Semantta

A web‑based, RDF‑native platform for managing linked data based on OWL/RDF ontologies.

Architecture

Semantta is built around a three‑layer architecture:

1. Ontology Layer: Provides capability to import semantics that represent knowledge about a domain, including concepts in the domian and relationships among them.
2. Application Profile (AP) Layer: Provides capability to tailor the semantics from the Ontology Layer to the needs of a specific application.
3. Metadata Layer: Provides capability to apply the tailored semantics from the AP Layer to real data.

Features

• Import OWL/RDF ontologies and metadata in standard RDF formats (RDF/XML, Turtle, N‑Triples, JSON‑LD, …)
• Build a SHACL‑based, ontology‑aware Application Profile (AP)
• Create, import, edit, delete, and validate linked data against the AP and ontologies
• Generate a profile automatically from existing metadata
• Explore the dataset publicly with label‑first display and an interactive graph
• Switch between dark, light, and system theme modes
• Extend the system with plugins and themes
• Progressive Web App (PWA)

Semantta is domain‑independent and can host data from any domain.

Used Technologies

Layer	Technology
Data	RDF, RDFS, OWL, SHACL, XSD, SPARQL
Backend	FastAPI, rdflib, owlrl, pyshacl, httpx
Frontend	Nuxt 4 (Vue 3, TypeScript), Pinia, Tailwind CSS 4, SortableJS, vis‑network, Phosphor Icons, vue‑sonner

Prerequisites

• Python 3.10+ with pip
• Node.js 18+ with npm
• Apache Jena Fuseki 5+ (requires Java 17+)

Getting Started

1. Get Semantta

clone the repository:

git clone https://github.com/eaoui/semantta.git
cd semantta

or just download a release.

2. Start a Fuseki Dataset

Start an existing (or create a new) Fuseki dataset by running the fuseki-server script with a TDB2 location:

# Linux/Mac
./fuseki-server --update --tdb2 --loc /path/to/database /dataset_name

# Windows
.\fuseki-server --update --tdb2 --loc path\to\database /dataset_name

The default port is 3030 and the default dataset name is obmms.
If you use a different port or name, set FUSEKI_DATASET_URL in a backend/.env file:

cd backend
cp .env.example .env  # Windows: copy .env.example .evn
# then edit FUSEKI_DATASET_URL

3. Run the Backend

# 1. move to the /backend directory
cd backend

# 2. create a virtual environment named .venv
python -m venv .venv

# 3. activate the virtual environment
source .venv/bin/activate   # Windows: .venv\Scripts\activate

# 4. install Python dependencies
pip install -r requirements.txt

# 5. start the API server (default port number is 8000)
uvicorn main:app --host 0.0.0.0 --port 8000 --reload

Next time you only need stepts 1, 3, and 5.

4. Run the Frontend

# 1. move to the /frontend directory
cd frontend

# 2. install Node.js packages
npm install

# 3. start the development server
npm run dev

Next time you only need steps 1 and 3.

The app will be available at http://localhost:3000.

Basic Workflow

1. Import an ontology: Upload an RDF/XML, Turtle, or other supported format via the admin interface. The system applies OWL‑RL reasoning and caches the result.
2. Build the Application Profile: Open the “Application Profile” page, activate the entities you need, and fine‑tune the SHACL constraints.
3. Create or import metadata: Create instances manually via the dynamic form, or upload RDF-based metadata files. Instances are validated against the AP.
4. Explore publicly: You can search or browser the existing dataset. The /dataset page indexes all instances. Click any instance to see its description, syntax, and interactive graph.

Project Structure

semantta/
├── backend/
│   ├── main.py              # FastAPI app, endpoints, core logic
│   ├── fuseki_store.py      # Async Fuseki client
│   ├── utils.py             # URI helpers
│   ├── vocab/               # OWL vocabulary for reasoning
│   ├── data/                # Runtime data (cache, uploads, settings)
│   └── plugins/             # User‑installed plugins
├── frontend/
│   └── app/
│       ├── components/      # Vue components
│       ├── composables/     # Reusable logic
│       ├── layouts/         # Admin and public layouts
│       ├── pages/           # Nuxt pages (admin & public)
│       ├── stores/          # Pinia store
│       ├── types/           # TypeScript interfaces
│       └── ...
└── docs

Contributing

Contributions are welcome! Please open an issue to discuss your idea before submitting a pull request.

License

Semantta is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

Applications

Have you built a public project on top of Semantta? Add it below!

• Example Application Name

Screenshots

Admin

Public

View all screenshots in docs/screenshots