Add support for opening subfolders in VS Code devcontainer commands

Author: stuartleeks

cmd/devcontainerx/openincode.go

@@ -3,45 +3,78 @@ package main
 import (
 	"fmt"
 	"os/exec"
+	"path/filepath"
+	"strings"
 
 	"github.com/spf13/cobra"
 	"github.com/stuartleeks/devcontainer-cli/internal/pkg/devcontainers"
 	"github.com/stuartleeks/devcontainer-cli/internal/pkg/wsl"
 )
 
 func createOpenInCodeCommand() *cobra.Command {
+	var subFolder string
 	cmd := &cobra.Command{
 		Use:   "open-in-code <path>",
 		Short: "open the specified path devcontainer project in VS Code",
 		Long:  "Open the specified path (containing a .devcontainer folder in VS Code",
 		RunE: func(cmd *cobra.Command, args []string) error {
-			return launchDevContainer(cmd, "code", args)
+			return launchDevContainer(cmd, "code", args, subFolder)
 		},
 	}
+	cmd.Flags().StringVarP(&subFolder, "sub-folder", "s", "", "sub-folder within the devcontainer to open")
 	return cmd
 }
 func createOpenInCodeInsidersCommand() *cobra.Command {
+	var subFolder string
 	cmd := &cobra.Command{
 		Use:   "open-in-code-insiders <path>",
 		Short: "open the specified path devcontainer project in VS Code Insiders",
 		Long:  "Open the specified path (containing a .devcontainer folder in VS Code Insiders",
 		RunE: func(cmd *cobra.Command, args []string) error {
-			return launchDevContainer(cmd, "code-insiders", args)
+			return launchDevContainer(cmd, "code-insiders", args, subFolder)
 		},
 	}
+	cmd.Flags().StringVarP(&subFolder, "sub-folder", "s", "", "sub-folder within the devcontainer to open")
 	return cmd
 }
 
-func launchDevContainer(cmd *cobra.Command, appBase string, args []string) error {
+func launchDevContainer(cmd *cobra.Command, appBase string, args []string, subFolder string) error {
 	if len(args) > 1 {
 		return cmd.Usage()
 	}
 	path := "." // default to current directory
-	if len(args) == 1 {
+	if len(args) >= 1 {
 		path = args[0]
 	}
 
-	launchURI, err := devcontainers.GetDevContainerURI(path)
+	// allow the command to be invoked from a subfolder of the folder containing the devcontainer.json by searching ancestor paths for a devcontainer.json
+	devcontainerPath, err := devcontainers.FindDevContainerInAncestorPaths(path)
+	if err != nil {
+		return fmt.Errorf("error finding devcontainer.json: %s", err)
+	}
+	fmt.Printf("Found devcontainer.json at %s\n", devcontainerPath)
+
+	// If subFolder is not empty then use that as the path to open in VS Code (note it should be relative to the folder containing the devcontainer.json/.devcontainer folder)
+	// If subFolder is empty and the current folder is contained within the folder containing the devcontainer.json, then open the current folder in VS Code, otherwise open the folder containing the devcontainer.json in VS Code
+	if subFolder == "" {
+		absDevContainerPath, err := filepath.Abs(devcontainerPath)
+		if err != nil {
+			return fmt.Errorf("error getting absolute path: %s", err)
+		}
+		absCurrentPath, err := filepath.Abs(path)
+		if err != nil {
+			return fmt.Errorf("error getting absolute path: %s", err)
+		}
+		if absCurrentPath != absDevContainerPath && strings.HasPrefix(absCurrentPath, absDevContainerPath) {
+			subFolder, err = filepath.Rel(absDevContainerPath, absCurrentPath)
+			if err != nil {
+				return fmt.Errorf("error getting relative path: %s", err)
+			}
+			fmt.Printf("Opening subfolder %s within devcontainer\n", subFolder)
+		}
+	}
+
+	launchURI, err := devcontainers.GetDevContainerURI(devcontainerPath, subFolder)
 	if err != nil {
 		return err
 	}

internal/pkg/devcontainers/devcontainer.go

@@ -20,3 +20,38 @@ func getDevContainerJsonPath(folderPath string) (string, error) {
 
 	return "", fmt.Errorf("devcontainer.json not found. Looked for %s", strings.Join(pathsToTest, ","))
 }
+
+func FindDevContainerInAncestorPaths(folderPath string) (string, error) {
+	currentPath, err := filepath.Abs(folderPath)
+	if err != nil {
+		return "", fmt.Errorf("error getting absolute path: %w", err)
+	}
+
+	for {
+		// Check if devcontainer.json exists in current path
+		_, err := getDevContainerJsonPath(currentPath)
+		if err == nil {
+			return currentPath, nil
+		}
+
+		// Check if this is a git repository root
+		gitPath := filepath.Join(currentPath, ".git")
+		gitInfo, gitErr := os.Stat(gitPath)
+		isGitRoot := gitErr == nil && gitInfo.IsDir()
+
+		// If we're at a git root, stop searching (we already checked this folder)
+		if isGitRoot {
+			return "", fmt.Errorf("devcontainer.json not found in ancestor paths")
+		}
+
+		// Move to parent directory
+		parentPath := filepath.Dir(currentPath)
+
+		// Check if we've reached the root (parent is same as current)
+		if parentPath == currentPath {
+			return "", fmt.Errorf("devcontainer.json not found in ancestor paths")
+		}
+
+		currentPath = parentPath
+	}
+}

internal/pkg/devcontainers/remoteuri.go

@@ -12,7 +12,8 @@ import (
 )
 
 // GetDevContainerURI gets the devcontainer URI for a folder to launch using the VS Code --folder-uri switch
-func GetDevContainerURI(folderPath string) (string, error) {
+// If subFolder is specified, it is appended to the workspaceMountPath
+func GetDevContainerURI(folderPath string, subFolder string) (string, error) {
 
 	absPath, err := filepath.Abs(folderPath)
 	if err != nil {
@@ -33,6 +34,9 @@ func GetDevContainerURI(folderPath string) (string, error) {
 	if err != nil {
 		return "", err
 	}
+	if subFolder != "" {
+		workspaceMountPath = filepath.Join(workspaceMountPath, subFolder)
+	}
 	uri := fmt.Sprintf("vscode-remote://dev-container+%s%s", launchPathHex, workspaceMountPath)
 
 	return uri, nil