From a284ab9cf8f755b9d3acf30161aeff779bd46ddc Mon Sep 17 00:00:00 2001
From: DDDHuang <44492639+DDDHuang@users.noreply.github.com>
Date: Thu, 12 May 2022 11:06:07 +0800
Subject: [PATCH] fix: better error message for rule engine

---
 apps/emqx_rule_engine/src/emqx_rule_engine_api.erl | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/apps/emqx_rule_engine/src/emqx_rule_engine_api.erl b/apps/emqx_rule_engine/src/emqx_rule_engine_api.erl
index 7b843eb52..6f24ea50a 100644
--- a/apps/emqx_rule_engine/src/emqx_rule_engine_api.erl
+++ b/apps/emqx_rule_engine/src/emqx_rule_engine_api.erl
@@ -334,6 +334,11 @@ replace_sql_clrf(#{<<"sql">> := SQL} = Params) ->
 %% Internal functions
 %%------------------------------------------------------------------------------
 
+err_msg({_, [{validation_error, VMessage}]}) ->
+    Exp = maps:get(expected_data_type, VMessage),
+    Path = maps:get(path, VMessage),
+    ErrorArg = maps:get(got, VMessage),
+    list_to_binary(io_lib:format("Key ~p error, expect ~p , got ~p", [Path, Exp, ErrorArg]));
 err_msg(Msg) ->
     list_to_binary(io_lib:format("~0p", [Msg])).