refactor(emqx_license): log a different msg when license is not loaded

lib-ee/emqx_license/include/emqx_license.hrl

@@ -35,4 +35,5 @@
 
 -define(EXPIRED_DAY, -90).
 
+-define(ERR_EXPIRED, expired).
 -endif.

lib-ee/emqx_license/src/emqx_license.erl

@@ -3,6 +3,7 @@
 %%--------------------------------------------------------------------
 -module(emqx_license).
 
+-include("emqx_license.hrl").
 -include_lib("emqx/include/logger.hrl").
 -include_lib("emqx/include/emqx_mqtt.hrl").
 -include_lib("typerefl/include/types.hrl").
@@ -67,19 +68,22 @@ update_key(Value) when is_binary(Value); is_list(Value) ->
 %%------------------------------------------------------------------------------
 
 check(_ConnInfo, AckProps) ->
-    #{max_connections := MaxClients} = emqx_license_checker:limits(),
-    case MaxClients of
-        0 ->
-            ?SLOG(error, #{msg => "Connection rejected due to the license expiration"}),
+    case emqx_license_checker:limits() of
+        {ok, #{max_connections := ?ERR_EXPIRED}} ->
+            ?SLOG(error, #{msg => "connection_rejected_due_to_license_expired"}),
             {stop, {error, ?RC_QUOTA_EXCEEDED}};
-        _ ->
+        {ok, #{max_connections := MaxClients}} ->
             case check_max_clients_exceeded(MaxClients) of
                 true ->
-                    ?SLOG(error, #{msg => "Connection rejected due to max clients limitation"}),
+                    ?SLOG(error, #{msg => "connection_rejected_due_to_license_limit_reached"}),
                     {stop, {error, ?RC_QUOTA_EXCEEDED}};
                 false ->
                     {ok, AckProps}
-            end
+            end;
+        {error, Reason} ->
+            ?SLOG(error, #{msg => "connection_rejected_due_to_license_not_loaded",
+                           reason => Reason}),
+            {stop, {error, ?RC_QUOTA_EXCEEDED}}
     end.
 
 %%------------------------------------------------------------------------------

lib-ee/emqx_license/src/emqx_license_checker.erl

@@ -27,7 +27,7 @@
 %% API
 %%------------------------------------------------------------------------------
 
--type limits() :: #{max_connections := non_neg_integer()}.
+-type limits() :: #{max_connections := non_neg_integer() | ?ERR_EXPIRED}.
 
 -spec start_link(emqx_license_parser:license()) -> {ok, pid()}.
 start_link(LicenseFetcher) ->
@@ -45,13 +45,14 @@ update(License) ->
 dump() ->
     gen_server:call(?MODULE, dump).
 
--spec limits() -> limits().
+-spec limits() -> {ok, limits()} | {error, any()}.
 limits() ->
     try ets:lookup(?MODULE, limits) of
-        [{limits, Limits}] -> Limits;
-        _ -> default_limits()
+        [{limits, Limits}] -> {ok, Limits};
+        _ -> {error, no_license}
     catch
-        error:badarg -> default_limits()
+        error : badarg ->
+            {error, no_license}
     end.
 
 %%------------------------------------------------------------------------------
@@ -116,9 +117,7 @@ warn_evaluation(_License, _NeedRestrict) -> false.
 warn_expiry(_License, NeedRestrict) -> NeedRestrict.
 
 limits(License, false) -> #{max_connections => emqx_license_parser:max_connections(License)};
-limits(_License, true) -> #{max_connections => 0}.
-
-default_limits() -> #{max_connections => 0}.
+limits(_License, true) -> #{max_connections => ?ERR_EXPIRED}.
 
 days_left(License) ->
     DateEnd = emqx_license_parser:expiry_date(License),

lib-ee/emqx_license/test/emqx_license_checker_SUITE.erl

@@ -47,7 +47,7 @@ set_special_configs(_) -> ok.
 %%------------------------------------------------------------------------------
 
 t_default_limits(_Config) ->
-    ?assertMatch(#{max_connections := 0}, emqx_license_checker:limits()).
+    ?assertMatch({error, no_license}, emqx_license_checker:limits()).
 
 t_dump(_Config) ->
     License = mk_license(
@@ -86,7 +86,7 @@ t_update(_Config) ->
     #{} = emqx_license_checker:update(License),
 
     ?assertMatch(
-       #{max_connections := 123},
+       {ok, #{max_connections := 123}},
        emqx_license_checker:limits()).
 
 t_update_by_timer(_Config) ->
@@ -122,7 +122,7 @@ t_expired_trial(_Config) ->
     #{} = emqx_license_checker:update(License),
 
     ?assertMatch(
-       #{max_connections := 0},
+       {ok, #{max_connections := expired}},
        emqx_license_checker:limits()).
 
 t_overexpired_small_client(_Config) ->
@@ -142,7 +142,7 @@ t_overexpired_small_client(_Config) ->
     #{} = emqx_license_checker:update(License),
 
     ?assertMatch(
-       #{max_connections := 0},
+       {ok, #{max_connections := expired}},
        emqx_license_checker:limits()).
 
 t_overexpired_medium_client(_Config) ->
@@ -162,7 +162,7 @@ t_overexpired_medium_client(_Config) ->
     #{} = emqx_license_checker:update(License),
 
     ?assertMatch(
-       #{max_connections := 123},
+       {ok, #{max_connections := 123}},
        emqx_license_checker:limits()).
 
 t_recently_expired_small_client(_Config) ->
@@ -182,7 +182,7 @@ t_recently_expired_small_client(_Config) ->
     #{} = emqx_license_checker:update(License),
 
     ?assertMatch(
-       #{max_connections := 123},
+       {ok, #{max_connections := 123}},
        emqx_license_checker:limits()).
 
 t_unknown_calls(_Config) ->