func (s *imageURLSuite) TestImageDownloadURLUnsupportedContainer(c *gc.C) {
_, err := container.ImageDownloadURL(instance.KVM, "trusty", "amd64", "released", "")
c.Assert(err, gc.ErrorMatches, "unsupported container .*")
}
// fetchAndCacheLxcImage fetches an lxc image tarball from http://cloud-images.ubuntu.com
// and caches it in the state blobstore.
func (h *imagesDownloadHandler) fetchAndCacheLxcImage(storage imagestorage.Storage, envuuid, series, arch string) error {
cfg, err := h.state.EnvironConfig()
if err != nil {
return errors.Trace(err)
}
imageURL, err := container.ImageDownloadURL(instance.LXC, series, arch, cfg.CloudImageBaseURL())
if err != nil {
return errors.Annotatef(err, "cannot determine LXC image URL: %v", err)
}
// Fetch the image checksum.
imageFilename := path.Base(imageURL)
shafile := strings.Replace(imageURL, imageFilename, "SHA256SUMS", -1)
shaResp, err := http.Get(shafile)
if err != nil {
return errors.Annotatef(err, "cannot get sha256 data from %v", shafile)
}
defer shaResp.Body.Close()
shaInfo, err := ioutil.ReadAll(shaResp.Body)
if err != nil {
return errors.Annotatef(err, "cannot read sha256 data from %v", shafile)
}
// The sha file has lines like:
// "<checksum> *<imageFilename>"
checksum := ""
for _, line := range strings.Split(string(shaInfo), "\n") {
parts := strings.Split(line, "*")
if len(parts) != 2 {
continue
}
if parts[1] == imageFilename {
checksum = strings.TrimSpace(parts[0])
break
}
}
if checksum == "" {
return errors.Errorf("cannot find sha256 checksum for %v", imageFilename)
}
// Fetch the image.
logger.Debugf("fetching LXC image from: %v", imageURL)
resp, err := http.Get(imageURL)
if err != nil {
return errors.Annotatef(err, "cannot get image from %v", imageURL)
}
logger.Debugf("lxc image has size: %v bytes", resp.ContentLength)
defer resp.Body.Close()
hash := sha256.New()
// Set up a chain of readers to pull in the data and calculate the checksum.
rdr := io.TeeReader(resp.Body, hash)
metadata := &imagestorage.Metadata{
EnvUUID: envuuid,
Kind: string(instance.LXC),
Series: series,
Arch: arch,
Size: resp.ContentLength,
SHA256: checksum,
SourceURL: imageURL,
}
// Stream the image to storage.
err = networkOperationWitDefaultRetries(func() error {
return storage.AddImage(rdr, metadata)
}, "add os image to blobstore")()
if err != nil {
return errors.Trace(err)
}
// Better check the downloaded image checksum.
downloadChecksum := fmt.Sprintf("%x", hash.Sum(nil))
if downloadChecksum != checksum {
err := networkOperationWitDefaultRetries(func() error {
return storage.DeleteImage(metadata)
}, "delete os image from blobstore")()
if err != nil {
logger.Errorf("checksum mismatch, failed to delete image from storage: %v", err)
}
return errors.Errorf("download checksum mismatch %s != %s", downloadChecksum, checksum)
}
return nil
}
func (s *imageURLSuite) TestImageDownloadURLOtherBase(c *gc.C) {
imageDownloadURL, err := container.ImageDownloadURL(instance.LXC, "trusty", "amd64", "released", "other://cloud-images")
c.Assert(err, gc.IsNil)
c.Assert(imageDownloadURL, gc.Equals, "other://cloud-images/trusty-released-amd64-root.tar.gz")
}