refactor(resman): rename `ets_lookup` → `lookup_cached`

That way we hide the impementation details + the interface becomes
cleaner and more obvious.

apps/emqx_resource/src/emqx_resource.erl

@@ -260,7 +260,7 @@ query(ResId, Request) ->
 -spec query(resource_id(), Request :: term(), query_opts()) ->
     Result :: term().
 query(ResId, Request, Opts) ->
-    case emqx_resource_manager:ets_lookup(ResId) of
+    case emqx_resource_manager:lookup_cached(ResId) of
         {ok, _Group, #{query_mode := QM, mod := Module}} ->
             IsBufferSupported = is_buffer_supported(Module),
             case {IsBufferSupported, QM} of
@@ -311,7 +311,7 @@ set_resource_status_connecting(ResId) ->
 -spec get_instance(resource_id()) ->
     {ok, resource_group(), resource_data()} | {error, Reason :: term()}.
 get_instance(ResId) ->
-    emqx_resource_manager:ets_lookup(ResId, [metrics]).
+    emqx_resource_manager:lookup_cached(ResId, [metrics]).
 
 -spec fetch_creation_opts(map()) -> creation_opts().
 fetch_creation_opts(Opts) ->

apps/emqx_resource/src/emqx_resource_buffer_worker.erl

@@ -885,7 +885,7 @@ handle_async_worker_down(Data0, Pid) ->
 
 call_query(QM0, Id, Index, Ref, Query, QueryOpts) ->
     ?tp(call_query_enter, #{id => Id, query => Query, query_mode => QM0}),
-    case emqx_resource_manager:ets_lookup(Id) of
+    case emqx_resource_manager:lookup_cached(Id) of
         {ok, _Group, #{status := stopped}} ->
             ?RESOURCE_ERROR(stopped, "resource stopped or disabled");
         {ok, _Group, Resource} ->

apps/emqx_resource/src/emqx_resource_manager.erl

@@ -36,8 +36,8 @@
     lookup/1,
     list_all/0,
     list_group/1,
-    ets_lookup/1,
-    ets_lookup/2,
+    lookup_cached/1,
+    lookup_cached/2,
     get_metrics/1,
     reset_metrics/1
 ]).
@@ -231,21 +231,21 @@ set_resource_status_connecting(ResId) ->
 -spec lookup(resource_id()) -> {ok, resource_group(), resource_data()} | {error, not_found}.
 lookup(ResId) ->
     case safe_call(ResId, lookup, ?T_LOOKUP) of
-        {error, timeout} -> ets_lookup(ResId, [metrics]);
+        {error, timeout} -> lookup_cached(ResId, [metrics]);
         Result -> Result
     end.
 
 %% @doc Lookup the group and data of a resource from the cache
--spec ets_lookup(resource_id()) -> {ok, resource_group(), resource_data()} | {error, not_found}.
-ets_lookup(ResId) ->
-    ets_lookup(ResId, []).
+-spec lookup_cached(resource_id()) -> {ok, resource_group(), resource_data()} | {error, not_found}.
+lookup_cached(ResId) ->
+    lookup_cached(ResId, []).
 
 %% @doc Lookup the group and data of a resource from the cache
--spec ets_lookup(resource_id(), [Option]) ->
+-spec lookup_cached(resource_id(), [Option]) ->
     {ok, resource_group(), resource_data()} | {error, not_found}
 when
     Option :: metrics.
-ets_lookup(ResId, Options) ->
+lookup_cached(ResId, Options) ->
     NeedMetrics = lists:member(metrics, Options),
     case read_cache(ResId) of
         {Group, Data} when NeedMetrics ->