delegation: add a Bundle to carry around decoded, sealed and Cid

token/delegation/utilities.go

@@ -0,0 +1,24 @@
+package delegation
+
+import (
+	"fmt"
+
+	"github.com/ipfs/go-cid"
+)
+
+// ErrDelegationNotFound is returned if a delegation token is not found
+var ErrDelegationNotFound = fmt.Errorf("delegation not found")
+
+// Loader is a delegation token loader.
+type Loader interface {
+	// GetDelegation returns the delegation.Token matching the given CID.
+	// If not found, ErrDelegationNotFound is returned.
+	GetDelegation(cid cid.Cid) (*Token, error)
+}
+
+// Bundle carries together a decoded delegation with its Cid and raw signed data.
+type Bundle struct {
+	Cid     cid.Cid
+	Decoded *Token
+	Sealed  []byte
+}