInstances {
        for _, r := range res.Reservations {
            for _, i := range r.Instances {
                for _, t := range i.Tags {
                    if *t.Key == "Name" {
                        if *t.Value == s {
                             instanceIds = append(instanceIds, aws.String(*i.InstanceId))
                        }
                    }
                }
                if *i.InstanceId == s {
                    instanceIds = append(instanceIds, aws.String(*i.InstanceId))
                }
            }
        }
    }
    return instanceIds
}

func main() {
    flag.Parse()
    //if *argProfile == "" {
    //   fmt.Println("`-profile` オプションを指定して下さい.")
    //    os.Exit(1)
    //}

    ec2Client := awsEc2Client(*argProfile, *argRegion)
    var instances []*string
    if *argInstances != "" {
        instances = getInstanceIds(ec2Client, *argInstances)
        if *argStart {
            ctrlInstances(ec2Client, instances, "start")
        } else if *argStop {
            ctrlInstances(ec2Client, instances, "stop")
        } else {
            fmt.Println("`-start` 又は `-stop` オプションを指定して下さい.")
            os.Exit(1)
        }
    } else {
        listInstances(ec2Client, nil)
    }
}