fix: handle sync message when db_handler is busy (#355)

VERSION

@@ -1 +1 @@
-1.1.59
+1.1.60

lib/supavisor/client_handler.ex

@@ -422,6 +422,13 @@ defmodule Supavisor.ClientHandler do
     {:keep_state_and_data, handle_actions(data)}
   end
 
+  def handle_event(:info, {proto, _, <<?S, 4::32>> = msg}, _, data)
+      when proto in [:tcp, :ssl] do
+    Logger.debug("ClientHandler: Receive sync while not idle")
+    Db.cast(data.db_pid, self(), msg)
+    :keep_state_and_data
+  end
+
   # incoming query with a single pool
   def handle_event(:info, {proto, _, bin}, :idle, %{pool: pid} = data)
       when is_binary(bin) and is_pid(pid) do

lib/supavisor/db_handler.ex

@@ -28,6 +28,9 @@ defmodule Supavisor.DbHandler do
   @spec call(pid(), pid(), binary()) :: :ok | {:error, any()} | {:buffering, non_neg_integer()}
   def call(pid, caller, msg), do: :partisan_gen_statem.call(pid, {:db_call, caller, msg}, 15_000)
 
+  @spec cast(pid(), pid(), binary()) :: :ok | {:error, any()} | {:buffering, non_neg_integer()}
+  def cast(pid, caller, msg), do: :partisan_gen_statem.cast(pid, {:db_cast, caller, msg})
+
   @spec get_state_and_mode(pid()) :: {:ok, {state, Supavisor.mode()}} | {:error, term()}
   def get_state_and_mode(pid) do
     try do
@@ -408,6 +411,16 @@ defmodule Supavisor.DbHandler do
     {:keep_state, %{data | caller: caller, buffer: new_buff}, reply}
   end
 
+  # emulate handle_cast
+  def handle_event(:cast, {:db_cast, caller, bin}, state, %{sock: sock}) do
+    Logger.debug(
+      "DbHandler: state #{state} <-- <-- bin #{inspect(byte_size(bin))} bytes, cast caller: #{inspect(caller)}"
+    )
+
+    sock_send(sock, bin)
+    :keep_state_and_data
+  end
+
   def handle_event(_, {closed, _}, :busy, data) when closed in @sock_closed do
     {:stop, :db_termination, data}
   end