abra/pkg/client/registry.go

package client

import (
	"context"
	"fmt"
	"strings"

	"github.com/containers/image/docker"
	"github.com/containers/image/types"
	"github.com/docker/distribution/reference"
	"github.com/docker/docker/client"
	"github.com/sirupsen/logrus"
)

// GetRegistryTags retrieves all tags of an image from a container registry.
func GetRegistryTags(img reference.Named) ([]string, error) {
	var tags []string

	ref, err := docker.ParseReference(fmt.Sprintf("//%s", img))
	if err != nil {
		return tags, fmt.Errorf("failed to parse image %s, saw: %s", img, err.Error())
	}

	ctx := context.Background()
	tags, err = docker.GetRepositoryTags(ctx, &types.SystemContext{}, ref)
	if err != nil {
		return tags, err
	}

	return tags, nil
}

// GetTagDigest retrieves an image digest from a container registry.
func GetTagDigest(cl *client.Client, image reference.Named) (string, error) {
	target := fmt.Sprintf("//%s", reference.Path(image))

	ref, err := docker.ParseReference(target)
	if err != nil {
		return "", fmt.Errorf("failed to parse image %s, saw: %s", image, err.Error())
	}

	ctx := context.Background()
	img, err := ref.NewImage(ctx, nil)
	if err != nil {
		logrus.Debugf("failed to query remote registry for %s, saw: %s", image, err.Error())
		return "", fmt.Errorf("unable to read digest for %s", image)
	}
	defer img.Close()

	digest := img.ConfigInfo().Digest.String()

	if digest == "" {
		return digest, fmt.Errorf("unable to read digest for %s", image)
	}

	return strings.Split(digest, ":")[1][:7], nil
}