Sort bind mounts (#134)

* Sort bind mounts

Signed-off-by: Mauro Morales <mauro.morales@spectrocloud.com>

* Add comment

Signed-off-by: Mauro Morales <mauro.morales@spectrocloud.com>

---------

Signed-off-by: Mauro Morales <mauro.morales@spectrocloud.com>

pkg/mount/dag_steps.go

@@ -308,7 +308,7 @@ func (s *State) MountCustomBindsDagStep(g *herd.Graph) error {
 				var err *multierror.Error
 				internalUtils.Log.Debug().Strs("mounts", s.BindMounts).Msg("Mounting binds")
 
-				for _, p := range s.BindMounts {
+				for _, p := range s.SortedBindMounts() {
 					internalUtils.Log.Debug().Str("what", p).Msg("Bind mount start")
 					op := mountBind(p, s.Rootdir, s.StateDir)
 					err2 := op.run()

pkg/mount/state.go

@@ -6,6 +6,8 @@ import (
 	"fmt"
 	"os"
 	"path/filepath"
+	"sort"
+	"strings"
 	"time"
 
 	"github.com/containerd/containerd/mount"
@@ -31,6 +33,22 @@ type State struct {
 	fstabs       []*fstab.Mount
 }
 
+// SortedBindMounts returns the nodes with less depth first and in alphabetical order.
+func (s *State) SortedBindMounts() []string {
+	bindMountsCopy := s.BindMounts
+	sort.Slice(bindMountsCopy, func(i, j int) bool {
+		iAry := strings.Split(bindMountsCopy[i], "/")
+		jAry := strings.Split(bindMountsCopy[j], "/")
+		iSize := len(iAry)
+		jSize := len(jAry)
+		if iSize == jSize {
+			return strings.Compare(iAry[len(iAry)-1], jAry[len(jAry)-1]) == -1
+		}
+		return iSize < jSize
+	})
+	return bindMountsCopy
+}
+
 func (s *State) path(p ...string) string {
 	return filepath.Join(append([]string{s.Rootdir}, p...)...)
 }

pkg/mount/state_test.go

@@ -19,6 +19,27 @@ var _ = Describe("mounting immutable setup", func() {
 		Expect(g).ToNot(BeNil())
 	})
 
+	Context("SortedBindMounts()", func() {
+		It("returns the nodes with less depth first and in alfabetical order", func() {
+			s := &mount.State{
+				BindMounts: []string{
+					"/etc/nginx/config.d/",
+					"/etc/nginx",
+					"/etc/kubernetes/child",
+					"/etc/kubernetes",
+					"/etc/kubernetes/child/grand-child",
+				},
+			}
+			Expect(s.SortedBindMounts()).To(Equal([]string{
+				"/etc/kubernetes",
+				"/etc/nginx",
+				"/etc/kubernetes/child",
+				"/etc/nginx/config.d/",
+				"/etc/kubernetes/child/grand-child",
+			}))
+		})
+	})
+
 	Context("simple invocation", func() {
 		It("generates normal dag", func() {
 			Skip("Cant override bootstate yet")