View Source Listen to PubSub Events

As mentioned in the installation guide you need to configure PubSub for your LiveResources. Backpex will use the configuration to publish deleted, updated and created events. Backpex will listen to these events and update the UI accordingly. Sometimes you may want to listen to these events and perform some custom actions. For example you want to show a toast to all users currently on the resource that a post has been created.

Configuration

You can listen for Backpex PubSub events by implementing the Phoenix.LiveView handle_info/2 callback in your LiveResource module.

We assume you configured PubSub for your Posts LiveResource like this:

use Backpex.LiveResource,
    ...,
    pubsub: [
        name: Demo.PubSub
        topic: "posts",
        event_prefix: "post_"
    ]

You could implement the following handle_info/2 callbacks in your LiveResource:

# in your resource configuration file

@impl Phoenix.LiveView
def handle_info({"post_created", item}, socket) do
    # make something in response to the event
    {:noreply, socket}
end

@impl Phoenix.LiveView
def handle_info({"post_updated", item}, socket) do
    # make something in response to the event
    {:noreply, socket}
end

@impl Phoenix.LiveView
def handle_info({"post_deleted", item}, socket) do
    # make something in response to the event
    {:noreply, socket}
end