From e8e956b074745c094c5d203d33382186e41a80da Mon Sep 17 00:00:00 2001
From: k32 <10274441+k32@users.noreply.github.com>
Date: Mon, 28 Jun 2021 21:02:26 +0200
Subject: [PATCH 1/2] chore(mod_delayed): Add RLOG shard

---
 apps/emqx/include/emqx.hrl                 | 1 +
 apps/emqx/src/emqx_app.erl                 | 1 +
 apps/emqx_modules/src/emqx_mod_delayed.erl | 7 ++++---
 3 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/apps/emqx/include/emqx.hrl b/apps/emqx/include/emqx.hrl
index 67744306e..d148e01a3 100644
--- a/apps/emqx/include/emqx.hrl
+++ b/apps/emqx/include/emqx.hrl
@@ -25,6 +25,7 @@
 
 -define(COMMON_SHARD, emqx_common_shard).
 -define(SHARED_SUB_SHARD, emqx_shared_sub_shard).
+-define(MOD_DELAYED_SHARD, emqx_delayed_shard).
 
 %%--------------------------------------------------------------------
 %% Banner
diff --git a/apps/emqx/src/emqx_app.erl b/apps/emqx/src/emqx_app.erl
index 06bebe465..60f0fc40d 100644
--- a/apps/emqx/src/emqx_app.erl
+++ b/apps/emqx/src/emqx_app.erl
@@ -32,6 +32,7 @@
                      , ?COMMON_SHARD
                      , ?SHARED_SUB_SHARD
                      , ?RULE_ENGINE_SHARD
+                     , ?MOD_DELAYED_SHARD
                      ]).
 
 -include("emqx_release.hrl").
diff --git a/apps/emqx_modules/src/emqx_mod_delayed.erl b/apps/emqx_modules/src/emqx_mod_delayed.erl
index ac5be58b2..925952078 100644
--- a/apps/emqx_modules/src/emqx_mod_delayed.erl
+++ b/apps/emqx_modules/src/emqx_mod_delayed.erl
@@ -58,6 +58,8 @@
 -define(SERVER, ?MODULE).
 -define(MAX_INTERVAL, 4294967).
 
+-rlog_shard({?MOD_DELAYED_SHARD, ?TAB}).
+
 %%--------------------------------------------------------------------
 %% Mnesia bootstrap
 %%--------------------------------------------------------------------
@@ -137,7 +139,7 @@ init([]) ->
            ensure_publish_timer(#{timer => undefined, publish_at => 0}))}.
 
 handle_call({store, DelayedMsg = #delayed_message{key = Key}}, _From, State) ->
-    ok = mnesia:dirty_write(?TAB, DelayedMsg),
+    ok = ekka_mnesia:dirty_write(?TAB, DelayedMsg),
     emqx_metrics:inc('messages.delayed'),
     {reply, ok, ensure_publish_timer(Key, State)};
 
@@ -152,7 +154,7 @@ handle_cast(Msg, State) ->
 %% Do Publish...
 handle_info({timeout, TRef, do_publish}, State = #{timer := TRef}) ->
     DeletedKeys = do_publish(mnesia:dirty_first(?TAB), os:system_time(seconds)),
-    lists:foreach(fun(Key) -> mnesia:dirty_delete(?TAB, Key) end, DeletedKeys),
+    lists:foreach(fun(Key) -> ekka_mnesia:dirty_delete(?TAB, Key) end, DeletedKeys),
     {noreply, ensure_publish_timer(State#{timer := undefined, publish_at := 0})};
 
 handle_info(stats, State = #{stats_fun := StatsFun}) ->
@@ -222,4 +224,3 @@ do_publish(Key = {Ts, _Id}, Now, Acc) when Ts =< Now ->
 
 -spec(delayed_count() -> non_neg_integer()).
 delayed_count() -> mnesia:table_info(?TAB, size).
-

From cc5bc4f7ca3e831210d37dde3b3befd2ae013f24 Mon Sep 17 00:00:00 2001
From: k32 <10274441+k32@users.noreply.github.com>
Date: Tue, 29 Jun 2021 00:27:53 +0200
Subject: [PATCH 2/2] build(rlog): Add xref check for forbidden mnesia APIs

---
 rebar.config | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/rebar.config b/rebar.config
index 205d892aa..e5f46125a 100644
--- a/rebar.config
+++ b/rebar.config
@@ -15,6 +15,15 @@
 {xref_checks,[undefined_function_calls,undefined_functions,locals_not_used,
               deprecated_function_calls,warnings_as_errors,deprecated_functions]}.
 
+%% Check for the mnesia calls forbidden by Ekka:
+{xref_queries,
+ [ {"E || \"mnesia\":\"dirty_write\"/\".*\" : Fun", []}
+ , {"E || \"mnesia\":\"dirty_delete.*\"/\".*\" : Fun", []}
+ , {"E || \"mnesia\":\"transaction\"/\".*\" : Fun", []}
+ , {"E || \"mnesia\":\"async_dirty\"/\".*\" : Fun", []}
+ , {"E || \"mnesia\":\"clear_table\"/\".*\" : Fun", []}
+ ]}.
+
 {dialyzer, [
     {warnings, [unmatched_returns, error_handling, race_conditions]},
     {plt_location, "."},