1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
moby--moby/image/image_test.go
Tonis Tiigi 504e67b867 Calculate hash based image IDs on pull
Generate a hash chain involving the image configuration, layer digests,
and parent image hashes. Use the digests to compute IDs for each image
in a manifest, instead of using the remotely specified IDs.

To avoid breaking users' caches, check for images already in the graph
under old IDs, and avoid repulling an image if the version on disk under
the legacy ID ends up with the same digest that was computed from the
manifest for that image.

When a calculated ID already exists in the graph but can't be verified,
continue trying SHA256(digest) until a suitable ID is found.

"save" and "load" are not changed to use a similar scheme. "load" will
preserve the IDs present in the tar file.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
2015-10-12 10:51:28 -07:00

55 lines
1.7 KiB
Go

package image
import (
"bytes"
"io/ioutil"
"testing"
"github.com/docker/distribution/digest"
)
var fixtures = []string{
"fixtures/pre1.9",
"fixtures/post1.9",
}
func loadFixtureFile(t *testing.T, path string) []byte {
fileData, err := ioutil.ReadFile(path)
if err != nil {
t.Fatalf("error opening %s: %v", path, err)
}
return bytes.TrimSpace(fileData)
}
// TestMakeImageConfig makes sure that MakeImageConfig returns the expected
// canonical JSON for a reference Image.
func TestMakeImageConfig(t *testing.T) {
for _, fixture := range fixtures {
v1Compatibility := loadFixtureFile(t, fixture+"/v1compatibility")
expectedConfig := loadFixtureFile(t, fixture+"/expected_config")
layerID := digest.Digest(loadFixtureFile(t, fixture+"/layer_id"))
parentID := digest.Digest(loadFixtureFile(t, fixture+"/parent_id"))
json, err := MakeImageConfig(v1Compatibility, layerID, parentID)
if err != nil {
t.Fatalf("MakeImageConfig on %s returned error: %v", fixture, err)
}
if !bytes.Equal(json, expectedConfig) {
t.Fatalf("did not get expected JSON for %s\nexpected: %s\ngot: %s", fixture, expectedConfig, json)
}
}
}
// TestGetStrongID makes sure that GetConfigJSON returns the expected
// hash for a reference Image.
func TestGetStrongID(t *testing.T) {
for _, fixture := range fixtures {
expectedConfig := loadFixtureFile(t, fixture+"/expected_config")
expectedComputedID := digest.Digest(loadFixtureFile(t, fixture+"/expected_computed_id"))
if id, err := StrongID(expectedConfig); err != nil || id != expectedComputedID {
t.Fatalf("did not get expected ID for %s\nexpected: %s\ngot: %s\nerror: %v", fixture, expectedComputedID, id, err)
}
}
}