EMF WebApp

A modern, web-based alternative to the Eclipse Modeling Framework (EMF). Design Ecore metamodels visually, validate with OCL, generate code, and export Eclipse-compatible .ecore files — all from your browser.

Live demo: emf-webapp.fly.dev

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Features

• Visual Metamodel Editor — Drag-and-drop diagram editor (React Flow) for EClasses, EAttributes, EReferences, EEnums, and inheritance
• Eclipse Interoperability — Import/export .ecore XMI files fully compatible with Eclipse EMF (v2.45.0)
• OCL Constraints — Define and validate Object Constraint Language rules against model instances
• Code Generation — Template-based code generation from metamodels (Java, TypeScript, etc.)
• M1 Model Instances — Create and manage instances conforming to your metamodels
• DeepLink Navigation — Click any EClass/M1 model node to jump directly to its property inspector
• Auto-Layout — Dagre-based hierarchical layout (top-bottom / left-right) with fit-to-view
• Onboarding Tour — Guided first-use walkthrough with auto-dismiss on click-outside
• Toast Notifications — Real-time success/error feedback for all CRUD operations
• GenModel Export — Generate .genmodel files for Eclipse code generation workflows
• Project Management — Organize metamodels, models, and constraints within projects

Architecture

emf-webapp/
├── packages/
│   ├── core/        # Ecore model, XMI serialization, OCL engine (shared)
│   ├── backend/     # NestJS REST API + SQLite persistence
│   └── frontend/    # React 19 + Vite + React Flow diagram editor
├── .github/workflows/
│   └── deploy.yml   # GitHub Actions → Fly.io (auto-deploy on push to main)
├── fly.toml         # Fly.io deployment config
└── Dockerfile       # Production multi-stage build

Layer	Stack
Frontend	React 19, Vite, React Flow, Monaco Editor, Tailwind CSS 4, shadcn/ui
Backend	NestJS, TypeORM, SQLite
Core	TypeScript (shared serialization + OCL)
Deploy	Fly.io (auto-scale to zero, persistent volume emfdata)
CI/CD	GitHub Actions (automated deploy on push to main)

Getting Started

Prerequisites

• Node.js ≥ 20
• npm ≥ 10

Install & Run

# Clone
git clone https://github.com/ivanrclaw/emf-webapp.git
cd emf-webapp

# Install dependencies
npm install

# Build core (required first)
npm run build -w packages/core

# Development (backend + frontend)
npm run dev

The frontend runs on http://localhost:5173 and the backend API on http://localhost:3000.

Run Tests

npm run test

Currently 184 tests across core (160) and backend (24).

Eclipse Interoperability

EMF WebApp produces .ecore files that are directly importable into Eclipse:

• Correct XMI namespace declarations (xmi:version="2.0", xmlns:ecore)
• Proper eType references (#//ClassName, ecore:EDataType http://...)
• eSuperTypes for inheritance chains
• Default value omission (matches Eclipse behavior)
• xmi:id only on classifiers (EClass, EEnum, EDataType)
• GenModel generation with all genClasses and genEnums
• Error-safe export: robust try/catch on all XMI serialization paths

Import from Eclipse

curl -X POST https://emf-webapp.fly.dev/api/projects/{pid}/xmi/{mmid}/import \
  -H 'Content-Type: application/json' \
  -d '{"xml": "<your .ecore XML content>"}'

Export to Eclipse

curl https://emf-webapp.fly.dev/api/projects/{pid}/xmi/{mmid}/ecore

API Overview

Method	Endpoint	Description
GET/POST	/api/projects	List/create projects
GET/POST	/api/projects/:pid/metamodels	List/create metamodels
POST	/api/projects/:pid/xmi/:mmid/import	Import .ecore XMI
GET	/api/projects/:pid/xmi/:mmid/ecore	Export .ecore XMI
GET	/api/projects/:pid/xmi/:mmid/genmodel	Export .genmodel
GET/POST	/api/metamodels/:mmid/constraints	OCL constraints CRUD
POST	/api/metamodels/:mmid/constraints/validate	Validate OCL against model
GET/POST	/api/projects/:pid/metamodels/:mmid/models	M1 model instances CRUD
GET/POST	/api/metamodels/:mmid/templates	Code generation templates

Deployment

Deployed on Fly.io with auto-scaling:

fly deploy

Configuration in fly.toml — uses a persistent volume (emfdata) for SQLite data.

Automated deployment

Push to main triggers an automatic deploy via GitHub Actions (requires FLY_API_TOKEN secret configured in repo settings).

License

MIT

Author

Iván Ruiz López — UNEX (Universidad de Extremadura)