Simple way to clone a container keeping its environment variables

clone-container.go

package main

import (
	"fmt"
	"github.com/fsouza/go-dockerclient"
	"log"
	"os"
)

func main() {
	if len(os.Args) < 3 {
		fmt.Printf("Usage: %s [ORIGINAL_CONTAINER_ID/NAME] [COMMAND...]\n", os.Args[0])
		fmt.Printf("Example: %s my-app /bin/bash\n", os.Args[0])
		os.Exit(1)
	}

	dcli, err := docker.NewClient("unix:///var/run/docker.sock")
	if err != nil {
		log.Fatal(err)
	}

	containerID := os.Args[1]
	cmd := os.Args[2:]

	baseContainer, err := dcli.InspectContainer(containerID)
	if err != nil {
		log.Fatal(err)
	}

	cloned := docker.CreateContainerOptions{
		"",
		&docker.Config{
			AttachStdin:  true,
			AttachStdout: true,
			AttachStderr: true,
			Cmd:          cmd,
			Env:          baseContainer.Config.Env,
			Image:        baseContainer.Config.Image,
			OpenStdin:    true,
			Tty:          true,
		},
	}

	container, err := dcli.CreateContainer(cloned)
	if err != nil {
		log.Fatal(err)
	}

	err = dcli.StartContainer(container.ID, container.HostConfig)
	if err != nil {
		log.Fatal(err)
	}

	fmt.Println("Now attach to the container with:\ndocker attach", container.ID)
}