🐛 Load overlay config from cos-layout.env (#71)

Load the base overlay config from the cos-layout.env file. This means we
have to depend the base overlay mount to the load-config step, which
moves things a bit in the DAG.

Signed-off-by: Itxaka <itxaka.garcia@spectrocloud.com>

earthly.sh

@@ -1,3 +1,3 @@
 #!/bin/bash
 
-docker run --privileged -v /var/run/docker.sock:/var/run/docker.sock --rm -t -v $(pwd):/workspace -v earthly-tmp:/tmp/earthly:rw earthly/earthly:v0.6.30 --allow-privileged $@
+docker run --privileged -v /var/run/docker.sock:/var/run/docker.sock --rm -t -v $(pwd):/workspace -v earthly-tmp:/tmp/earthly:rw earthly/earthly:v0.7.1 --allow-privileged $@

internal/utils/mounts.go

@@ -199,6 +199,7 @@ func GetOemTimeout() int {
 
 // GetOverlayBase parses the cdmline and gets the overlay config
 // Format is rd.cos.overlay=tmpfs:20% or rd.cos.overlay=LABEL=$LABEL or rd.cos.overlay=UUID=$UUID
+// Notice that this can be later override by the config coming from cos-layout.env
 func GetOverlayBase() string {
 	overlayConfig := ReadCMDLineArg("rd.cos.overlay=")
 	if len(overlayConfig) == 0 {

pkg/mount/dag_steps.go

@@ -140,6 +140,12 @@ func (s *State) LoadEnvLayoutDagStep(g *herd.Graph, deps ...string) error {
 			// Remove any duplicates
 			s.BindMounts = internalUtils.UniqueSlice(internalUtils.CleanupSlice(s.BindMounts))
 
+			// Load Overlay config
+			overlayConfig := env["OVERLAY"]
+			if overlayConfig != "" {
+				s.OverlayBase = overlayConfig
+			}
+
 			s.StateDir = env["PERSISTENT_STATE_TARGET"]
 			if s.StateDir == "" {
 				s.StateDir = cnst.PersistentStateTarget
@@ -190,8 +196,10 @@ func (s *State) MountOemDagStep(g *herd.Graph, deps ...string) error {
 }
 
 // MountBaseOverlayDagStep will add mounting /run/overlay as an overlay dir
+// Requires the config-load step because some parameters can come from there
 func (s *State) MountBaseOverlayDagStep(g *herd.Graph) error {
 	return g.Add(cnst.OpMountBaseOverlay,
+		herd.WithDeps(cnst.OpLoadConfig),
 		herd.WithCallback(
 			func(ctx context.Context) error {
 				op, err := baseOverlay(Overlay{
@@ -221,7 +229,7 @@ func (s *State) MountBaseOverlayDagStep(g *herd.Graph) error {
 // MountCustomOverlayDagStep will add mounting s.OverlayDirs under /run/overlay
 func (s *State) MountCustomOverlayDagStep(g *herd.Graph) error {
 	return g.Add(cnst.OpOverlayMount,
-		herd.WithDeps(cnst.OpLoadConfig),
+		herd.WithDeps(cnst.OpLoadConfig, cnst.OpMountBaseOverlay),
 		herd.WithCallback(
 			func(ctx context.Context) error {
 				var multierr *multierror.Error

pkg/mount/state_test.go

@@ -78,48 +78,40 @@ func checkLiveCDDag(dag [][]herd.GraphEntry, actualDag string) {
 func checkDag(dag [][]herd.GraphEntry, actualDag string) {
 	Expect(len(dag)).To(Equal(10), actualDag)
 	Expect(len(dag[0])).To(Equal(1), actualDag)
-	Expect(len(dag[1])).To(Equal(4), actualDag)
+	Expect(len(dag[1])).To(Equal(3), actualDag)
 	Expect(len(dag[2])).To(Equal(1), actualDag)
 	Expect(len(dag[3])).To(Equal(1), actualDag)
 	Expect(len(dag[4])).To(Equal(1), actualDag)
 	Expect(len(dag[5])).To(Equal(1), actualDag)
 	Expect(len(dag[6])).To(Equal(1), actualDag)
 	Expect(len(dag[7])).To(Equal(2), actualDag)
-	Expect(len(dag[8])).To(Equal(1), actualDag)
+	Expect(len(dag[8])).To(Equal(2), actualDag)
 	Expect(len(dag[9])).To(Equal(1), actualDag)
 
 	Expect(dag[0][0].Name).To(Equal("init"))
 	Expect(dag[1][0].Name).To(Or(
 		Equal("mount-tmpfs"),
 		Equal("create-sentinel"),
-		Equal("mount-base-overlay"),
 		Equal("mount-state"),
 	), actualDag)
 	Expect(dag[1][1].Name).To(Or(
 		Equal("mount-tmpfs"),
 		Equal("create-sentinel"),
-		Equal("mount-base-overlay"),
 		Equal("mount-state"),
 	), actualDag)
 	Expect(dag[1][2].Name).To(Or(
 		Equal("mount-tmpfs"),
 		Equal("create-sentinel"),
-		Equal("mount-base-overlay"),
-		Equal("mount-state"),
-	), actualDag)
-	Expect(dag[1][3].Name).To(Or(
-		Equal("mount-tmpfs"),
-		Equal("create-sentinel"),
-		Equal("mount-base-overlay"),
 		Equal("mount-state"),
 	), actualDag)
 	Expect(dag[2][0].Name).To(Equal("discover-state"), actualDag)
 	Expect(dag[3][0].Name).To(Equal("mount-root"), actualDag)
 	Expect(dag[4][0].Name).To(Equal("mount-oem"), actualDag)
 	Expect(dag[5][0].Name).To(Equal("rootfs-hook"), actualDag)
 	Expect(dag[6][0].Name).To(Equal("load-config"), actualDag)
-	Expect(dag[7][0].Name).To(Or(Equal("overlay-mount"), Equal("custom-mount")), actualDag)
-	Expect(dag[7][1].Name).To(Or(Equal("overlay-mount"), Equal("custom-mount")), actualDag)
-	Expect(dag[8][0].Name).To(Equal("mount-bind"), actualDag)
+	Expect(dag[7][0].Name).To(Or(Equal("mount-base-overlay"), Equal("custom-mount")), actualDag)
+	Expect(dag[7][1].Name).To(Or(Equal("mount-base-overlay"), Equal("custom-mount")), actualDag)
+	Expect(dag[8][0].Name).To(Or(Equal("mount-bind"), Equal("overlay-mount")), actualDag)
+	Expect(dag[8][1].Name).To(Or(Equal("mount-bind"), Equal("overlay-mount")), actualDag)
 	Expect(dag[9][0].Name).To(Equal("write-fstab"), actualDag)
 }