app.py

from h2o_wave import main, app, Q, ui


@app('/')
async def serve(q: Q):
    # Use app scope to make sure the file is uploaded only once.
    if not q.app.initialized:
        # Upload the file to the Wave server.
        download_path, = await q.site.upload(['dataset.csv'])
        q.app.initialized = True

    # TODO: Draw a UI to allow file downloads.
    await q.page.save()