[#28] Implement shards:new/3.

README.md

@@ -282,19 +282,19 @@ distributed.
 Node `a`:
 
 ```
-$ erl -sname a@localhost -pa _build/default/lib/*/ebin -s shards
+$ rebar3 shell --sname a@localhost
 ```
 
 Node `b`:
 
 ```
-$ erl -sname b@localhost -pa _build/default/lib/*/ebin -s shards
+$ rebar3 shell --sname b@localhost
 ```
 
 Node `c`:
 
 ```
-$ erl -sname c@localhost -pa _build/default/lib/*/ebin -s shards
+$ rebar3 shell --sname c@localhost
 ```
 
 **2.** Create a table with global scope (`{scope, g}`) on each node:

rebar.config

@@ -26,6 +26,26 @@
 
 {deps, []}.
 
+%% == Common Test ==
+
+{ct_compile_opts, [
+  debug_info,
+  warnings_as_errors,
+  warn_unused_vars,
+  ewarn_export_all,
+  warn_shadow_vars,
+  warn_unused_import,
+  warn_unused_function,
+  warn_bif_clash,
+  warn_unused_record,
+  warn_deprecated_function,
+  warn_obsolete_guard,
+  strict_validation,
+  warn_export_vars,
+  warn_exported_vars,
+  warn_untyped_record
+]}.
+
 %% == EDoc ==
 
 {edoc_opts, []}.

src/shards.erl

@@ -43,7 +43,7 @@
   match_spec_compile/1,
   match_spec_run/2,
   member/2,
-  new/2,
+  new/2, new/3,
   next/2,
   prev/2,
   safe_fixtable/2,
@@ -453,6 +453,10 @@ new(Name, Options) ->
     _          -> shards_local:new(Name, Options)
   end.
 
+%% @equiv shards_dist:new(Name, Options, Nodes)
+new(Name, Options, Nodes) ->
+  shards_dist:new(Name, Options, Nodes).
+
 %% @doc
 %% Wrapper to `shards_local:next/3' and `shards_dist:next/3'.
 %%

src/shards_dist.erl

@@ -17,7 +17,7 @@
   delete/1, delete/3,
   delete_all_objects/2,
   delete_object/3,
-  new/2,
+  new/2, new/3,
   insert/3,
   insert_new/3,
   lookup/3,
@@ -58,7 +58,8 @@ join(Tab, Nodes) ->
   get_nodes(Tab).
 
 %% @private
-join_(Tab) -> pg2:join(Tab, whereis(Tab)).
+join_(Tab) ->
+  pg2:join(Tab, whereis(Tab)).
 
 -spec leave(Tab, Nodes) -> LeavedNodes when
   Tab         :: atom(),
@@ -239,6 +240,18 @@ member(Tab, Key, State) ->
 new(Name, Options) ->
   shards_local:new(Name, Options).
 
+-spec new(Name, Options, Nodes) -> Name when
+  Name    :: atom(),
+  Options :: [shards_local:option()],
+  Nodes   :: [node()].
+new(Name, Options, Nodes) ->
+  AllNodes = lists:usort([node() | Nodes]),
+  global:trans({?MODULE, Name}, fun() ->
+    rpc:multicall(AllNodes, shards, new, [Name, Options])
+  end),
+  _ = join(Name, AllNodes),
+  Name.
+
 -spec select(Tab, MatchSpec, State) -> [Match] when
   Tab       :: atom(),
   MatchSpec :: ets:match_spec(),

src/shards_owner_sup.erl

@@ -16,9 +16,6 @@
 %% Macro to setup a supervisor worker
 -define(worker(Mod, Args, Spec), child(worker, Mod, Args, Spec)).
 
-%% Default number of shards
--define(N_SHARDS, erlang:system_info(schedulers_online)).
-
 %% Macro to check if restart strategy is allowed
 -define(is_restart_strategy(S_), S_ == one_for_one; S_ == one_for_all).
 

test/test_helper.hrl

@@ -1,6 +1,6 @@
 %%%-------------------------------------------------------------------
 %%% @doc
-%%% Common definitions.
+%%% Commons.
 %%% @end
 %%%-------------------------------------------------------------------