docker-hub-tag-list.go

package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"io/ioutil"
	"net/http"
	"time"
)

type ImageInfo struct {
	Count    int         `json:"count"`
	Next     string      `json:"next"`
	Previous interface{} `json:"previous"`
	Results  []struct {
		Creator int         `json:"creator"`
		ID      int         `json:"id"`
		ImageID interface{} `json:"image_id"`
		Images  []struct {
			Architecture string      `json:"architecture"`
			Features     string      `json:"features"`
			Variant      interface{} `json:"variant"`
			Digest       string      `json:"digest"`
			Os           string      `json:"os"`
			OsFeatures   string      `json:"os_features"`
			OsVersion    interface{} `json:"os_version"`
			Size         int64       `json:"size"`
			Status       string      `json:"status"`
			LastPulled   interface{} `json:"last_pulled"`
			LastPushed   time.Time   `json:"last_pushed"`
		} `json:"images"`
		LastUpdated         time.Time   `json:"last_updated"`
		LastUpdater         int         `json:"last_updater"`
		LastUpdaterUsername string      `json:"last_updater_username"`
		Name                string      `json:"name"`
		Repository          int         `json:"repository"`
		FullSize            int64       `json:"full_size"`
		V2                  bool        `json:"v2"`
		TagStatus           string      `json:"tag_status"`
		TagLastPulled       interface{} `json:"tag_last_pulled"`
		TagLastPushed       time.Time   `json:"tag_last_pushed"`
	} `json:"results"`
}

var emptyImageInfo = &ImageInfo{}

func (i *ImageInfo) Reset() {
	*i = *emptyImageInfo
}

func fetch(repo string) []byte {
	resp, err := http.Get("https://registry.hub.docker.com/v2/repositories/" + repo + "/tags/")
	if err != nil {
		fmt.Println("Error:", err)
	}
	body, err := ioutil.ReadAll(resp.Body)
	return body
}

func fetchnext(url string) []byte {
	resp, err := http.Get(url)
	if err != nil {
		fmt.Println("Error:", err)
	}
	body, err := ioutil.ReadAll(resp.Body)
	return body
}

func main() {
	var image ImageInfo
	var repo string

	flag.StringVar(&repo, "r", "", "")
	flag.Parse()

	body := fetch(repo)
	json.Unmarshal(body, &image)
	for _, version := range image.Results {
		fmt.Println(version.Name)
	}
	for image.Next != "" {
		body = fetchnext(image.Next)
		image.Reset()
		json.Unmarshal(body, &image)
		for _, version := range image.Results {
			fmt.Println(version.Name)
		}

	}
}