Phoenix LiveSession

LiveSession provides in-memory sessions for LiveViews and Phoenix controllers.

You can use them like regular Plug sessions in Phoenix controllers and have full read/write access to session data from LiveViews - including updates via Phoenix.PubSub.

Installation

1. Add this project to your mix.exs as a dependency: {:phoenix_live_session, "~> 0.1"},
2. Add PhoenixLiveSession as store for Plug.Session:

    # lib/my_app_web/endpoint.ex
      @session_options [
          store: PhoenixLiveSession,
          pub_sub: MyApp.PubSub,
          signing_salt: "your-salt",
          key: "session"
      ]

Usage

Usage in Phoenix Controllers

You don’t need to do anything special to use LiveSessions in regular Phoenix controllers. Your sessions will continue to work the same as with other stores.

Usage in LiveViews

Use maybe_subscribe/2 in your mount/3 function to subscribe to LiveSession updates. Only sockets for which Phoenix.LiveView.connected?/1 returns true are subscribed by maybe_subscribe/2.

Once you’ve subscribed to a LiveSession, you can handle session updates with handle_info/2 and push session updates with put_session/3.

Usage in LiveComponents

You can also use LiveSessions without subscribing to them in a LiveView.

In that case, you can directly use the session data structure from the mount/3 callback to use put_session/3.

Example

defmodule ShoppingCartLive
  use MyAppWeb, :live_view

  def mount(_params, session, socket) do
    socket = socket
    |> PhoenixLiveSession.maybe_subscribe(session)
    |> put_session_assigns(session)

    {:ok, socket}
  end

  def handle_info({:live_session_updated, session}, socket) do
    {:noreply, put_session_assigns(socket, session)}
  end

  def handle_event("add_to_cart", %{"product_id" => product_id}, socket) do
    updated_cart = [product_id | socket.assigns.cart]
    PhoenixLiveSession.put_session(socket, "cart", updated_cart)

    {:noreply, socket}
  end

  defp put_session_assigns(socket, session) do
    socket
    |> assign(:shopping_cart, Map.get(session, "shopping_cart", []))
  end
end

License

Copyright 2013 Plataformatec. Copyright 2020 Pentacent.

Licensed under the Apache License, Version 2.0 (the "License"); You may not use any files in this repository except in compliance with the License. You may find a copy of the License in the LICENSE file.

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.