From bebdd2bf7a446f4bead0b3f962c5204774a5c443 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Magiera?= <magik6k@gmail.com>
Date: Fri, 15 Dec 2017 20:55:31 +0100
Subject: [PATCH] config-patch: backup config
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

License: MIT
Signed-off-by: Łukasz Magiera <magik6k@gmail.com>
---
 core/commands/config.go       |  5 +++++
 repo/fsrepo/fsrepo.go         | 26 ++++++++++++++++++++++++++
 repo/mock.go                  |  4 ++++
 repo/repo.go                  |  1 +
 test/sharness/t0021-config.sh | 12 ++++++++++++
 5 files changed, 48 insertions(+)

diff --git a/core/commands/config.go b/core/commands/config.go
index 8736dd77f67b..24875c3ea1c8 100644
--- a/core/commands/config.go
+++ b/core/commands/config.go
@@ -372,6 +372,11 @@ func transformConfig(configRoot string, transformer config.Transformer) error {
 		return err
 	}
 
+	_, err = r.BackupConfig("profile-")
+	if err != nil {
+		return err
+	}
+
 	return r.SetConfig(cfg)
 }
 
diff --git a/repo/fsrepo/fsrepo.go b/repo/fsrepo/fsrepo.go
index 757c36438aeb..51823042a77e 100644
--- a/repo/fsrepo/fsrepo.go
+++ b/repo/fsrepo/fsrepo.go
@@ -480,6 +480,32 @@ func (r *FSRepo) FileManager() *filestore.FileManager {
 	return r.filemgr
 }
 
+func (r *FSRepo) BackupConfig(prefix string) (string, error) {
+	temp, err := ioutil.TempFile(r.path, "config-"+prefix)
+	if err != nil {
+		return "", err
+	}
+	defer temp.Close()
+
+	configFilename, err := config.Filename(r.path)
+	if err != nil {
+		return "", err
+	}
+
+	orig, err := os.OpenFile(configFilename, os.O_RDONLY, 0600)
+	if err != nil {
+		return "", err
+	}
+	defer orig.Close()
+
+	_, err = io.Copy(temp, orig)
+	if err != nil {
+		return "", err
+	}
+
+	return orig.Name(), nil
+}
+
 // setConfigUnsynced is for private use.
 func (r *FSRepo) setConfigUnsynced(updated *config.Config) error {
 	configFilename, err := config.Filename(r.path)
diff --git a/repo/mock.go b/repo/mock.go
index 030c2ff28d1a..3d05b8b7649f 100644
--- a/repo/mock.go
+++ b/repo/mock.go
@@ -28,6 +28,10 @@ func (m *Mock) SetConfig(updated *config.Config) error {
 	return nil
 }
 
+func (m *Mock) BackupConfig(prefix string) (string, error) {
+	return "config-" + prefix + "-backup", nil
+}
+
 func (m *Mock) SetConfigKey(key string, value interface{}) error {
 	return errTODO
 }
diff --git a/repo/repo.go b/repo/repo.go
index 0cbf8f536690..3403482c9ea8 100644
--- a/repo/repo.go
+++ b/repo/repo.go
@@ -18,6 +18,7 @@ var (
 
 type Repo interface {
 	Config() (*config.Config, error)
+	BackupConfig(prefix string) (string, error)
 	SetConfig(*config.Config) error
 
 	SetConfigKey(key string, value interface{}) error
diff --git a/test/sharness/t0021-config.sh b/test/sharness/t0021-config.sh
index a7ff59bcfcbb..9a086b1d8dd6 100755
--- a/test/sharness/t0021-config.sh
+++ b/test/sharness/t0021-config.sh
@@ -183,10 +183,18 @@ test_config_cmd() {
     test $(cat actual_config | wc -l) = 1
   '
 
+  test_expect_success "copy ipfs config" '
+    cp "$IPFS_PATH/config" before_patch
+  '
+
   test_expect_success "'ipfs config profile apply server' works" '
     ipfs config profile apply server
   '
 
+  test_expect_success "backup was created and looks good" '
+    test_cmp "$(find "$IPFS_PATH" -name "config-profile*")" before_patch
+  '
+
   test_expect_success "'ipfs config Swarm.AddrFilters' looks good with server profile" '
     ipfs config Swarm.AddrFilters > actual_config &&
     test $(cat actual_config | wc -l) = 17
@@ -209,6 +217,10 @@ test_config_cmd() {
   # won't work as it changes datastore definition, which makes ipfs not launch
   # without converting first
   # test_profile_apply_revert badgerds
+
+  test_expect_success "cleanup config backups" '
+    find "$IPFS_PATH" -name "config-profile*" -exec rm {} \;
+  '
 }
 
 test_init_ipfs