# `Cardbox.Event`
[🔗](https://github.com/hattoriai/cardbox/blob/v0.1.0/lib/cardbox/event.ex#L1)

A change to a collection, broadcast to everyone who has it open.

    MyApp.Cardbox.subscribe(collection)

    def handle_info({:cardbox, %Cardbox.Event{type: :record_updated, record: record}}, socket)

`type` is one of `:record_inserted`, `:record_updated`, `:record_moved`,
`:record_deleted`, `:field_added`, `:field_updated`, `:field_moved`,
`:field_deleted`, `:view_saved`, `:view_deleted`, `:collection_updated`
and `:collection_deleted`.

A record's event has the `record` as it is after (as it was, for a
deletion) and, for an update, the keys of the fields that `changed`. A
field's or a collection's event has the `collection` as it is after,
with its fields, so a view takes the new fields without reading them
again. `actor` is the id of who made the change.

Each event is also a `:telemetry` event, `[:cardbox, :change]`, with the
event in its metadata.

# `t`

```elixir
@type t() :: %Cardbox.Event{
  actor: String.t() | nil,
  changed: [String.t()],
  collection: Cardbox.Collection.t() | nil,
  collection_id: integer(),
  field: Cardbox.Field.t() | nil,
  record: Cardbox.Record.t() | nil,
  type: type(),
  view: Cardbox.View.t() | nil
}
```

# `type`

```elixir
@type type() ::
  :record_inserted
  | :record_updated
  | :record_moved
  | :record_deleted
  | :field_added
  | :field_updated
  | :field_moved
  | :field_deleted
  | :view_saved
  | :view_deleted
  | :collection_updated
  | :collection_deleted
```

# `topic`

```elixir
@spec topic(Cardbox.Collection.t() | integer()) :: String.t()
```

The PubSub topic of a collection's events.

---

*Consult [api-reference.md](api-reference.md) for complete listing*