Module protocol 

XLX UDP JSON monitor protocol message types.

XLX reflectors (xlxd) expose a UDP push-notification interface on port 10001 for real-time activity monitoring. The protocol is simple:

1. Client sends "hello" as a UDP datagram to the reflector’s IP on port 10001.
2. The server responds with three separate UDP datagrams, each containing one JSON object:
   • MonitorMessage::Reflector: reflector identity and available modules.
   • MonitorMessage::Nodes: snapshot of all currently connected nodes.
   • MonitorMessage::Stations: snapshot of recently heard stations.
3. After the initial dump, the server pushes updates as events occur:
   • MonitorMessage::Nodes: whenever a node connects or disconnects.
   • MonitorMessage::Stations: whenever a station is heard.
   • MonitorMessage::OnAir: when a station starts transmitting.
   • MonitorMessage::OffAir: when a station stops transmitting.
4. Client sends "bye" to disconnect cleanly.

Each UDP datagram contains exactly one complete JSON object (no framing, no length prefix). The maximum node dump is 250 entries per datagram, and the server’s update period is approximately 10 seconds.

Parsing strategy

Because all messages arrive as untagged JSON objects, parse attempts to deserialize each shape in a specific order. The order matters because some shapes are subsets of others — for example, a {"nodes":[...]} object would match both the nodes shape and a hypothetical catch-all. The parse order is:

1. OnAir / OffAir — smallest, most distinctive keys.
2. Reflector — has the unique "reflector" + "modules" combination.
3. Nodes — has the "nodes" array key.
4. Stations — has the "stations" array key.
5. Unknown — fallback for unrecognized messages (logged, not fatal).

Structs

NodeInfo 🔒

A single connected node entry from the "nodes" array.

NodesMsg 🔒

Helper for {"nodes":[...]}.

OffAirMsg 🔒

Helper for {"offair":"CALLSIGN"}.

OnAirMsg 🔒

Helper for {"onair":"CALLSIGN"}.

ReflectorInfo 🔒

Identity and module list for a reflector.

ReflectorMsg 🔒

Helper for {"reflector":"...","modules":[...]}.

StationInfo 🔒

A single heard station entry from the "stations" array.

StationsMsg 🔒

Helper for {"stations":[...]}.

Enums

MonitorMessage 🔒

A parsed XLX monitor protocol message.

Functions

parse 🔒

Attempts to parse a raw UDP datagram payload into a MonitorMessage.