Add kpod diff command

kpod diff reports on differences between two layers, specified as
layer IDs, containers, or images.  In the case of containers or
images, kpod diff produces a diff for the top layer

Signed-off-by: Ryan Cole <rcyoalne@gmail.com>
This commit is contained in:
Ryan Cole 2017-08-01 16:47:12 -04:00
parent fb2ee59225
commit 949268f958
6 changed files with 238 additions and 0 deletions

54
libkpod/diff.go Normal file
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package libkpod
import (
"github.com/containers/storage/pkg/archive"
"github.com/kubernetes-incubator/cri-o/libkpod/image"
"github.com/kubernetes-incubator/cri-o/libkpod/layer"
"github.com/pkg/errors"
)
// GetDiff returns the differences betwen the two images, layers, or containers
func (c *ContainerServer) GetDiff(from, to string) ([]archive.Change, error) {
toLayer, err := c.getLayerID(to)
if err != nil {
return nil, err
}
fromLayer := ""
if from != "" {
fromLayer, err = c.getLayerID(from)
if err != nil {
return nil, err
}
}
return c.Store().Changes(fromLayer, toLayer)
}
// GetLayerID gets a full layer id given a full or partial id
// If the id matches a container or image, the id of the top layer is returned
// If the id matches a layer, the top layer id is returned
func (c *ContainerServer) getLayerID(id string) (string, error) {
var toLayer string
toImage, err := image.FindImage(c.store, id)
if err != nil {
toCtr, err := c.store.Container(id)
if err != nil {
toLayer, err = layer.FullID(c.store, id)
if err != nil {
return "", errors.Errorf("layer, image, or container %s does not exist", id)
}
} else {
toLayer = toCtr.LayerID
}
} else {
toLayer = toImage.TopLayer
}
return toLayer, nil
}
func (c *ContainerServer) getLayerParent(layerID string) (string, error) {
layer, err := c.store.Layer(layerID)
if err != nil {
return "", err
}
return layer.Parent, nil
}

12
libkpod/layer/layer.go Normal file
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package layer
import cstorage "github.com/containers/storage"
// FullID gets the full id of a layer given a partial id or name
func FullID(store cstorage.Store, id string) (string, error) {
layer, err := store.Layer(id)
if err != nil {
return "", err
}
return layer.ID, nil
}