buildkit/cache/remotecache/local/local.go

84 lines
2.5 KiB
Go

package local
import (
"context"
"time"
"github.com/containerd/containerd/content"
"github.com/moby/buildkit/cache/remotecache"
"github.com/moby/buildkit/session"
sessioncontent "github.com/moby/buildkit/session/content"
digest "github.com/opencontainers/go-digest"
specs "github.com/opencontainers/image-spec/specs-go/v1"
"github.com/pkg/errors"
)
const (
attrDigest = "digest"
attrSrc = "src"
attrDest = "dest"
contentStoreIDPrefix = "local:"
)
// ResolveCacheExporterFunc for "local" cache exporter.
func ResolveCacheExporterFunc(sm *session.Manager) remotecache.ResolveCacheExporterFunc {
return func(ctx context.Context, attrs map[string]string) (remotecache.Exporter, error) {
store := attrs[attrDest]
if store == "" {
return nil, errors.New("local cache exporter requires dest")
}
csID := contentStoreIDPrefix + store
cs, err := getContentStore(ctx, sm, csID)
if err != nil {
return nil, err
}
return remotecache.NewExporter(cs), nil
}
}
// ResolveCacheImporterFunc for "local" cache importer.
func ResolveCacheImporterFunc(sm *session.Manager) remotecache.ResolveCacheImporterFunc {
return func(ctx context.Context, attrs map[string]string) (remotecache.Importer, specs.Descriptor, error) {
dgstStr := attrs[attrDigest]
if dgstStr == "" {
return nil, specs.Descriptor{}, errors.New("local cache importer requires explicit digest")
}
dgst := digest.Digest(dgstStr)
store := attrs[attrSrc]
if store == "" {
return nil, specs.Descriptor{}, errors.New("local cache importer requires src")
}
csID := contentStoreIDPrefix + store
cs, err := getContentStore(ctx, sm, csID)
if err != nil {
return nil, specs.Descriptor{}, err
}
info, err := cs.Info(ctx, dgst)
if err != nil {
return nil, specs.Descriptor{}, err
}
desc := specs.Descriptor{
// MediaType is typically MediaTypeDockerSchema2ManifestList,
// but we leave it empty until we get correct support for local index.json
Digest: dgst,
Size: info.Size,
}
return remotecache.NewImporter(cs), desc, nil
}
}
func getContentStore(ctx context.Context, sm *session.Manager, storeID string) (content.Store, error) {
sessionID := session.FromContext(ctx)
if sessionID == "" {
return nil, errors.New("local cache exporter/importer requires session")
}
timeoutCtx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
defer cancel()
caller, err := sm.Get(timeoutCtx, sessionID)
if err != nil {
return nil, err
}
return sessioncontent.NewCallerStore(caller, storeID), nil
}