Remove check for MQTT path, and normalize code

etc/emqx.conf

@@ -1207,7 +1207,7 @@ listener.ssl.external.reuseaddr = true
 ## Examples: 8083, 127.0.0.1:8083, ::1:8083
 listener.ws.external = 8083
 
-## Define the path you want to add to the end of the URL 
+## The path of WebSocket MQTT endpoint
 ##
 ## Value: / | /<Any String>
 listener.ws.external.mqtt_path = /mqtt
@@ -1351,7 +1351,7 @@ listener.ws.external.nodelay = true
 ## Examples: 8084, 127.0.0.1:8084, ::1:8084
 listener.wss.external = 8084
 
-## Define the path you want to add to the end of the URL 
+## The path of WebSocket MQTT endpoint
 ##
 ## Value: / | /<Any String>
 listener.wss.external.mqtt_path = /mqtt

priv/emqx.schema

@@ -1375,8 +1375,8 @@ end}.
                 end,
 
     LisOpts = fun(Prefix) ->
-                  Filter([{mqtt_path, cuttlefish:conf_get(Prefix ++ ".mqtt_path", Conf, undefined)},
-                          {acceptors, cuttlefish:conf_get(Prefix ++ ".acceptors", Conf)},
+                  Filter([{acceptors, cuttlefish:conf_get(Prefix ++ ".acceptors", Conf)},
+                          {mqtt_path, cuttlefish:conf_get(Prefix ++ ".mqtt_path", Conf, undefined)},
                           {max_connections, cuttlefish:conf_get(Prefix ++ ".max_connections", Conf)},
                           {max_conn_rate, cuttlefish:conf_get(Prefix ++ ".max_conn_rate", Conf, undefined)},
                           {tune_buffer, cuttlefish:conf_get(Prefix ++ ".tune_buffer", Conf, undefined)},

src/emqx_listeners.erl

@@ -22,12 +22,6 @@
 -export([restart_listener/1, restart_listener/3]).
 -export([stop_listener/1, stop_listener/3]).
 
--ifdef(TEST).
-
--export([mqtt_path/1]).
-
--endif.
-
 -type(listener() :: {esockd:proto(), esockd:listen_on(), [esockd:option()]}).
 
 %% @doc Start all listeners.
@@ -74,12 +68,7 @@ start_http_listener(Start, Name, ListenOn, RanchOpts, Dispatch) ->
     Start(Name, with_port(ListenOn, RanchOpts), #{env => #{dispatch => Dispatch}}).
 
 mqtt_path(Options) ->
-    MQTTPath = proplists:get_value(mqtt_path, Options, "/mqtt"),
-    case erlang:list_to_bitstring(MQTTPath) of
-        <<"/">> -> MQTTPath;
-        <<"/", _/binary>> -> MQTTPath;
-        _ -> "/mqtt"
-    end.
+    proplists:get_value(mqtt_path, Options, "/mqtt").
 
 ranch_opts(Options) ->
     NumAcceptors = proplists:get_value(acceptors, Options, 4),

src/emqx_protocol.erl

@@ -249,13 +249,6 @@ preprocess_properties(Packet = #mqtt_packet{
                       PState = #pstate{proto_ver = ?MQTT_PROTO_V5, topic_aliases = Aliases}) ->
     {Packet, PState#pstate{topic_aliases = maps:put(AliasId, Topic, Aliases)}};
 
-preprocess_properties(Packet = #mqtt_packet{variable = #mqtt_packet_publish{properties = #{'Message-Expiry-Interval' := _Interval}}},
-                      PState = #pstate{proto_ver = ?MQTT_PROTO_V5}) ->
-    {Packet, PState};
-preprocess_properties(Packet = #mqtt_packet{variable = Publish = #mqtt_packet_publish{properties = Properties}},
-                      PState = #pstate{proto_ver = ?MQTT_PROTO_V5}) ->
-    {Packet#mqtt_packet{variable = Publish#mqtt_packet_publish{properties = maps:put('Message-Expiry-Interval', 0, Properties)}}, PState};
-
 preprocess_properties(Packet, PState) ->
     {Packet, PState}.
 

test/emqx_listeners_SUITE.erl

@@ -26,8 +26,7 @@
 
 all() ->
     [start_stop_listeners,
-     restart_listeners,
-     t_mqtt_path].
+     restart_listeners].
 
 init_per_suite(Config) ->
     NewConfig = generate_config(),
@@ -50,11 +49,6 @@ restart_listeners(_) ->
     ok = emqx_listeners:restart(),
     ok = emqx_listeners:stop().
 
-t_mqtt_path(_) ->
-    ?assertEqual("/test", emqx_listeners:mqtt_path([{mqtt_path, "/test"}])),
-    ?assertEqual("/", emqx_listeners:mqtt_path([{mqtt_path, "/"}])),
-    ?assertEqual("/mqtt", emqx_listeners:mqtt_path([{mqtt_path, "test"}])).
-
 generate_config() ->
     Schema = cuttlefish_schema:files([local_path(["priv", "emqx.schema"])]),
     Conf = conf_parse:file([local_path(["etc", "gen.emqx.conf"])]),