flycast

flycast implements persevering UDP broadcasting for apps running on Fly.

It does so by accepting UDP packets on two configurable port numbers and by re-sending those packets to global or regional (depending on the intercepting port) instances of a configurable target app via the organization's internal network.

flycast discovers the instances it should broadcast to automatically, via querying Fly's internal DNS, and very frequently (currently every second) and comes with an embedded HTTP server that exports a complete health check.

An example deployment configuration can be found in the fly.example.toml file of this repo.

Disclaimer

• This here program works not, maybe possibly, yet.
• 16384 bytes, or 16 KiB, is the maximum UDP packet size flycast can handle.

Configuration

flycast is configured via the following environment variables:

Variable	Description	Default value
$APP	Fly app to broadcast to.	$FLY_APP_NAME
$PORT_GLOBAL	Packets arriving on this port will be broadcasted to all instances of $APP.	65535
$PORT_LOCAL	Packets arriving on this port will be broadcasted to instances of $APP in the same region they were intercepted in.	65534
$PORT_RELAY	flycast will broadcast packets to this port.	65533
$PORT_HTTP	The embedded web browser will run on this port with the health check accessible under /health.	8080
$LOG_LEVEL	Controls the verbosity of the logger. Valid values are debug, info, warn, error.	info
$LOG_FORMAT	When set to json instructs the logger to output JSON objects instead of raw text.	N/A