View Source Yggdrasil.Backend behaviour (Yggdrasil v6.0.3)
Backend behaviour that defines how to subscribe, unsubscribe and publish as well as send messages of connection and disconnection to subscribers.
By default, the implementation uses Phoenix.PubSub as backend.
backend-alias
Backend alias
When defining backends it is possible to define aliases for the module as follows:
defmodule Yggdrasil.Backend.MyBackend do
use Yggdrasil.Backend, name: :my_backend
(... behaviour implementation ...)
endAnd adding the following to our application supervision tree:
Supervisor.start_link([
{Yggdrasil.Backend.MyBackend, []}
...
])This will allow you to use the following as a Channel to subscribe and
publish:
%Channel{name: "my_channel", backend: :my_backend}Link to this section Summary
Callbacks
Callback to publish the connected message in the channel. Receives a pid
in case the message shouldn't be broadcasted.
Callback to publish the disconnected message in the channel. Receives a
pid in case the message shouldn't be broadcasted.
Callback to publish a message in a channel with some metadata.
Callback to define the subscription method. Receives the channel.
Callback to define the unsubscription method. Receives the channel.
Functions
Macro for using Yggdrasil.Backend.
Generic connected message sender to a channel. Optionally receives
the pid of the specific subscriber.
Generic disconnected message sender to a channel. Optionally receives
the pid of the specific subscriber.
Generic publish message in a channel with some optional metadata.
Generic subscription in a channel.
Transforms name of the channel to a binary.
Generic unsubscriptions in a channel.
Link to this section Callbacks
@callback connected(channel :: Yggdrasil.Channel.t(), pid :: atom() | pid()) :: :ok | {:error, term()}
Callback to publish the connected message in the channel. Receives a pid
in case the message shouldn't be broadcasted.
@callback disconnected(channel :: Yggdrasil.Channel.t(), pid :: atom() | pid()) :: :ok | {:error, term()}
Callback to publish the disconnected message in the channel. Receives a
pid in case the message shouldn't be broadcasted.
@callback publish( channel :: Yggdrasil.Channel.t(), message :: term(), metadata :: term() ) :: :ok | {:error, term()}
Callback to publish a message in a channel with some metadata.
@callback subscribe(channel :: Yggdrasil.Channel.t()) :: :ok | {:error, term()}
Callback to define the subscription method. Receives the channel.
@callback unsubscribe(channel :: Yggdrasil.Channel.t()) :: :ok | {:error, term()}
Callback to define the unsubscription method. Receives the channel.
Link to this section Functions
Macro for using Yggdrasil.Backend.
The following are the available options:
:name- Name of the backend. Must be an atom.
@spec connected(Yggdrasil.Channel.t(), nil | pid()) :: :ok | {:error, term()}
Generic connected message sender to a channel. Optionally receives
the pid of the specific subscriber.
@spec disconnected(Yggdrasil.Channel.t(), nil | pid()) :: :ok | {:error, term()}
Generic disconnected message sender to a channel. Optionally receives
the pid of the specific subscriber.
@spec publish(Yggdrasil.Channel.t(), term(), term()) :: :ok | {:error, term()}
Generic publish message in a channel with some optional metadata.
@spec subscribe(Yggdrasil.Channel.t()) :: :ok | {:error, term()}
Generic subscription in a channel.
@spec transform_name(Yggdrasil.Channel.t()) :: binary()
Transforms name of the channel to a binary.
@spec unsubscribe(Yggdrasil.Channel.t()) :: :ok | {:error, term()}
Generic unsubscriptions in a channel.