dive-zfs/main.go
2018-05-14 22:09:48 -04:00

104 lines
1.8 KiB
Go

package main
import (
"bufio"
"encoding/json"
"fmt"
"io"
"os"
"github.com/docker/docker/client"
"golang.org/x/net/context"
)
func check(e error) {
if e != nil {
panic(e)
}
}
func saveImage(readCloser io.ReadCloser) {
defer readCloser.Close()
path := "image"
if _, err := os.Stat(path); os.IsNotExist(err) {
os.Mkdir(path, 0755)
}
fo, err := os.Create("image/cache.tar")
check(err)
defer func() {
if err := fo.Close(); err != nil {
panic(err)
}
}()
w := bufio.NewWriter(fo)
buf := make([]byte, 1024)
for {
n, err := readCloser.Read(buf)
if err != nil && err != io.EOF {
panic(err)
}
if n == 0 {
break
}
if _, err := w.Write(buf[:n]); err != nil {
panic(err)
}
}
if err = w.Flush(); err != nil {
panic(err)
}
}
func main() {
ctx := context.Background()
cli, err := client.NewEnvClient()
if err != nil {
panic(err)
}
// imageID := "golang:alpine"
imageID := "die-test:latest"
fmt.Println("Saving Image...")
readCloser, err := cli.ImageSave(ctx, []string{imageID})
check(err)
saveImage(readCloser)
for {
inspect, _, err := cli.ImageInspectWithRaw(ctx, imageID)
check(err)
history, err := cli.ImageHistory(ctx, imageID)
check(err)
historyStr, err := json.MarshalIndent(history, "", " ")
check(err)
layerStr := ""
for idx, layer := range inspect.RootFS.Layers {
prefix := "├── "
if idx == len(inspect.RootFS.Layers)-1 {
prefix = "└── "
}
layerStr += fmt.Sprintf("%s%s\n", prefix, layer)
}
fmt.Printf("Image: %s\nId: %s\nParent: %s\nLayers: %d\n%sHistory: %s\n", imageID, inspect.ID, inspect.Parent, len(inspect.RootFS.Layers), layerStr, historyStr)
fmt.Println("\n")
if inspect.Parent == "" {
break
} else {
imageID = inspect.Parent
}
}
fmt.Println("See './image' for the cached image tar")
}