Re-activate clients if they are restarted

lib/chronoscope/nts.ex

@@ -25,12 +25,16 @@ defmodule Chronoscope.NTS do
     |> Enum.map(fn {_, pid, _, _} -> @genserver.call(pid, :list) end)
   end
 
-  def list_clients(clients) do
-    clients
+  def list_clients(servers) do
+    servers
     |> Enum.map(&client_pid/1)
     |> Enum.map(fn pid -> @genserver.call(pid, :list, @timeout_in_milliseconds) end)
   end
 
+  def start_client(server) do
+    client_pid(server)
+  end
+
   def auto_refresh(server) do
     server
     |> client_pid()

lib/chronoscope/nts/client.ex

@@ -3,6 +3,7 @@ defmodule Chronoscope.NTS.Client do
 
   alias Chronoscope.NTS
   alias Chronoscope.NTS.KeyEstablishmentClient
+  alias ChronoscopeWeb.Endpoint
 
   @interval_in_seconds 30
   @timeout_in_milliseconds 10_000
@@ -17,13 +18,13 @@ defmodule Chronoscope.NTS.Client do
 
   @impl true
   def init(server) do
-    now = utc_now()
+    Endpoint.broadcast(@topic, "initializing", server)
 
     {:ok,
      %{
        server: server,
        key_establishment_response: {:error, "initializing"},
-       last_key_establishment: DateTime.add(now, -@interval_in_seconds, :second)
+       last_key_establishment: DateTime.add(utc_now(), -@interval_in_seconds, :second)
      }}
   end
 
@@ -53,6 +54,8 @@ defmodule Chronoscope.NTS.Client do
   @impl true
   def handle_call(:cancel_auto_refresh, _from, %{timer: timer} = state) do
     :timer.cancel(timer)
+    Endpoint.broadcast(@topic, "cancel-auto-refresh", state.server)
+
     {:reply, :ok, Map.delete(state, :timer)}
   end
 
@@ -79,7 +82,7 @@ defmodule Chronoscope.NTS.Client do
     if interval_surpassed?(now, state.last_key_establishment) do
       state
       |> Map.merge(current_data(state, now))
-      |> tap(&ChronoscopeWeb.Endpoint.broadcast(@topic, "key-exchange", Map.delete(&1, :timer)))
+      |> tap(&Endpoint.broadcast(@topic, "key-exchange", Map.delete(&1, :timer)))
     else
       state
     end

lib/chronoscope_web/client_activator.ex

@@ -5,9 +5,9 @@ defmodule ChronoscopeWeb.ClientActivator do
 
   alias Chronoscope.NTS
   alias Chronoscope.NTS.Parse
+  alias ChronoscopeWeb.Endpoint
 
-  @activate_interval_in_milliseconds 300_000
-
+  @topic Application.compile_env(:chronoscope, :nts_topic)
   @nts_file Application.compile_env(:chronoscope, :nts_file)
 
   def start_link(_) do
@@ -16,29 +16,33 @@ defmodule ChronoscopeWeb.ClientActivator do
 
   @impl true
   def init(_) do
-    nts_servers =
-      nts_servers()
-      |> tap(fn servers -> Enum.each(servers, &NTS.auto_refresh/1) end)
+    Endpoint.subscribe(@topic)
 
-    :timer.send_interval(@activate_interval_in_milliseconds, :ensure_activated)
-
-    {:ok, %{nts_servers: nts_servers}}
+    {:ok, %{nts_servers: nts_servers() |> tap(&start_clients/1)}}
   end
 
   @impl true
-  def handle_info(:ensure_activated, state) do
-    Enum.each(state.nts_servers, &NTS.auto_refresh/1)
+  def handle_info(%{topic: @topic, event: "initializing", payload: server}, state) do
+    if server in state.nts_servers do
+      Logger.info("activating #{inspect(server)}")
+      NTS.auto_refresh(server)
+    end
 
     {:noreply, state}
   end
 
   @impl true
-  def handle_info(:activate_clients, _state) do
-    nts_servers =
-      nts_servers()
-      |> tap(fn servers -> Enum.each(servers, &NTS.auto_refresh/1) end)
+  def handle_info(%{topic: @topic, event: "cancel-auto-refresh", payload: server}, state) do
+    if server in state.nts_servers do
+      Logger.info("#{inspect(server)} was deactivated")
+    end
 
-    {:noreply, %{nts_servers: nts_servers}}
+    {:noreply, state}
+  end
+
+  @impl true
+  def handle_info(_, state) do
+    {:noreply, state}
   end
 
   @impl true
@@ -46,6 +50,10 @@ defmodule ChronoscopeWeb.ClientActivator do
     {:reply, state.nts_servers, state}
   end
 
+  defp start_clients(servers) do
+    Enum.each(servers, &NTS.start_client/1)
+  end
+
   defp nts_servers() do
     File.touch(Application.app_dir(:chronoscope, @nts_file))
 

lib/chronoscope_web/live/index_live.ex

@@ -4,14 +4,17 @@ defmodule ChronoscopeWeb.IndexLive do
   alias Chronoscope.NTS
   alias Chronoscope.NTS.KeyEstablishmentResponse
   alias ChronoscopeWeb.ClientActivator
+  alias ChronoscopeWeb.Endpoint
 
   @topic Application.compile_env(:chronoscope, :nts_topic)
 
+  @impl true
   def mount(_params, _session, socket) do
-    ChronoscopeWeb.Endpoint.subscribe(@topic)
+    Endpoint.subscribe(@topic)
     {:ok, assign(socket, %{servers: server_list(), clients: client_list()})}
   end
 
+  @impl true
   def handle_info(%{topic: @topic, event: "key-exchange", payload: client}, socket) do
     if client.server in socket.assigns.servers do
       {:noreply, update(socket, :clients, &update_client(&1, client))}
@@ -20,6 +23,11 @@ defmodule ChronoscopeWeb.IndexLive do
     end
   end
 
+  @impl true
+  def handle_info(_, socket) do
+    {:noreply, socket}
+  end
+
   defp update_client(client_list, client) do
     Enum.map(client_list, &if(client.server == &1.server, do: client, else: &1))
   end
@@ -29,7 +37,6 @@ defmodule ChronoscopeWeb.IndexLive do
   end
 
   defp client_list() do
-    server_list()
-    |> NTS.list_clients()
+    server_list() |> NTS.list_clients()
   end
 end

priv/nts.txt

@@ -5,3 +5,5 @@ paris.time.system76.com
 oregon.time.system76.com
 ohio.time.system76.com
 brazil.time.system76.com
+time.cloudflare.com
+nts.netnod.se