Docker cleanup tool for old versions

docker-cleanup.go

package main

import (
   "flag"
	"fmt"
   "os"
	"github.com/docker/docker/api/types"
	"github.com/docker/docker/client"
	"golang.org/x/net/context"
)

var containers_tobedeleted = map[string]string{}

func main() {
   dry_run := flag.Bool("d", false, "Dry Run, don't clean any container")
   all := flag.Bool("a", true, "Clean all containers (default), if false cleans only the inactive ones")
   base_image := flag.Bool("i", false, "Clean also the related container image ")
   kill_image := flag.String("k", "", "Clean all the containers based on this image")

   flag.Parse()
   
   cli, err := client.NewEnvClient()
   if err != nil {
        panic(err)
   }

	containers, err := cli.ContainerList(context.Background(), types.ContainerListOptions{All: true})
	if err != nil {
		panic(err)
	}

   if len(containers) == 0 {
      fmt.Println("No running containers!\n(doublecheck with `docker ps`)")
      os.Exit(0)
   }

   fmt.Println("\nContainers found on this host:")
	for _, container := range containers {
      r, err := cli.ContainerInspect(context.Background(), container.ID)
      if err != nil {
           panic(err)
      }
      container_id := container.ID[:12]
      base_image := r.Image[7:19]
      running := r.State.Running
		fmt.Printf("%s - %s - %s\n",container_id,r.Name[1:],base_image)
      if ! *all {
          if ! running { 
              containers_tobedeleted[container_id] = base_image
          }
      } else {
              containers_tobedeleted[container_id] = base_image
      }
      if (base_image == *kill_image) { 
              containers_tobedeleted[container_id] = base_image
      } 
      
	}

   if *dry_run {
      fmt.Println("Dry run, exiting")
      os.Exit(0)
   }
   if len(containers_tobedeleted) > 0 {
           for c,i := range containers_tobedeleted {
		         fmt.Printf("Killing container: %s (img %s)\n",c,i)
               err := cli.ContainerRemove(context.Background(), c, types.ContainerRemoveOptions{Force: true, RemoveVolumes: true})
               if err != nil {
                   panic(err)
               }

           }
           for _,i := range containers_tobedeleted {
               if *base_image {
		             fmt.Printf("Killing image: %s\n",i)
                   _,err := cli.ImageRemove(context.Background(), i, types.ImageRemoveOptions{Force: true, PruneChildren: true})
                   if err != nil {
                      fmt.Printf("Failed to remove this image: %s\n", err)
                   }
               }     
           }

   }

}

you need to specify this environment variable DOCKER_API_VERSION to ensure the utility and the docker daemon use the same API version.