PR Summary: Singularity Container Service Support

Overview

Adds Singularity/Apptainer container service support to the edge client, enabling runs on systems without Docker. The central client remains Docker-only.

Changes

Edge Client (edgeFederatedClient)

• src/runCoordinator/nodeManager/launchNode.ts
  • Added launchSingularityNode() and attachSingularityEventHandlers()
  • Detects singularity or apptainer binary
  • Finds .sif image files in configured directories
  • Handles bind mounts, environment variables, and process management
  • Propagates container exit codes to callbacks

Central Client (centralFederatedClient)

• src/runCoordinator/nodeManager/launchNode.ts
  • Enforced Docker-only; throws error if non-Docker service requested

Configuration

• Added containerService?: string to edge client config (defaults to 'docker')
• Updated all Electron app config files with containerService: "docker"

Image Management

• desktopApp/electronApp/src/singularityImageManager.ts (new)
  • Pulls and converts Docker images to Singularity format
  • Uses network API to get Docker image digests (no Docker required)
  • Hash-based naming: {image_name}-{hash}.sif
  • Stores images in {pathBaseDirectory}/singularityImages/
  • Auto-cleans old image versions

UI Updates

• Consortium Page: Hides Docker command section when using Singularity
• Terminal Window: Shows "Run Singularity Pull" button, streams pull output in real-time
• Added IPC handlers and React API methods for Singularity operations

Error Handling

• Fixed container exit error reporting to match Docker pattern
• Updated error callbacks to include actual error messages
• Properly captures stdout/stderr for error reporting

Technical Details

• Images stored in: {pathBaseDirectory}/singularityImages/
• Uses Docker Registry API v2 for digest retrieval (works without Docker)
• Container execution: singularity run --containall --writable-tmpfs -e
• Host networking (default for Singularity)

Breaking Changes

None. All changes are backward compatible. Docker remains the default.