List users for chat

lib/ex338/application.ex

@@ -26,6 +26,7 @@ defmodule Ex338.Application do
       Ex338.Repo,
       {Phoenix.PubSub, pubsub_options},
       Ex338Web.Telemetry,
+      Ex338Web.Presence,
       # Start the endpoint when the application starts
       Ex338Web.Endpoint,
       {Oban, Application.fetch_env!(:ex338, Oban)}

lib/ex338/chats.ex

@@ -58,6 +58,6 @@ defmodule Ex338.Chats do
     Phoenix.PubSub.broadcast(Ex338.PubSub, topic(message), {__MODULE__, event})
   end
 
-  defp topic(%Message{} = message), do: "chat:#{message.chat_id}"
-  defp topic(%Chat{} = chat), do: "chat:#{chat.id}"
+  def topic(%Message{} = message), do: "chat:#{message.chat_id}"
+  def topic(%Chat{} = chat), do: "chat:#{chat.id}"
 end

lib/ex338_web/live/championship_live/chat_component.ex

@@ -52,83 +52,38 @@ defmodule Ex338Web.ChampionshipLive.ChatComponent do
   @impl true
   def render(assigns) do
     ~H"""
-    <div class="overflow-hidden bg-white shadow sm:rounded-lg">
-      <div class="py-5 border-b border-gray-200">
-        <ul
-          id="messages"
-          phx-update="stream"
-          role="list"
-          phx-hook="ChatScrollToBottom"
-          class="flex flex-col h-[800px] overflow-y-auto overflow-x-hidden pb-6"
-        >
-          <.comment :for={{id, message} <- @messages} id={id} message={message} />
-        </ul>
-
-        <div class="flex gap-x-3 px-4 sm:px-6">
-          <.user_icon name={@current_user.name} class="!mt-0" />
-          <.form
-            id="create-message"
-            for={@form}
-            phx-target={@myself}
-            phx-change="validate"
-            phx-submit="save"
-            class="relative flex-auto"
-          >
-            <div class="overflow-hidden rounded-lg pb-12 shadow-sm ring-1 ring-inset ring-gray-300 focus-within:ring-2 focus-within:ring-indigo-600">
-              <label for="comment" class="sr-only">Add your comment</label>
-              <.input
-                field={@form[:content]}
-                phx-debounce="blur"
-                type="commenttextarea"
-                rows="2"
-                class="block w-full resize-none border-0 bg-transparent py-1.5 text-gray-900 placeholder:text-gray-400 focus:ring-0 sm:text-sm sm:leading-6"
-                placeholder="Add your comment..."
-              />
-            </div>
-
-            <div class="absolute inset-x-0 bottom-0 flex justify-end py-2 pl-3 pr-2">
-              <button
-                type="submit"
-                class="rounded-md bg-white px-2.5 py-1.5 text-sm font-semibold text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 hover:bg-gray-50"
-              >
-                Comment
-              </button>
-            </div>
-          </.form>
+    <div class="flex gap-x-3 px-4 sm:px-6">
+      <.user_icon name={@current_user.name} class="!mt-0" />
+      <.form
+        id="create-message"
+        for={@form}
+        phx-target={@myself}
+        phx-change="validate"
+        phx-submit="save"
+        class="relative flex-auto"
+      >
+        <div class="overflow-hidden rounded-lg pb-12 shadow-sm ring-1 ring-inset ring-gray-300 focus-within:ring-2 focus-within:ring-indigo-600">
+          <label for="comment" class="sr-only">Add your comment</label>
+          <.input
+            field={@form[:content]}
+            phx-debounce="blur"
+            type="commenttextarea"
+            rows="2"
+            class="block w-full resize-none border-0 bg-transparent py-1.5 text-gray-900 placeholder:text-gray-400 focus:ring-0 sm:text-sm sm:leading-6"
+            placeholder="Add your comment..."
+          />
         </div>
-      </div>
-    </div>
-    """
-  end
 
-  defp comment(%{message: %{user: nil}} = assigns) do
-    ~H"""
-    <li id={@id} class="flex gap-x-4 hover:bg-gray-50 px-4 sm:px-6 py-2">
-      <div class="flex h-6 w-6 flex-none items-center justify-center">
-        <.icon name="hero-check-circle" class="h-6 w-6 text-indigo-600" />
-      </div>
-      <p class="flex-auto py-0.5 text-xs leading-5 text-gray-500">
-        <%= @message.content %>
-      </p>
-    </li>
-    """
-  end
-
-  defp comment(assigns) do
-    ~H"""
-    <li id={@id} class="flex gap-x-4 hover:bg-gray-50 px-4 sm:px-6 py-2">
-      <.user_icon name={@message.user.name} />
-      <div class="flex-auto">
-        <div class="flex justify-between items-start gap-x-4">
-          <div class="text-xs leading-5 font-medium text-gray-900">
-            <%= @message.user.name %>
-          </div>
+        <div class="absolute inset-x-0 bottom-0 flex justify-end py-2 pl-3 pr-2">
+          <button
+            type="submit"
+            class="rounded-md bg-white px-2.5 py-1.5 text-sm font-semibold text-gray-900 shadow-sm ring-1 ring-inset ring-gray-300 hover:bg-gray-50"
+          >
+            Comment
+          </button>
         </div>
-        <p class="text-sm leading-6 text-gray-500">
-          <%= @message.content %>
-        </p>
-      </div>
-    </li>
+      </.form>
+    </div>
     """
   end
 

lib/ex338_web/live/championship_live/show.ex

@@ -10,6 +10,7 @@ defmodule Ex338Web.ChampionshipLive.Show do
   alias Ex338.FantasyLeagues
   alias Ex338.InSeasonDraftPicks
   alias Ex338Web.ChampionshipLive.ChatComponent
+  alias Ex338Web.Presence
 
   @impl true
   def mount(_params, _session, socket) do
@@ -50,18 +51,38 @@ defmodule Ex338Web.ChampionshipLive.Show do
         Chats.subscribe(chat, socket.assigns.current_user)
       end
 
+      current_user = socket.assigns.current_user
+
+      if chat && current_user do
+        Presence.track(
+          self(),
+          Chats.topic(chat),
+          current_user.id,
+          default_user_presence_payload(current_user)
+        )
+      end
+
       socket
       |> assign(:chat, chat)
       |> assign(:message, %Message{})
       |> stream(:messages, chat.messages)
+      |> assign(:users, Presence.list_presences(Chats.topic(chat)))
     else
       _ ->
         socket
         |> assign(:chat, nil)
+        |> assign(:users, [])
         |> stream(:messages, [])
     end
   end
 
+  defp default_user_presence_payload(user) do
+    %{
+      name: user.name,
+      user_id: user.id
+    }
+  end
+
   @impl true
   def handle_info(:refresh, socket) do
     championship = Championships.update_next_in_season_pick(socket.assigns.championship)
@@ -112,6 +133,16 @@ defmodule Ex338Web.ChampionshipLive.Show do
     {:noreply, stream_insert(socket, :messages, message)}
   end
 
+  def handle_info(
+        %{event: "presence_diff", payload: _payload},
+        %{assigns: %{chat: chat}} = socket
+      ) do
+    users =
+      Presence.list_presences(Chats.topic(chat))
+
+    {:noreply, assign(socket, users: users)}
+  end
+
   # Implementations
 
   defp schedule_refresh do
@@ -312,14 +343,14 @@ defmodule Ex338Web.ChampionshipLive.Show do
           <.section_header>
             Draft Chat
           </.section_header>
-          <.live_component
-            module={ChatComponent}
-            id="chat"
+          <.chat_list
+            championship={@championship}
             chat={@chat}
+            current_user={@current_user}
+            fantasy_league={@fantasy_league}
             messages={@streams.messages}
             message={@message}
-            current_user={@current_user}
-            patch={~p"/fantasy_leagues/#{@fantasy_league.id}/championships/#{@championship.id}"}
+            users={@users}
           />
         </div>
       <% end %>
@@ -552,6 +583,106 @@ defmodule Ex338Web.ChampionshipLive.Show do
     """
   end
 
+  attr :chat, :map, required: true
+  attr :championship, :map, required: true
+  attr :current_user, :map, required: true
+  attr :fantasy_league, :map, required: true
+  attr :message, :map, required: true
+  attr :messages, :list, required: true
+  attr :users, :list, required: true
+
+  def chat_list(assigns) do
+    ~H"""
+    <div class="overflow-hidden bg-white shadow sm:rounded-lg">
+      <div class="py-5 border-b border-gray-200">
+        <ul
+          id="messages"
+          phx-update="stream"
+          role="list"
+          phx-hook="ChatScrollToBottom"
+          class="flex flex-col h-[800px] overflow-y-auto overflow-x-hidden pb-6"
+        >
+          <.comment :for={{id, message} <- @messages} id={id} message={message} />
+        </ul>
+
+        <.live_component
+          module={ChatComponent}
+          id="chat"
+          chat={@chat}
+          message={@message}
+          current_user={@current_user}
+          patch={~p"/fantasy_leagues/#{@fantasy_league.id}/championships/#{@championship.id}"}
+        />
+        <div class="mt-4 px-4 sm:px-6 ">
+          <h3>Online Users</h3>
+          <%= for user <- @users do %>
+            <p id={"online-user-#{user.user_id}"}>
+              <span class="inline-block h-2 w-2 flex-shrink-0 rounded-full bg-green-400">
+                <span class="sr-only">Online</span>
+              </span>
+              <span class="ml-1 text-xs leading-5 font-medium text-gray-900">
+                <%= user.name %>
+              </span>
+            </p>
+          <% end %>
+        </div>
+      </div>
+    </div>
+    """
+  end
+
+  defp comment(%{message: %{user: nil}} = assigns) do
+    ~H"""
+    <li id={@id} class="flex gap-x-4 hover:bg-gray-50 px-4 sm:px-6 py-2">
+      <div class="flex h-6 w-6 flex-none items-center justify-center">
+        <.icon name="hero-check-circle" class="h-6 w-6 text-indigo-600" />
+      </div>
+      <p class="flex-auto py-0.5 text-xs leading-5 text-gray-500">
+        <%= @message.content %>
+      </p>
+    </li>
+    """
+  end
+
+  defp comment(assigns) do
+    ~H"""
+    <li id={@id} class="flex gap-x-4 hover:bg-gray-50 px-4 sm:px-6 py-2">
+      <.user_icon name={@message.user.name} />
+      <div class="flex-auto">
+        <div class="flex justify-between items-start gap-x-4">
+          <div class="text-xs leading-5 font-medium text-gray-900">
+            <%= @message.user.name %>
+          </div>
+        </div>
+        <p class="text-sm leading-6 text-gray-500">
+          <%= @message.content %>
+        </p>
+      </div>
+    </li>
+    """
+  end
+
+  attr :name, :string, required: true
+  attr :class, :string, default: nil
+
+  defp user_icon(assigns) do
+    ~H"""
+    <div class={[
+      "h-6 w-6 flex flex-shrink-0 items-center justify-center bg-gray-600 rounded-full text-xs font-medium text-white",
+      @class
+    ]}>
+      <%= get_initials(@name) %>
+    </div>
+    """
+  end
+
+  defp get_initials(name) do
+    name
+    |> String.split(" ")
+    |> Enum.take(2)
+    |> Enum.map_join("", &String.at(&1, 0))
+  end
+
   defp get_team_name(%{fantasy_player: %{roster_positions: [position]}}) do
     position.fantasy_team.team_name
   end

lib/ex338_web/presence.ex

@@ -0,0 +1,16 @@
+defmodule Ex338Web.Presence do
+  @moduledoc false
+  use Phoenix.Presence,
+    otp_app: :ex338,
+    pubsub_server: Ex338.PubSub
+
+  alias Ex338Web.Presence
+
+  def list_presences(topic) do
+    topic
+    |> Presence.list()
+    |> Enum.map(fn {_user_id, data} ->
+      List.first(data[:metas])
+    end)
+  end
+end

test/ex338_web/live/championship_live/show_test.exs

@@ -322,6 +322,7 @@ defmodule Ex338Web.ChampionshipLive.ShowTest do
 
       assert has_element?(view, "h3", "Draft")
       assert has_element?(view, "p", "hello world!")
+      assert has_element?(view, "p#online-user-#{user.id}", user.name)
 
       long_comment = """
       In a quiet town nestled between rolling hills and dense forests, a small but spirited