Dynawo GUI

Web interface for Dynawo power-system simulations.

Built with FastAPI (backend) + React/Vite (frontend).

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Quick start (Linux/macOS)

Two scripts wrap the full dev setup:

./install.sh   # create the venv, install backend + frontend dependencies
./run.sh       # start both servers; open http://localhost:5173

install.sh checks prerequisites (Python ≥ 3.10, Node ≥ 18), verifies the package registries (PyPI, npm) are reachable — stopping with a proxy hint if not — and tells you how to install anything missing. run.sh launches the backend and the Vite dev server together and stops both on Ctrl+C. Environment variables (see below) are passed through, e.g. SESSION_TTL=7200 ./run.sh.

To reset a broken or stale install, re-run with --clean, which removes the virtual environment and the frontend dependencies before reinstalling:

./install.sh --clean   # delete .venv and frontend/node_modules,
                       # then reinstall

The tracked frontend/package-lock.json is kept (so dependencies reinstall at their committed versions), and downloaded Dynawo versions under ~/.config/dynawo_ihm/ are left untouched.

Prefer to run the steps yourself? See the manual instructions below.

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Quick start (Windows, via Docker)

Dynawo's binaries are Linux-first, so on Windows the application runs inside a Linux container. Everything it needs — Python, Node, Dynawo and DynaFlow Launcher — is in the image, so Docker is the only thing to install.

1. Install Docker Desktop, keeping the WSL2 backend enabled (the default), and start it.
2. Double-click start-dynawo-gui.bat in this folder.
3. When it says the application is running, open http://localhost:8080.

The first run builds the images and takes 10–25 minutes; later runs take seconds. Double-click stop-dynawo-gui.bat to stop — your simulation data is kept in a Docker volume and survives restarts.

The launcher checks that Docker is installed and actually running, builds only when needed, waits until the application answers, and opens your browser on it. If something is missing it prints exactly what to do.

No Dynawo download is needed: every Linux release listed in resources/dynawo_versions.json and resources/dynaflow_versions.json is already inside the image, so the app also works without internet access.

On Linux or macOS the same setup runs via docker/start.sh and docker/stop.sh, or directly with docker compose up -d --build. Use GUI_PORT=9090 to serve on a different port.

If Docker Desktop is not available to you, Rancher Desktop runs this setup unchanged.

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Project structure

dynawo_IHM/
├── api/                  # FastAPI backend
│   ├── main.py           # App entry point
│   ├── session_store.py  # Server-side session management
│   ├── dependencies.py   # FastAPI Depends() helpers
│   └── routers/          # One file per feature area
│       ├── admin.py
│       ├── auth.py
│       ├── files.py
│       ├── network.py
│       ├── parameters.py
│       ├── simulation.py
│       ├── solver.py
│       └── dynawo_version.py
├── backend/              # Shared business logic (Python library)
├── frontend/             # React + Vite frontend
│   └── src/
│       ├── pages/        # One file per page
│       └── api/          # Axios client
└── requirements.txt      # Python dependencies

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Requirements

Python

• Python ≥ 3.10
• A virtual environment is recommended (python3 -m venv .venv)

Node (React frontend only)

• Node ≥ 18 — install locally with nvm:

  curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.39.7/install.sh | bash
  source ~/.bashrc
  nvm install --lts

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Install

Backend

python3 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

Frontend

cd frontend
npm install

Clean install: if you need to reset the frontend dependencies from scratch (e.g. after a package.json change or a broken node_modules), use:

cd frontend
rm -rf node_modules package-lock.json
npm install

Do not use npm ci — it skips optional native dependencies and breaks the Vite dev server (rolldown binding error).

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Run

Backend

Run from the repo root (dynawo_IHM/):

source .venv/bin/activate
uvicorn api.main:app --reload --port 8000

Swagger UI available at http://localhost:8000/docs.

Frontend (development)

In a second terminal:

cd frontend
npm run dev

Opens at http://localhost:5173. All /api/* requests are proxied to FastAPI on port 8000 — both servers must be running.

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Typical workflow

1. Start both servers (see above)
2. Open http://localhost:5173
3. Go to Dynawo Version → set or download a Dynawo executable
   • To use a local Dynawo install, point this to the executable inside a Dynawo deploy or distribution folder (the one containing the ddb/ directory alongside bin/) — the app looks up model description files (.desc.xml) in ddb/ relative to the executable path
4. Go to Upload Files → drag and drop your .jobs, .dyd, .par, .iidm, .crv files
5. Load the .iidm network to see the component count summary
6. Go to Network View → explore the network diagram and voltage levels
7. Go to Edit Parameters → select a dynamic model and edit its parameters; use Revert on individual change-log entries to undo a specific edit, or Restore original to go back to the uploaded file
8. Go to Edit Solver Parameters → adjust solver settings the same way
9. Go to Run Simulation → run and inspect output curves; use Download Files in the sidebar to export all input files and results as a ZIP

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Environment variables

Variable	Default	Description
SESSION_TTL	3600	Seconds of inactivity before a session is evicted and its temp dir deleted
MAX_CONCURRENT_SIMS	4	Maximum number of Dynawo processes that can run simultaneously across all users
MAX_CONCURRENT_PYPOWSYBL	4	Maximum number of simultaneous pypowsybl-heavy operations (NAD/SLD/diff rendering, load flow runs) across all users; excess requests get an immediate 503
PYPOWSYBL_WORKERS	2	Number of persistent worker processes used to run load flows (OpenLoadFlow/DynaFlow) in parallel, each with its own embedded JVM
ADMIN_KEY	—	If set, GET /api/admin/sessions requires this value in the X-Admin-Key header
DYNAWO_DEFAULT_EXE	—	Pre-set Dynawo executable path for all sessions
STANDALONE	0	Set to 1 to allow absolute output directory paths (local single-user use only)

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Development notes

• backend/ is the shared Python library — imported by api/ and never duplicated
• Sessions are anonymous and auto-created on first request; each browser tab gets its own isolated workspace
• Session data (uploaded files, network object, run history) lives in memory and is cleaned up after SESSION_TTL seconds of inactivity

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Get involved!

Dynawo GUI is an open-source project and as such, questions, discussions, feedbacks and more generally any form of contribution are very welcome and greatly appreciated! For further informations about contributing guidelines, please refers to the contributing documentation.

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Maintainers

Dynawo GUI is currently maintained by the following people in RTE:

• Gilles Aouizerate, gilles.aouizerate@rte-france.com
• Marco Chiaramello, marco.chiaramello@rte-france.com
• Julien De Sloovere, julien.desloovere@rte-france.com
• Joy El-Feghali, joy.elfeghali@rte-france.com
• Baptiste Letellier, baptiste.letellier@rte-france.com
• Sylvestre Prabakaran, sylvestre.prabakaran@rte-france.com
• Florentine Rosiere, florentine.rosiere@rte-france.com
• Thibaut Vermeulen, thibaut.vermeulen@rte-france.com

In case of questions or issues, you can also send an e-mail to rte-dynawo@rte-france.com.