Add erlfmt and mnesia_test module

Author: michalslaski

rebar.config

@@ -2,6 +2,8 @@
 {deps, []}.
 
 {shell, [
-  % {config, "config/sys.config"},
+    % {config, "config/sys.config"},
     {apps, [elab_demo]}
 ]}.
+
+{project_plugins, [erlfmt]}.

src/elab_demo.app.src

@@ -1,15 +1,16 @@
-{application, elab_demo,
- [{description, "Erlang Lab demo app"},
-  {vsn, "0.1.0"},
-  {registered, []},
-  {mod, {elab_demo_app, []}},
-  {applications,
-   [kernel,
-    stdlib
-   ]},
-  {env,[]},
-  {modules, []},
+{application, elab_demo, [
+    {description, "Erlang Lab demo app"},
+    {vsn, "0.1.0"},
+    {registered, []},
+    {mod, {elab_demo_app, []}},
+    {applications, [
+        kernel,
+        stdlib,
+        mnesia
+    ]},
+    {env, []},
+    {modules, []},
 
-  {licenses, ["Apache 2.0"]},
-  {links, []}
- ]}.
+    {licenses, ["Apache 2.0"]},
+    {links, []}
+]}.

src/elab_demo_sup.erl

@@ -26,10 +26,21 @@ start_link() ->
 %%                  type => worker(),       % optional
 %%                  modules => modules()}   % optional
 init([]) ->
-    SupFlags = #{strategy => one_for_all,
-                 intensity => 0,
-                 period => 1},
-    ChildSpecs = [],
+    SupFlags = #{
+        strategy => one_for_all,
+        intensity => 0,
+        period => 1
+    },
+    ChildSpecs = [
+        #{
+            id => mnesia_test,
+            start => {mnesia_test, start_link, []},
+            restart => temporary,
+            shutdown => brutal_kill,
+            type => worker,
+            modules => [mnesia_test]
+        }
+    ],
     {ok, {SupFlags, ChildSpecs}}.
 
 %% internal functions

src/mnesia_test.erl

@@ -0,0 +1,48 @@
+%%%-------------------------------------------------------------------
+%%% @author Michal Slaski
+%%% @doc 
+%%% Starts a process, which inserts 1M elements to a mnesia table.
+%%% @end
+%%% Created : 25 May 2021 by Michal Slaski
+%%%-------------------------------------------------------------------
+-module(mnesia_test).
+
+-export([
+    start_link/0,
+    init/2,
+    insert_data/2,
+    system_continue/3,
+    system_terminate/4,
+    system_get_state/1
+]).
+
+start_link() ->
+    proc_lib:start_link(?MODULE, init, [self(), 1000000]).
+
+init(Parent, N) ->
+    register(?MODULE, self()),
+    {atomic, ok} = mnesia:create_table(?MODULE, []),
+    Keys = lists:seq(1, N),
+    proc_lib:init_ack(Parent, {ok, self()}),
+    insert_data(Parent, Keys).
+
+insert_data(Parent, [K | Keys]) ->
+    ok = mnesia:dirty_write({?MODULE, K, <<K:32>>}),
+    insert_data(Parent, Keys);
+insert_data(Parent, []) ->
+    loop(Parent).
+
+loop(Parent) ->
+    receive
+        {system, From, Request} ->
+            sys:handle_system_msg(Request, From, Parent, ?MODULE, [], [])
+    end.
+
+system_continue(Parent, _Debug, _State) ->
+    loop(Parent).
+
+system_terminate(Reason, _Parent, _Debug, _State) ->
+    exit(Reason).
+
+system_get_state(_State) ->
+    {ok, mnesia:table_info(?MODULE, all)}.