support unicode in username, separate auth_request for scram and md5

lib/supavisor/client_handler.ex

@@ -404,8 +404,8 @@ defmodule Supavisor.ClientHandler do
         {user, nil}
 
       matches ->
-        {pos, _} = List.last(matches)
-        {name, "." <> external_id} = String.split_at(user, pos)
+        {pos, 1} = List.last(matches)
+        <<name::size(pos)-binary, ?., external_id::binary>> = user
         {name, external_id}
     end
   end
@@ -456,7 +456,7 @@ defmodule Supavisor.ClientHandler do
   @spec handle_exchange(S.sock(), {atom(), fun()}) :: {:ok, binary() | nil} | {:error, String.t()}
   def handle_exchange({_, socket} = sock, {:auth_query_md5 = method, secrets}) do
     salt = :crypto.strong_rand_bytes(4)
-    :ok = sock_send(sock, Server.auth_request(:md5, salt))
+    :ok = sock_send(sock, Server.md5_request(salt))
 
     with {:ok,
           %{
@@ -472,7 +472,7 @@ defmodule Supavisor.ClientHandler do
   end
 
   def handle_exchange({_, socket} = sock, {method, secrets}) do
-    :ok = sock_send(sock, Server.auth_request())
+    :ok = sock_send(sock, Server.scram_request())
 
     with {:ok,
           %{

lib/supavisor/protocol/server.ex

@@ -12,7 +12,7 @@ defmodule Supavisor.Protocol.Server do
   @authentication_ok <<?R, 8::32, 0::32>>
   @ready_for_query <<?Z, 5::32, ?I>>
   @ssl_request <<8::32, 1234::16, 5679::16>>
-  @auth_request <<?R, 23::32, 10::32, "SCRAM-SHA-256", 0, 0>>
+  @scram_request <<?R, 23::32, 10::32, "SCRAM-SHA-256", 0, 0>>
 
   defmodule Pkt do
     @moduledoc "Representing a packet structure with tag, length, and payload fields."
@@ -265,12 +265,14 @@ defmodule Supavisor.Protocol.Server do
     end
   end
 
-  @spec auth_request(:scram | :md5) :: iodata
-  def auth_request(method \\ :scram, salt \\ nil) do
-    case method do
-      :scram -> @auth_request
-      :md5 -> [<<?R, 12::32, 5::32>>, salt]
-    end
+  @spec scram_request() :: iodata
+  def scram_request() do
+    @scram_request
+  end
+
+  @spec md5_request(<<_::32>>) :: iodata
+  def md5_request(salt) do
+    [<<?R, 12::32, 5::32>>, salt]
   end
 
   @spec exchange_first_message(binary, binary | boolean, pos_integer) :: binary

test/supavisor/client_handler_test.exs

@@ -26,5 +26,12 @@ defmodule Supavisor.ClientHandlerTest do
       assert user1 == user
       assert external_id1 == external_id
     end
+
+    test "unicode in username" do
+      payload = %{"user" => "тестовe.імʼя.external_id"}
+      {name, external_id} = ClientHandler.parse_user_info(payload)
+      assert name == "тестовe.імʼя"
+      assert external_id == "external_id"
+    end
   end
 end