From dc1b6341b98c3d009342a878119f683bfe14b471 Mon Sep 17 00:00:00 2001 From: Nishant Totla Date: Mon, 14 Nov 2016 16:12:24 -0800 Subject: [PATCH] Refactoring code for pinning image by digest Signed-off-by: Nishant Totla --- daemon/cluster/cluster.go | 34 ++++++++++++++++++++-------------- 1 file changed, 20 insertions(+), 14 deletions(-) diff --git a/daemon/cluster/cluster.go b/daemon/cluster/cluster.go index 0caacd751b..bd4364423f 100644 --- a/daemon/cluster/cluster.go +++ b/daemon/cluster/cluster.go @@ -16,6 +16,7 @@ import ( "time" "github.com/Sirupsen/logrus" + distreference "github.com/docker/distribution/reference" apierrors "github.com/docker/docker/api/errors" apitypes "github.com/docker/docker/api/types" "github.com/docker/docker/api/types/backend" @@ -1008,16 +1009,25 @@ func (c *Cluster) GetServices(options apitypes.ServiceListOptions) ([]types.Serv // imageWithDigestString takes an image such as name or name:tag // and returns the image pinned to a digest, such as name@sha256:34234... +// Due to the difference between the docker/docker/reference, and the +// docker/distribution/reference packages, we're parsing the image twice. +// As the two packages converge, this function should be simplified. +// TODO(nishanttotla): After the packages converge, the function must +// convert distreference.Named -> distreference.Canonical, and the logic simplified. func (c *Cluster) imageWithDigestString(ctx context.Context, image string, authConfig *apitypes.AuthConfig) (string, error) { - ref, err := reference.ParseNamed(image) + ref, err := distreference.ParseNamed(image) if err != nil { return "", err } // only query registry if not a canonical reference (i.e. with digest) - if _, ok := ref.(reference.Canonical); !ok { - ref = reference.WithDefaultTag(ref) - - namedTaggedRef, ok := ref.(reference.NamedTagged) + if _, ok := ref.(distreference.Canonical); !ok { + // create a docker/docker/reference Named object because GetRepository needs it + dockerRef, err := reference.ParseNamed(image) + if err != nil { + return "", err + } + dockerRef = reference.WithDefaultTag(dockerRef) + namedTaggedRef, ok := dockerRef.(reference.NamedTagged) if !ok { return "", fmt.Errorf("unable to cast image to NamedTagged reference object") } @@ -1031,15 +1041,11 @@ func (c *Cluster) imageWithDigestString(ctx context.Context, image string, authC return "", err } - // TODO(nishanttotla): Currently, the service would lose the tag while calling WithDigest - // To prevent this, we create the image string manually, which is a bad idea in general - // This will be fixed when https://github.com/docker/distribution/pull/2044 is vendored - // namedDigestedRef, err := reference.WithDigest(ref, dscrptr.Digest) - // if err != nil { - // return "", err - // } - // return namedDigestedRef.String(), nil - return image + "@" + dscrptr.Digest.String(), nil + namedDigestedRef, err := distreference.WithDigest(distreference.EnsureTagged(ref), dscrptr.Digest) + if err != nil { + return "", err + } + return namedDigestedRef.String(), nil } else { // reference already contains a digest, so just return it return ref.String(), nil