From 6d6b5bab3c42af563d96d9f49671f2c6a3483feb Mon Sep 17 00:00:00 2001
From: Niels de Vos <ndevos@redhat.com>
Date: Tue, 30 Jun 2020 08:43:24 +0200
Subject: [PATCH] rbd: add Unwrap() to error types

See-also: https://github.com/golang/go/wiki/ErrorValueFAQ#i-have-a-type-that-implements-error-and-holds-a-nested-error-how-should-i-adapt-it-to-the-new-features
Signed-off-by: Niels de Vos <ndevos@redhat.com>
---
 internal/rbd/errors.go | 30 ++++++++++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/internal/rbd/errors.go b/internal/rbd/errors.go
index a2d32bcd9..2675562ae 100644
--- a/internal/rbd/errors.go
+++ b/internal/rbd/errors.go
@@ -27,6 +27,11 @@ func (e ErrImageNotFound) Error() string {
 	return e.err.Error()
 }
 
+// Unwrap returns the encapsulated error of ErrImageNotFound.
+func (e ErrImageNotFound) Unwrap() error {
+	return e.err
+}
+
 // ErrSnapNotFound is returned when snap name passed is not found in the list of snapshots for the
 // given image
 type ErrSnapNotFound struct {
@@ -39,6 +44,11 @@ func (e ErrSnapNotFound) Error() string {
 	return e.err.Error()
 }
 
+// Unwrap returns the encapsulated error of ErrSnapNotFound.
+func (e ErrSnapNotFound) Unwrap() error {
+	return e.err
+}
+
 // ErrVolNameConflict is generated when a requested CSI volume name already exists on RBD but with
 // different properties, and hence is in conflict with the passed in CSI volume name
 type ErrVolNameConflict struct {
@@ -51,6 +61,11 @@ func (e ErrVolNameConflict) Error() string {
 	return e.err.Error()
 }
 
+// Unwrap returns the encapsulated error of ErrVolNameConflict.
+func (e ErrVolNameConflict) Unwrap() error {
+	return e.err
+}
+
 // ErrInvalidVolID is returned when a CSI passed VolumeID does not conform to any known volume ID
 // formats
 type ErrInvalidVolID struct {
@@ -62,6 +77,11 @@ func (e ErrInvalidVolID) Error() string {
 	return e.err.Error()
 }
 
+// Unwrap returns the encapsulated error of ErrInvalidVolID.
+func (e ErrInvalidVolID) Unwrap() error {
+	return e.err
+}
+
 // ErrMissingStash is returned when the image metadata stash file is not found
 type ErrMissingStash struct {
 	err error
@@ -72,6 +92,11 @@ func (e ErrMissingStash) Error() string {
 	return e.err.Error()
 }
 
+// Unwrap returns the encapsulated error of ErrMissingStash.
+func (e ErrMissingStash) Unwrap() error {
+	return e.err
+}
+
 // ErrFlattenInProgress is returned when flatten is inprogess for an image
 type ErrFlattenInProgress struct {
 	err error
@@ -81,3 +106,8 @@ type ErrFlattenInProgress struct {
 func (e ErrFlattenInProgress) Error() string {
 	return e.err.Error()
 }
+
+// Unwrap returns the encapsulated error of ErrFlattenInProgress.
+func (e ErrFlattenInProgress) Unwrap() error {
+	return e.err
+}