// mountBlob attempts to mount a blob from another repository by its digest. If
// successful, the blob is linked into the blob store and 201 Created is
// returned with the canonical url of the blob.
func (buh *blobUploadHandler) createBlobMountOption(fromRepo, mountDigest string) (distribution.BlobCreateOption, error) {
dgst, err := digest.ParseDigest(mountDigest)
if err != nil {
return nil, err
}
ref, err := reference.ParseNamed(fromRepo)
if err != nil {
return nil, err
}
canonical, err := reference.WithDigest(ref, dgst)
if err != nil {
return nil, err
}
return storage.WithMountFrom(canonical), nil
}
func TestBlobMount(t *testing.T) {
dgst, content := newRandomBlob(1024)
var m testutil.RequestResponseMap
repo := "test.example.com/uploadrepo"
sourceRepo := "test.example.com/sourcerepo"
namedRef, err := reference.ParseNamed(sourceRepo)
if err != nil {
t.Fatal(err)
}
canonicalRef, err := reference.WithDigest(namedRef, dgst)
if err != nil {
t.Fatal(err)
}
m = append(m, testutil.RequestResponseMapping{
Request: testutil.Request{
Method: "POST",
Route: "/v2/" + repo + "/blobs/uploads/",
QueryParams: map[string][]string{"from": {sourceRepo}, "mount": {dgst.String()}},
},
Response: testutil.Response{
StatusCode: http.StatusCreated,
Headers: http.Header(map[string][]string{
"Content-Length": {"0"},
"Location": {"/v2/" + repo + "/blobs/" + dgst.String()},
"Docker-Content-Digest": {dgst.String()},
}),
},
})
m = append(m, testutil.RequestResponseMapping{
Request: testutil.Request{
Method: "HEAD",
Route: "/v2/" + repo + "/blobs/" + dgst.String(),
},
Response: testutil.Response{
StatusCode: http.StatusOK,
Headers: http.Header(map[string][]string{
"Content-Length": {fmt.Sprint(len(content))},
"Last-Modified": {time.Now().Add(-1 * time.Second).Format(time.ANSIC)},
}),
},
})
e, c := testServer(m)
defer c()
ctx := context.Background()
r, err := NewRepository(ctx, repo, e, nil)
if err != nil {
t.Fatal(err)
}
l := r.Blobs(ctx)
bw, err := l.Create(ctx, storage.WithMountFrom(canonicalRef))
if bw != nil {
t.Fatalf("Expected blob writer to be nil, was %v", bw)
}
if ebm, ok := err.(distribution.ErrBlobMounted); ok {
if ebm.From.Digest() != dgst {
t.Fatalf("Unexpected digest: %s, expected %s", ebm.From.Digest(), dgst)
}
if ebm.From.Name() != sourceRepo {
t.Fatalf("Unexpected from: %s, expected %s", ebm.From.Name(), sourceRepo)
}
} else {
t.Fatalf("Unexpected error: %v, expected an ErrBlobMounted", err)
}
}