Flask Digital Signage (simple)

Lightweight digital signage platform using Flask + SQLite.

Features

• Central admin can manage companies, users, displays.
• Admin can impersonate any company user (no password).
• Company users can:
  • Create playlists
  • Add slides (image/video/webpage)
  • Assign playlists to displays
• Displays are public 16:9 player webpages suitable for kiosk browsers.

Quickstart (Windows)

python -m venv .venv
.venv\Scripts\activate
pip install -r requirements.txt

set FLASK_APP=app
flask init-db --admin-email beheer@alphen.cloud --admin-pass admin
flask run --debug

If Flask can't discover the app automatically, use:

set FLASK_APP=app:create_app
flask run --debug

Open http://127.0.0.1:5000

Notes

• SQLite DB is stored at instance/signage.sqlite.
• Uploaded files go to app/static/uploads/.

Display player

Open:

• http://<host>/display/<token> for live playback (counts towards the concurrent display limit)
• http://<host>/display/<token>?preview=1 for preview (does not count towards the concurrent display limit)

Live updates

The player keeps itself up-to-date automatically:

• It listens to GET /api/display/<token>/events (Server-Sent Events) and reloads the playlist immediately when it changes.
• It also does a fallback playlist refresh every 5 minutes for networks/proxies that block SSE.

SMTP / Forgot password

This project includes a simple forgot password flow. SMTP configuration is read from environment variables.

You can also configure SMTP settings from the UI: Admin → Settings. Environment variables still take precedence over the database settings.

Public domain for emails

If your app runs behind a reverse proxy (or the internal hostname differs from the public hostname), set Admin → Settings → Public domain to e.g. signage.example.com so links in password reset emails point to the correct address.

Recommended: put these in a local .env file in the repo root. Flask (via python-dotenv) will auto-load it on startup. .env is already gitignored.

You can start from .env.example:

copy .env.example .env

Example

REM Option A: set env vars in the same terminal where you run `flask run`
set SMTP_HOST=smtp.strato.de
set SMTP_PORT=587
set SMTP_USERNAME=beheer@alphen.cloud
set SMTP_PASSWORD=***
set SMTP_FROM=beheer@alphen.cloud
set SMTP_STARTTLS=1
set SMTP_DEBUG=1

REM Option B: put the same keys/values in a .env file instead

Security note: do not commit SMTP passwords to the repo. Prefer secrets management and rotate leaked credentials.

Note on the "From" address: some SMTP providers enforce that the authenticated mailbox (SMTP_USERNAME) is used as the actual sender (envelope-from), even if a different SMTP_FROM is provided. In that case the app sets a Reply-To header so replies still go to SMTP_FROM, but the provider may still show the username address as the sender.

Troubleshooting mail delivery

If the reset email is not received:

1. Set SMTP_DEBUG=1 and request a reset again.
2. Watch the Flask console output for SMTP responses / errors.
3. Verify:
   • SMTP_USERNAME and SMTP_FROM are allowed by your provider.
   • You are using STARTTLS (port 587).
   • The recipient mailbox isn’t filtering it (spam/quarantine).