fix mneisa

apps/iot/src/iot_app.erl

@@ -13,14 +13,8 @@ start(_StartType, _StartArgs) ->
     io:setopts([{encoding, unicode}]),
     %% 加速内存的回收
     erlang:system_flag(fullsweep_after, 16),
-    try
-        %% 启动并校验已经初始化好的 mnesia 数据库
-        ok = iot_mnesia:start()
-    catch
-        Class:Reason:Stack ->
-            logger:warning("[iot_app] start failed, class: ~p, reason: ~p, stack: ~p", [Class, Reason, Stack]),
-            ok = iot_mnesia:init()
-    end,
+
+    iot_mnesia:safe_start(),
 
     %% 启动http服务。当前 supervisor 初始化依赖本机 simulator API，因此保留此顺序。
     start_http_server(),

apps/iot/src/mnesia/iot_mnesia.erl

@@ -9,56 +9,48 @@
 
 -include("iot_tables.hrl").
 
--export([init/0, start/0, stop/0]).
+-export([safe_start/0, stop/0]).
 
 -define(TABLES, [efka_client]).
 -define(WAIT_TIMEOUT, 5000).
 
--spec init() -> ok | {error, term()}.
-init() ->
-    with_result(fun() ->
-        _ = mnesia:stop(),
-        ok = mnesia:delete_schema([node()]),
-        ok = mnesia:create_schema([node()]),
-        ok = ensure_persistent_dir(),
-        ok = mnesia:start(),
-        ok = create_tables(),
-        ok = wait_for_tables(),
-        ok
-    end).
+safe_start() ->
+    case ensure_schema() of
+        create_and_start ->
+            ok = mnesia:start(),
+            ok = create_tables(),
+            ok = wait_for_tables();
+        only_start ->
+            ok = mnesia:start(),
+            ok = wait_for_tables()
+    end,
+    log_runtime_info().
 
--spec start() -> ok | {error, term()}.
-start() ->
-    with_result(fun() ->
-        ok = mnesia:start(),
-        ok = ensure_persistent_dir(),
-        ok = wait_for_tables(),
-        ok = verify_tables(),
-        log_runtime_info(),
-        ok
-    end).
+ensure_schema() ->
+    stopped = mnesia:stop(),
+    case mnesia:create_schema([node()]) of
+        ok ->
+            create_and_start;
+        {error, {_, {already_exists, _}}} ->
+            only_start;
+        {error, {_, already_exists}} ->
+            only_start;
+        {error, _Reason} ->
+            only_start
+    end.
 
 -spec stop() -> ok.
 stop() ->
     _ = mnesia:stop(),
     ok.
 
--spec ensure_persistent_dir() -> ok.
-ensure_persistent_dir() ->
-    case mnesia:system_info(use_dir) of
-        true ->
-            ok;
-        false ->
-            throw({mnesia_dir_required, node()})
-    end.
-
 -spec create_tables() -> ok.
 create_tables() ->
     case efka_client_store:ensure_table() of
         ok ->
             ok;
         {error, Reason} ->
-            throw({create_table_failed, {efka_client, Reason}})
+            {error, {create_table_failed, {efka_client, Reason}}}
     end.
 
 -spec wait_for_tables() -> ok.
@@ -67,24 +59,9 @@ wait_for_tables() ->
         ok ->
             ok;
         {timeout, Tables} ->
-            throw({mnesia_tables_timeout, Tables});
+            {error, {mnesia_tables_timeout, Tables}};
         {error, Reason} ->
-            throw({mnesia_tables_error, Reason})
-    end.
-
--spec verify_tables() -> ok.
-verify_tables() ->
-    lists:foreach(fun verify_table/1, ?TABLES),
-    ok.
-
--spec verify_table(atom()) -> ok.
-verify_table(efka_client) ->
-    Expected = record_info(fields, efka_client),
-    case mnesia:table_info(efka_client, attributes) of
-        Expected ->
-            ok;
-        Actual ->
-            throw({table_attributes_mismatch, efka_client, Expected, Actual})
+            {error, {mnesia_tables_error, Reason}}
     end.
 
 -spec log_runtime_info() -> ok.
@@ -94,17 +71,4 @@ log_runtime_info() ->
         mnesia:system_info(directory),
         mnesia:system_info(tables)
     ]),
-    ok.
-
--spec with_result(fun(() -> ok)) -> ok | {error, term()}.
-with_result(Fun) ->
-    try Fun() of
-        ok ->
-            ok
-    catch
-        throw:Reason ->
-            {error, Reason};
-        Class:Reason:Stacktrace ->
-            logger:warning("[iot_mnesia] failed, class: ~p, reason: ~p, stack: ~p", [Class, Reason, Stacktrace]),
-            {error, Reason}
-    end.
+    ok.