Add db:size/0 and some error checking.

1 files changed, 15 insertions, 8 deletions

diff --git a/src/db.erl b/src/db.erl
index 50117e4..08960f7 100644
--- a/src/db.erl
+++ b/src/db.erl
@@ -4,7 +4,7 @@
 %% API.
 -export([start_link/0, stop/0]).
 -export([init_db/0, init_db/1, init_tables/0, init_tables/1]).
--export([add/1, find/1, get_by_index/2]).
+-export([add/1, find/1, get_by_index/2, size/0]).
 %% API for testing.
 -export([dump/1, destroy_tables/0, info_tables/0, dump_to_file/1]).
 %% gen_server callbacks.
@@ -37,18 +37,24 @@ init_tables(Nodes) ->
     DiscCopies = [],
     DiscOnlyCopies = Nodes,
     mnesia:start(),
-    mnesia:create_table(plop, [{type, set},
-                               {ram_copies, RamCopies},
-                               {disc_copies, DiscCopies},
-                               {disc_only_copies, DiscOnlyCopies},
-                               {attributes, record_info(fields, plop)}]),
-    mnesia:add_table_index(plop, hash).
+    {atomic, ok} =
+        mnesia:create_table(plop,
+                            [{type, set},
+                             {ram_copies, RamCopies},
+                             {disc_copies, DiscCopies},
+                             {disc_only_copies, DiscOnlyCopies},
+                             {attributes, record_info(fields, plop)},
+                             {majority, true}]),
+    {atomic, ok} = mnesia:add_table_index(plop, hash).
+
 destroy_tables() ->
     mnesia:delete_table(plop).
 info_tables() ->
     mnesia:table_info(plop, all).
 dump_to_file(Filename) ->
     mnesia:dump_to_textfile(Filename).
+size() ->
+    mnesia:table_info(plop, size).
 
 init(_Args) ->
     {mnesia:wait_for_tables([plop], 5000), []}.
@@ -59,6 +65,7 @@ start_link() ->
 stop() ->
     gen_server:call(?MODULE, stop).
 
+%% API.
 add(Entry) ->
     gen_server:call(?MODULE, {add, Entry}).
 
@@ -119,5 +126,5 @@ handle_call({get_by_index, {Start, End}}, _From, State) ->
                 Result = ['$2'],
                 mnesia:select(plop, [{MatchHead, Guard, Result}])
         end,
-    Res = mnesia:transaction(F),
+    {atomic, Res} = mnesia:transaction(F),
     {reply, Res, State}.