mbsecli

Website & Live Demo: https://techmuch.github.io/mbseCLI/

A CLI + local web server for live visualization and review of SysML v2 textual models. Point it at a .sysml file (or a directory of them) and it watches the file, parses it, and serves an interactive UI — object tree, dockable diagram views, element inspector — that updates as the model changes on disk.

Same shape as mbseCLI's sibling tools: a single Go binary with an embedded React frontend, no separate server process or install step for end users.

Status

Early scaffold. The parser is a deliberately naive, line-oriented tokenizer covering common declaration forms (package, part def, part, port, action, state, requirement, attribute) — enough to drive the tree, diagram, and live-reload pipeline end to end. It is not a conformant SysML v2 / KerML parser. See internal/parser/parser.go for the intended seam to swap in a generated ANTLR4 parser later.

Quick start

make build
./mbsecli start --open examples/drone.sysml

Then edit examples/drone.sysml in your editor and watch the tree and diagram update.

Development

# Terminal 1: Go server in --dev mode (serves /api and /ws only)
make dev

# Terminal 2: Vite dev server with hot reload, proxying /api and /ws to :4173
cd web && npm run dev

Open http://localhost:5173 during development.

Architecture

.sysml file on disk
  -> internal/watch   (fsnotify, debounced)
  -> internal/parser  (naive tokenizer -> internal/model.Graph)
  -> internal/server  (WebSocket broadcast + REST API)
  -> web/ (React + nexus-shell)
       left pane:   object tree (TreeWidget)
       center pane: dockable diagram views (GraphCanvas, registered per view type)
       right pane:  element inspector + feedback notes (PropertyPanel + custom notes UI)

Feedback notes are anchored to an element's fully-qualified name (FQN) and persisted to a JSON sidecar file next to the model (.<model_name>.feedback.json) — plain text, diffable, travels with the model in version control. Notes whose FQN no longer exists after a reparse (element renamed/deleted) are flagged as orphaned rather than dropped.

Testing

make test    # Go unit tests: internal/parser, internal/feedback
make e2e     # Playwright, against a real running mbsecli instance

The e2e suite (web/e2e/) boots mbsecli against a scratch copy of examples/drone.sysml (see web/e2e/start-server.sh) so it's free to edit the file on disk — that's what the live-reload test exercises. First-time setup needs the browser binary once:

cd web && npx playwright install chromium

CLI

mbsecli start [file-or-directory]   # default: current directory
  --port 4173        # web UI / API port
  --debounce 200ms    # file-change debounce window
  --open, -o          # open browser automatically once started
  --dev               # skip embedded assets; pair with `npm run dev`
mbsecli version

Next steps

• Swap the naive parser for a generated ANTLR4 parser from the OMG SysML.g4 / KerML.g4 grammars (antlr4 -Dlanguage=Go), preserving internal/model.Graph as the output shape.
• Additional view types on the same Graph IR: interconnection/IBD (ports + connect), behavioral (action/state flow), requirement traceability (satisfy/verify matrix).
• "Export notes to model" — write resolved feedback back into the .sysml source as doc /* ... */ annotations.