beryl/group

Channel Groups - Named collections of topics for multi-topic broadcasting

Groups let you organize topics and broadcast to all of them at once. Useful for scenarios like broadcasting to all channels in a "team" or sending a system-wide notification.

When running beryl under beryl/supervisor, enable groups with supervisor.with_groups and obtain the handle from supervisor.groups instead of calling start directly.

Example

let assert Ok(groups) = group.start()
let assert Ok(Nil) = group.create(groups, "team:engineering")
let assert Ok(Nil) = group.add(groups, "team:engineering", "room:frontend")
let assert Ok(Nil) = group.add(groups, "team:engineering", "room:backend")
group.broadcast(groups, channels, "team:engineering", "announce", payload)

Types

GroupError

Errors from group operations

pub type GroupError {
  GroupAlreadyExists
  GroupNotFound
}

Constructors

GroupAlreadyExists

The group already exists

GroupNotFound

The group was not found

Groups

A running Groups instance.

This handle is intentionally opaque so callers cannot forge the backing actor subject or depend on its runtime representation.

pub type Groups

GroupStartError

Errors when starting the groups actor.

pub type GroupStartError {
  GroupActorStartFailed(error.StartFailure)
}

Constructors

GroupActorStartFailed(error.StartFailure)

The actor failed to start

Message

Messages the groups actor handles

pub type Message

Functions

add

Add a topic to a group

Panics if the groups actor is unavailable or does not reply within 5 seconds.

pub fn add(
  Groups,
  String,
  String
) -> Result(Nil, GroupError)

broadcast

Broadcast a message to all topics in a group

Sends the message to every topic in the named group via beryl.broadcast(). If the group doesn't exist, this is a silent no-op (fire and forget).

pub fn broadcast(
  Groups,
  beryl.Channels,
  String,
  String,
  json.Json
) -> Nil

create

Create a new named group

Panics if the groups actor is unavailable or does not reply within 5 seconds.

pub fn create(
  Groups,
  String
) -> Result(Nil, GroupError)

delete

Delete a group

Panics if the groups actor is unavailable or does not reply within 5 seconds.

pub fn delete(
  Groups,
  String
) -> Result(Nil, GroupError)

list_groups

List all group names

Panics if the groups actor is unavailable or does not reply within 5 seconds.

pub fn list_groups(Groups) -> List(String)

remove

Remove a topic from a group

Panics if the groups actor is unavailable or does not reply within 5 seconds.

pub fn remove(
  Groups,
  String,
  String
) -> Result(Nil, GroupError)

start

Start the groups actor

pub fn start() -> Result(Groups, GroupStartError)

topics

Get all topics in a group

Panics if the groups actor is unavailable or does not reply within 5 seconds.

pub fn topics(
  Groups,
  String
) -> Result(set.Set(String), GroupError)