Another kiosk browser OS? Yes, this one is a little bit opinionated :)
The author ran several similar setups in production for years and has seen a lot of problems and strange failure modes.
This project aims to solve a lot of those (at least for the author), it might also be useful for others :)
- Images built via CI
- WiFi connection support
- Raspberry Pi (Arm64) compatibility
- PC (x86) compatibility
- USB flash drive, USB SSD, etc. compatible
- aarch64 mode for Raspberry Pis (significant performance improvements over armv7/32bit ARM)
- Read-only filesystem handling (no more broken SD cards)
- Configurable cache clear functionality
- HTTP watchdog (website needs to send heartbeat messages via XHR/AJAX to localhost)
- Force specific resolution (1080p on 4k screens, broken EDID, etc.)
- Hard NTP handling (will wait for NTP at boot)
- SSH support
- VNC support
- SSH tunneling support (for remote-access without port-forwarding, etc.)
- Raspberry Pi PXE/network boot support
- Network connectivity watchdog (configurable ping, etc. timeout)
- Automatic reboot at specified time
- Autossh does not check SSH host keys. This is okay-ish as long as the target server only allows tunneling, nothing else.
- nginx/PHP are allowed to use sudo/NOPASSWD (because it needs to query the VideoCore, manage service, etc.), more priviledge seperation would be nice
- due to the skeleton mechanism, the system has some ... creative permissions. some cleanup required.
Like any other Raspberry Pi image: download the current .img file from the Releases page and flash it to a storage device of your choice.
SD cards, USB flash drives, USB SSDs, SATA SSDs, NVMe SSDs are all good options.
You can use a tool like the Raspberry Pi Imager, BalenaEtcher, Win32DiskImager or plain "dd" on *nix-like systems.
When using the latter two, make sure to extract the .gz compression first (using a tool like 7zip).
After flashing, re-plug the storage device and open the FAT32 partition.
Open the kioskbrowser.ini file in a text editor and change everything to your needs.
More complex WiFi setups (like WPA2-Enterprise) can be configured by creating a wpa_supplicant.conf.
Adding your own SSH keys can be done by creating a authorized_keys file.
If you want to use the autossh tunneling features, copy an SSH private key as either "id_rsa" or "id_ed25519".
Browsers are complex, networks are unstable and software can be buggy.
In order to get the highest reliability possible, self-hosted websites can be modified to include a heartbeat/watchdog functionality.
This works by requesting a certain http-endpoint from the website at some interval.
If your page is being reloaded often (like with a <meta refresh=-header), you can just load the heartbeat-URL as an image:
<img src="http://localhost/heartbeat.php" style="display: none;">If your page stays on one page for a long time (or is just a single-page application), you might want to use AJAX requests to send a heartbeat:
<script>
const req = new XMLHttpRequest();
setInterval(function() {
req.open("GET", "http://localhost/heartbeat.php");
req.send();
}, 2000);
</script>Whenever the heartbeat stops (for whatever reason), the device will first restart the X11 environment (browser, window manager, etc.) and later (if it hasn't recovered) the whole system by rebooting.