start

client/plan.go

@@ -25,6 +25,11 @@ type AddLayerOptions struct {
 	// has the given label. False (the default) means append a new layer.
 	Combine bool
 
+	// Inner true means a new layer append may go into an existing
+	// subdirectory, even through it may not result in appending it
+	// to the end of the layers slice (it becomes an insert).
+	Inner bool
+
 	// Label is the label for the new layer if appending, and the label of the
 	// layer to combine with if Combine is true.
 	Label string
@@ -38,12 +43,14 @@ func (client *Client) AddLayer(opts *AddLayerOptions) error {
 	var payload = struct {
 		Action  string `json:"action"`
 		Combine bool   `json:"combine"`
+		Inner   bool   `json:"inner"`
 		Label   string `json:"label"`
 		Format  string `json:"format"`
 		Layer   string `json:"layer"`
 	}{
 		Action:  "add",
 		Combine: opts.Combine,
+		Inner:   opts.Inner,
 		Label:   opts.Label,
 		Format:  "yaml",
 		Layer:   string(opts.LayerData),

internals/cli/cmd_add.go

@@ -35,6 +35,7 @@ type cmdAdd struct {
 	client *client.Client
 
 	Combine    bool `long:"combine"`
+	Inner    bool `long:"inner"`
 	Positional struct {
 		Label     string `positional-arg-name:"<label>" required:"1"`
 		LayerPath string `positional-arg-name:"<layer-path>" required:"1"`
@@ -48,6 +49,7 @@ func init() {
 		Description: cmdAddDescription,
 		ArgsHelp: map[string]string{
 			"--combine": "Combine the new layer with an existing layer that has the given label (default is to append)",
+			"--inner": "Allow appending a new layer inside an existing subdirectory",
 		},
 		New: func(opts *CmdOptions) flags.Commander {
 			return &cmdAdd{client: opts.Client}
@@ -65,6 +67,7 @@ func (cmd *cmdAdd) Execute(args []string) error {
 	}
 	opts := client.AddLayerOptions{
 		Combine:   cmd.Combine,
+		Inner:     cmd.Inner,
 		Label:     cmd.Positional.Label,
 		LayerData: data,
 	}

internals/daemon/api_plan.go

@@ -43,6 +43,7 @@ func v1PostLayers(c *Command, r *http.Request, _ *UserState) Response {
 	var payload struct {
 		Action  string `json:"action"`
 		Combine bool   `json:"combine"`
+		Inner    bool  `json:"inner"`
 		Label   string `json:"label"`
 		Format  string `json:"format"`
 		Layer   string `json:"layer"`

internals/plan/plan.go

@@ -1227,6 +1227,14 @@ func (p *Plan) checkCycles() error {
 	return err
 }
 
+// labelExp represents a match of a valid layer label, which may include a
+// directory prefix (which excludes the '.d' ending).
+//
+// Examples:
+// foo
+// bar/baz
+var labelExp = regexp.MustCompile("^(([a-z](?:-?[a-z0-9]){2,})/)?([a-z](?:-?[a-z0-9]){2,})$")
+
 func ParseLayer(order int, label string, data []byte) (*Layer, error) {
 	layer := &Layer{
 		Services:   make(map[string]*Service),
@@ -1349,7 +1357,14 @@ func validServiceAction(action ServiceAction, additionalValid ...ServiceAction)
 	}
 }
 
-var fnameExp = regexp.MustCompile("^([0-9]{3})-([a-z](?:-?[a-z0-9]){2,}).yaml$")
+// fnameExp represents a match of a valid layer path, which typically
+// consists of only the file name. Optionally, it include a single level
+// subdirectory prefix which ends with '.d'.
+//
+// Examples:
+// 001-abc.yaml           => ["001-abc.yaml", "", "", "", "001", "abc"]
+// 002-foo.d/001-bar.yaml => ["002-foo.d/001-bar.yaml", "002-foo.d/", "002", "foo", "001", "bar"]
+var fnameExp = regexp.MustCompile("^(([0-9]{3})-([a-z](?:-?[a-z0-9]){2,})\.d/)?([0-9]{3})-([a-z](?:-?[a-z0-9]){2,}).yaml$")
 
 func ReadLayersDir(dirname string) ([]*Layer, error) {
 	finfos, err := os.ReadDir(dirname)
@@ -1381,8 +1396,15 @@ func ReadLayersDir(dirname string) ([]*Layer, error) {
 			// Errors from package os generally include the path.
 			return nil, fmt.Errorf("cannot read layer file: %v", err)
 		}
-		label := match[2]
-		order, err := strconv.Atoi(match[1])
+
+		label = match[5]
+		orderStr = match[4]
+		if match[1] != "" {
+			// We have a subdirectory
+			label = match[3] + "/" + label
+			orderStr = match[2] + orderStr
+		}
+		order, err := strconv.Atoi(orderStr)
 		if err != nil {
 			panic(fmt.Sprintf("internal error: filename regexp is wrong: %v", err))
 		}