Redix PubSub

Elixir library for Redis Pub/Sub (based on Redix)

Installation

Add the :redix_pubsub dependency to your mix.exs file:

defp deps() do
  [{:redix_pubsub, ">= 0.0.0"}]
end

and add :redix_pubsub to your list of applications:

defp application() do
  [applications: [:logger, :redix_pubsub]]
end

Then, run mix deps.get in your shell to fetch the new dependency.

Usage

Each Redix.PubSub process is able to subcribe to/unsubscribe from multiple Redis channels, and is able to handle multiple Elixir processes subscribing each to different channels.

A Redix.PubSub process can be started via Redix.PubSub.start_link/2:

{:ok, pubsub} = Redix.PubSub.start_link()

This process will hold a single TCP connection to Redis. All other communication happens via Elixir messages (that simulate a Pub/Sub interaction with the Redix.PubSub process). Subscribing (to channels and patterns) as well as unsubscribing work as fire-and-forget operations (casts in GenServer-speak) that always return :ok: the subscription/unsubscription confirmation comes as an Elixir message.

{:ok, pubsub} = Redix.PubSub.start_link()

Redix.PubSub.subscribe(pubsub, "my_channel", self())
#=> :ok

# Now, messages will be sent to the current process. Let's wait for the
# subscription confirmation:
receive do
  {:redix_pubsub, ^pubsub, :subscribed, %{channel: "my_channel"}} -> :ok
end

# Now, someone publishes "hello" on "my_channel":
receive do
  {:redix_pubsub, ^pubsub, :message, %{channel: "my_channel", payload: "hello"}} ->
    IO.puts "Received a message!"
end

More information on usage of this library can be found in the documentation.

License

ISC 2016, Andrea Leopardi (see LICENSE.txt)