From bafe5bae1cd0c7243ad1fb59709a45b2ba01ed15 Mon Sep 17 00:00:00 2001
From: DDDHuang <904897578@qq.com>
Date: Wed, 25 Aug 2021 11:29:13 +0800
Subject: [PATCH] fix: placeholder & topic schema no default

---
 .../emqx_auto_subscribe/src/emqx_auto_subscribe_placeholder.erl | 2 +-
 apps/emqx_auto_subscribe/src/emqx_auto_subscribe_schema.erl     | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_placeholder.erl b/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_placeholder.erl
index 72b2509cc..cbe881bde 100644
--- a/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_placeholder.erl
+++ b/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_placeholder.erl
@@ -61,7 +61,7 @@ to_topic([Binary | PTs], C, Co, Res) when is_binary(Binary) ->
 to_topic([clientid | PTs], C = #{clientid := ClientID}, Co, Res) ->
     to_topic(PTs, C, Co, [ClientID | Res]);
 to_topic([username | PTs], C = #{username := undefined}, Co, Res) ->
-    to_topic(PTs, C, Co, [<<"undefined">> | Res]);
+    to_topic(PTs, C, Co, [<<"${username}">> | Res]);
 to_topic([username | PTs], C = #{username := Username}, Co, Res) ->
     to_topic(PTs, C, Co, [Username | Res]);
 to_topic([host | PTs], C, Co = #{peername := {Host, _}}, Res) ->
diff --git a/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_schema.erl b/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_schema.erl
index 3a68b59ab..c3621f3a4 100644
--- a/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_schema.erl
+++ b/apps/emqx_auto_subscribe/src/emqx_auto_subscribe_schema.erl
@@ -29,6 +29,6 @@ fields("auto_subscribe") ->
     [ {topics, hoconsc:array(hoconsc:ref(?MODULE, "topic"))}];
 
 fields("topic") ->
-    [ {topic, emqx_schema:t(binary(), undefined, <<"">>)}
+    [ {topic, emqx_schema:t(binary())}
     , {qos, emqx_schema:t(integer(), undefined, 0)}
     ].