# Pleroma: A lightweight social networking server # Copyright © 2017-2021 Pleroma Authors <https://pleroma.social/> # SPDX-License-Identifier: AGPL-3.0-only defmodule Pleroma.Web.ShoutChannel do use Phoenix.Channel alias Pleroma.User alias Pleroma.Web.MastodonAPI.AccountView alias Pleroma.Web.ShoutChannel.ShoutChannelState def join("chat:public", _message, socket) do send(self(), :after_join) {:ok, socket} end def handle_info(:after_join, socket) do push(socket, "messages", %{messages: ShoutChannelState.messages()}) {:noreply, socket} end def handle_in("new_msg", %{"text" => text}, %{assigns: %{user_name: user_name}} = socket) do text = String.trim(text) if String.length(text) in 1..Pleroma.Config.get([:shout, :limit]) do author = User.get_cached_by_nickname(user_name) author_json = AccountView.render("show.json", user: author, skip_visibility_check: true) message = ShoutChannelState.add_message(%{text: text, author: author_json}) broadcast!(socket, "new_msg", message) end {:noreply, socket} end end defmodule Pleroma.Web.ShoutChannel.ShoutChannelState do use Agent @max_messages 20 def start_link(_) do Agent.start_link(fn -> %{max_id: 1, messages: []} end, name: __MODULE__) end def add_message(message) do Agent.get_and_update(__MODULE__, fn state -> id = state[:max_id] + 1 message = Map.put(message, "id", id) messages = [message | state[:messages]] |> Enum.take(@max_messages) {message, %{max_id: id, messages: messages}} end) end def messages do Agent.get(__MODULE__, fn state -> state[:messages] |> Enum.reverse() end) end end