From 74a82f9374bbfeb377f143cca19af6b22ecb42ab Mon Sep 17 00:00:00 2001
From: ieQu1 <99872536+ieQu1@users.noreply.github.com>
Date: Fri, 30 Jun 2023 13:11:44 +0200
Subject: [PATCH] fix(cluster): Don't generate random node names

---
 src/conf/emqttb_conf_model.erl |  6 +++---
 src/framework/emqttb_app.erl   | 18 ++++++++++--------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/src/conf/emqttb_conf_model.erl b/src/conf/emqttb_conf_model.erl
index 3313089..f598ea7 100644
--- a/src/conf/emqttb_conf_model.erl
+++ b/src/conf/emqttb_conf_model.erl
@@ -41,11 +41,11 @@ model() ->
          , prog_name   => "emqttb"
          }}
    , cluster =>
-       #{ enabled =>
+       #{ node_name =>
             {[value, os_env],
              #{ oneliner => "Enable clustering"
-              , type     => boolean()
-              , default  => true
+              , type     => atom()
+              , default  => undefined
               }}
         }
    , interval          =>
diff --git a/src/framework/emqttb_app.erl b/src/framework/emqttb_app.erl
index abe4b71..588cc3f 100644
--- a/src/framework/emqttb_app.erl
+++ b/src/framework/emqttb_app.erl
@@ -37,13 +37,15 @@ post_init() ->
                                 , {emqttb_pushgw, start_link, []}
                                 ),
   emqttb_logger:setup(),
-  ?CFG([cluster, enabled]) andalso
-    start_distr(),
+  maybe_start_distr(),
   ok.
 
-start_distr() ->
-  os:cmd("epmd -daemon"),
-  Opts = #{dist_listen => true, name_domain => shortnames},
-  Name = list_to_atom("emqttb-" ++ [$A + rand:uniform($Z-$A) - 1 || _ <- lists:seq(1, 5)]),
-  net_kernel:start(Name, Opts),
-  logger:notice("Started distribution with name: ~p", [node()]).
+maybe_start_distr() ->
+  case ?CFG([cluster, node_name]) of
+    undefined ->
+      ok;
+    Name ->
+      os:cmd("epmd -daemon"),
+      Opts = #{dist_listen => true, name_domain => shortnames},
+      net_kernel:start(Name, Opts)
+  end.