beryl/presence/wire

Phoenix-compatible wire encoding for presence diffs.

Functions

encode_diff

Encode a presence diff for one topic as a Phoenix-compatible payload.

The resulting JSON has joins and leaves maps keyed by presence key, where each value contains the tracked metadata under metas.

{
  "joins": { "user:1": { "metas": [{ "status": "online" }] } },
  "leaves": { "user:2": { "metas": [{ "status": "offline" }] } }
}

pub fn encode_diff(
  presence.Diff,
  String
) -> json.Json

encode_state

Encode a topic's full presence list as a Phoenix-compatible presence_state payload.

The resulting JSON is a map keyed by presence key, where each value contains the tracked metadata under metas — the same shape as one side of a presence_diff:

{ "user:1": { "metas": [{ "status": "online", "phx_ref": "..." }] } }

Phoenix clients expect a presence_state event carrying this payload after joining a presence-enabled topic (followed by incremental presence_diff events). Build the entry list with presence.list.

pub fn encode_state(List(presence.PresenceEntry)) -> json.Json