sockets - 广播到不同 channel Phoenix 1.1.6

Question

我试图在我的应用程序中广播到不同的 channel ，但我无法让它工作。我也想写一个测试，但我不确定如何。

据我所知，我成功地从 notification_channel 广播了消息，但没有在 chat_channel 中收到。

通知应发送到聊天。

notification_channel.ex

  def handle_in("new:group:recommendation", msg, socket) do
    payload = %{
        message: msg["message"],
        url: msg["url"],
        title: msg["title"],
        user_name: get_name_of_user(socket.assigns.user_grapqhl_id),
        user_grapqhl_id: socket.assigns.user_grapqhl_id
    }

    IO.puts "incomming"
    IO.inspect msg
    Enum.map(msg["groups"], fn(x) ->
        App.Endpoint.broadcast_from! self(), "chat:"<>x,
            "new:recommendation", payload
        end)
    {:reply, :ok, socket}

  end

chat_channel.ex

 def handle_in("new:recommendation", msg, socket) do
      IO.puts "i am a recommendation !"
      IO.inspect msg
      chat_msg = %{
         "creator_id" => msg["user_grapqhl_id"],
         "text" => msg["message"],
         "creator_name" => msg["user_name"]
      }

     broadcast! socket, "new:msg", create_chat_msg(chat_msg,socket)
     {:reply, :ok, socket}
  end

测试

  test "do we send a new:recommendation to chat ?", %{guardian_token: guardian_token} do
      nils_base_64 = Base.encode64("user:nils")

      {:ok, socket} = connect(UserSocket, %{})
      {:ok, _, socket1} = subscribe_and_join(socket, "notifications:"<>nils_base_64, %{"guardian_token" => guardian_token})
      {:ok, _, socket} = subscribe_and_join(socket1, "chat:Y2hhdDpjaGF0Mw==", %{"guardian_token" => guardian_token})

      payload = %{
          "message" => "look at this cool thing!",
          "url" => "link to stuff",
          "title" => "AWESOME EVENT",
          "groups" => ["Y2hhdDpjaGF0Mw==", "Y2hhdDpwdWJsaWM="]
      }

      reply = %{message: "look at this cool thing!", title: "AWESOME EVENT", url: "link to stuff", user_grapqhl_id: nils_base_64, user_name: "Nils Eriksson"}

      ref = push socket1, "new:group:recommendation", payload
      assert_reply ref, :ok
      assert_broadcast "new:recommendation", ^reply
  end

此测试通过，我可以通过更改 reply 使其失败
或评论广播。我无法通过更改 handle_in 使其失败接收 fail:please在 chat_channel .
如果我发送更改此内容，它会提示这一点ref = push socket1, "new:group:recommendation", payload至 ref = push socket, "new:group:recommendation", payload在这种情况下并不奇怪。

这是电线上的东西。

     Process mailbox:
   %Phoenix.Socket.Message{event: "init:msgs", payload: %{messages: []}, ref: nil, topic: "chat:Y2hhdDpjaGF0Mw=="}
   %Phoenix.Socket.Broadcast{event: "new:recommendation", payload: %{message: "look at this cool thing!", title: "AWESOME EVENTs", url: "link to stuff", user_grapqhl_id: "dXNlcjpuaWxz", user_name: "Nils Eriksson"}, topic: "chat:Y2hhdDpjaGF0Mw=="}
   %Phoenix.Socket.Message{event: "new:recommendation", payload: %{message: "look at this cool thing!", title: "AWESOME EVENTs", url: "link to stuff", user_grapqhl_id: "dXNlcjpuaWxz", user_name: "Nils Eriksson"}, ref: nil, topic: "chat:Y2hhdDpjaGF0Mw=="}

我使用 channel 身份验证，因为我使用的 elm 包不支持套接字级别的身份验证。所以这就是 chat 中的样子

  def join("chat:" <> chat_id, %{"guardian_token" => token}, socket) do
  IO.puts chat_id
  case sign_in(socket, token) do
     {:ok, authed_socket, _guardian_params} ->
         Process.flag(:trap_exit, true)
         send(self, {:after_join})
         [_type, node_chat_id] = Node.from_global_id(chat_id)
         {:ok, assign(authed_socket, :chat_id, node_chat_id)}
     {:error, reason} ->
         IO.puts "Can't join channel cuz: " <> reason
       # handle error TODO
   end

结尾

Answer 1

由于您使用 broadcast_from/4来自您的 Endpoint .你应该使用 handle_info/2在您的 chat_channel :

alias Phoenix.Socket.Broadcast
  ...

def handle_info(%Broadcast{topic: _, event: ev, payload: payload}, socket) do
    IO.puts ev
    IO.inspect payload
    # do something with ev and payload( push or broadcast)
    {:noreply, socket}
  end

或者您可以从客户端收听该事件:

chatChannel.on("new:recommendation", resp => {
   // doSomething with response
}

编辑:

让我们解释一下 channel和 PubSub系统工作。

当你想广播或推送一个带有有效载荷的事件时。首先它会发送到 PubSub系统，然后是 PubSub系统会将其发送给所有订阅者进程( channel )，主题为 channel在 PubSub 注册自己系统。

当您使用 Endpoint.broadcast_from/4 时从您的服务器广播事件。PubSub系统将接收一个带有有效负载的事件并将该事件广播到该 channel 注册的主题。

channel 会触发handle_out回调并将消息推送到客户端。
所以在您的 chat_channel你不需要handle_in "new:recommendation"事件。您的客户只需要收听该事件。

chatChannel.on("new:recommendation", resp => {
   // do something with response
}

让我重写你的测试:

setup do
    nils_base_64 = Base.encode64("user:nils")
    {:ok, socket} = connect(UserSocket, %{})
    {:ok, _, socket} = subscribe_and_join(socket, "notifications:"<>nils_base_64, %{"guardian_token" => guardian_token})
    {:ok, socket: socket}
  end


test "do we send a new:recommendation to chat ?", %{socket: socket} do
      MyApp.Endpoint.subscribe("chat:Y2hhdDpjaGF0Mw==")

      payload = %{
          "message" => "look at this cool thing!",
          "url" => "link to stuff",
          "title" => "AWESOME EVENT",
          "groups" => ["Y2hhdDpjaGF0Mw==", "Y2hhdDpwdWJsaWM="]
      }



      reply = %Phoenix.Socket.Broadcast{message: "look at this cool thing!",
              title: "AWESOME EVENT",
              url: "link to stuff",
              user_grapqhl_id: nils_base_64,
              user_name: "Nils Eriksson"}

      ref = push socket, "new:group:recommendation", payload
      assert_reply ref, :ok
      assert_receive ^reply
  end

来自 subscribe对于您想收听的主题，您可以确保您的 channel 收到了带有 assert_receive 的消息。 .
那就是测试broadcast的方法到不同的 channel 。

试一试告诉我，测试会通过的。