constellation/cli/internal/image/image.go

158 lines
4.1 KiB
Go

/*
Copyright (c) Edgeless Systems GmbH
SPDX-License-Identifier: AGPL-3.0-only
*/
package image
import (
"context"
"encoding/json"
"errors"
"fmt"
"io/fs"
"regexp"
"github.com/edgelesssys/constellation/v2/internal/cloud/cloudprovider"
"github.com/edgelesssys/constellation/v2/internal/config"
"github.com/edgelesssys/constellation/v2/internal/versionsapi"
"github.com/edgelesssys/constellation/v2/internal/versionsapi/fetcher"
"github.com/spf13/afero"
)
// Fetcher fetches image references using a lookup table.
type Fetcher struct {
fetcher versionsAPIImageInfoFetcher
fs *afero.Afero
}
// New returns a new image fetcher.
func New() *Fetcher {
return &Fetcher{
fetcher: fetcher.NewFetcher(),
fs: &afero.Afero{Fs: afero.NewOsFs()},
}
}
// FetchReference fetches the image reference for a given image version uid, CSP and image variant.
func (f *Fetcher) FetchReference(ctx context.Context, config *config.Config) (string, error) {
provider := config.GetProvider()
variant, err := variant(provider, config)
if err != nil {
return "", err
}
ver, err := versionsapi.NewVersionFromShortPath(config.Image, versionsapi.VersionKindImage)
if err != nil {
return "", err
}
imgInfoReq := versionsapi.ImageInfo{
Ref: ver.Ref,
Stream: ver.Stream,
Version: ver.Version,
}
url, err := imgInfoReq.URL()
if err != nil {
return "", err
}
imgInfo, err := getFromFile(f.fs, imgInfoReq)
if err != nil && errors.Is(err, fs.ErrNotExist) {
imgInfo, err = f.fetcher.FetchImageInfo(ctx, imgInfoReq)
}
var notFoundErr *fetcher.NotFoundError
switch {
case errors.As(err, &notFoundErr):
overridePath := imageInfoFilename(imgInfoReq)
return "", fmt.Errorf("image info file not found locally at %q or remotely at %s", overridePath, url)
case err != nil:
return "", err
}
if err := imgInfo.Validate(); err != nil {
return "", fmt.Errorf("validating image info file: %w", err)
}
return getReferenceFromImageInfo(provider, variant, imgInfo)
}
// variant returns the image variant for a given CSP and configuration.
func variant(provider cloudprovider.Provider, config *config.Config) (string, error) {
switch provider {
case cloudprovider.AWS:
return config.Provider.AWS.Region, nil
case cloudprovider.Azure:
if *config.Provider.Azure.ConfidentialVM {
return "cvm", nil
}
return "trustedlaunch", nil
case cloudprovider.GCP:
return "sev-es", nil
case cloudprovider.QEMU:
return "default", nil
default:
return "", fmt.Errorf("unsupported provider: %s", provider)
}
}
func getFromFile(fs *afero.Afero, imgInfo versionsapi.ImageInfo) (versionsapi.ImageInfo, error) {
fileName := imageInfoFilename(imgInfo)
raw, err := fs.ReadFile(fileName)
if err != nil {
return versionsapi.ImageInfo{}, err
}
var newInfo versionsapi.ImageInfo
if err := json.Unmarshal(raw, &newInfo); err != nil {
return versionsapi.ImageInfo{}, fmt.Errorf("decoding image info file: %w", err)
}
return newInfo, nil
}
var filenameReplaceRegexp = regexp.MustCompile(`([^a-zA-Z0-9.-])`)
func imageInfoFilename(imgInfo versionsapi.ImageInfo) string {
path := imgInfo.JSONPath()
return filenameReplaceRegexp.ReplaceAllString(path, "_")
}
// getReferenceFromImageInfo returns the image reference for a given CSP and image variant.
func getReferenceFromImageInfo(provider cloudprovider.Provider, variant string, imgInfo versionsapi.ImageInfo,
) (string, error) {
var providerList map[string]string
switch provider {
case cloudprovider.AWS:
providerList = imgInfo.AWS
case cloudprovider.Azure:
providerList = imgInfo.Azure
case cloudprovider.GCP:
providerList = imgInfo.GCP
case cloudprovider.QEMU:
providerList = imgInfo.QEMU
default:
return "", fmt.Errorf("image not available in image info for CSP %q", provider.String())
}
if providerList == nil {
return "", fmt.Errorf("image not available in image info for CSP %q", provider.String())
}
ref, ok := providerList[variant]
if !ok {
return "", fmt.Errorf("image not available in image info for variant %q", variant)
}
return ref, nil
}
type versionsAPIImageInfoFetcher interface {
FetchImageInfo(ctx context.Context, imageInfo versionsapi.ImageInfo) (versionsapi.ImageInfo, error)
}