Merge pull request #1 from artefactop/otp_behaviour

Otp behaviour

src/cache.app.src

@@ -1,7 +1,7 @@
 {application, cache,
    [
       {description, "in-memory cache"},
-      {vsn,         "0.1.0"},
+      {vsn,         "git"},
       {modules,     [
          cache,
          cache_sup, 

src/cache.erl

@@ -1,8 +1,27 @@
 -module(cache).
+
 -export([start/0]).
--export([start_link/2, i/1, put/3, get/2, evict/1, stop/1]).
+-export([
+    start_link/0,
+    start_link/1,
+    start_link/2, 
+    i/0, 
+    i/1, 
+    put/2, 
+    put/3, 
+    put_ttl/3,
+    put_ttl/4,
+    get/1, 
+    get/2, 
+    evict/0, 
+    evict/1, 
+    stop/0, 
+    stop/1
+]).
 
+-define(NAME, cache).
 
+%%
 start() ->
    AppFile = code:where_is_file(atom_to_list(?MODULE) ++ ".app"),
    {ok, [{application, _, List}]} = file:consult(AppFile),
@@ -18,32 +37,79 @@ start() ->
    ),
    application:start(?MODULE).
 
+%%
+start_link() ->
+    Env = proplists:delete(included_applications, application:get_all_env()),
+    start_link(?NAME, Env).
+    
+start_link(Opts) ->
+    start_link(?NAME, Opts).
 
-%%
-%%
 start_link(Name, Opts) ->
-   cache_bucket:start_link(Name, Opts).
+    cache_bucket:start_link(Name, Opts).
+
+i() ->
+    i(?NAME).  
 
 i(Cache) ->
-   cache_bucket:i(Cache).   
+    cache_bucket:i(Cache).   
 
 %%
 %%
+
+-spec put(Key::term(), Val::term()) -> ok.
+
+put(Key, Val) ->
+    put(?NAME, Key, Val).
+
+-spec put(Cache::atom(), Key::term(), Val::term()) -> ok.
+
 put(Cache, Key, Val) ->
-   cache_bucket:put(Cache, Key, Val).
+    cache_bucket:put(Cache, Key, Val).
+
+-spec put_ttl(Key::term(), Val::term(), TTL::non_neg_integer()) -> ok.
+
+put_ttl(Key, Val, TTL) when is_integer(TTL) ->
+    put_ttl(?NAME, Key, Val, TTL).
+
+-spec put_ttl(Cache::atom(), Key::term(), Val::term(), TTL::non_neg_integer()) -> ok.
+
+put_ttl(Cache, Key, Val, TTL) when is_integer(TTL) ->
+    cache_bucket:put_ttl(Cache, Key, Val, TTL * 1000000).
 
 %%
 %%
+-spec get(Key::term()) -> {ok, value} | none.
+
+get(Key) ->
+    get(?NAME, Key).
+
+-spec get(Cache::atom(), Key::term()) -> {ok, value} | none.
+
 get(Cache, Key) ->
-   cache_bucket:get(Cache, Key).
+    cache_bucket:get(Cache, Key).
 
 %%
 %%
+-spec evict() -> ok.
+
+evict() ->
+    evict(?NAME).
+
+-spec evict(Cache::atom()) -> ok.
+
 evict(Cache) ->
-   cache_bucket:evict(Cache).
+    cache_bucket:evict(Cache).
 
 %%
 %%
+-spec stop() -> ok.
+
+stop() ->
+    stop(?NAME).
+
+-spec stop(Cache::atom()) -> ok.
+
 stop(Cache) ->
-   cache_bucket:stop(Cache).
+    cache_bucket:stop(Cache).
 

src/cache_bucket.erl

@@ -4,7 +4,7 @@
 -author('Dmitry Kolesnikov <dmkolesnikov@gmail.com>').
 
 -export([start_link/2]).
--export([i/1, put/3, get/2, evict/1, stop/1]).
+-export([i/1, put/3, put_ttl/4, get/2, evict/1, stop/1]).
 -export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2, code_change/3]).
 
 -define(DEFAULT_POLICY,     lru).
@@ -85,6 +85,9 @@ i(Cache) ->
 put(Cache, Key, Val) ->
 	gen_server:cast(Cache, {put, Key, Val}).
 
+put_ttl(Cache, Key, Val, TTL) ->
+   gen_server:cast(Cache, {put, Key, Val, TTL}).
+
 get(Cache, Key) ->
    gen_server:call(Cache, {get, Key}, infinity).
 
@@ -113,16 +116,16 @@ handle_call(info, _Tx,  #cache{elements=E, access=A, hit=Hit, miss=Miss}=S) ->
    ],
    {reply, {ok, Info}, S};
 
-handle_call({get, Key}, _Tx, #cache{ttl=TTL, elements=E, access=A, hit=Hit, miss=Miss}=S) ->
+handle_call({get, Key}, _Tx, #cache{elements=E, access=A, hit=Hit, miss=Miss}=S) ->
    Now = usec(),
    case ets:lookup(E, Key) of
    	[] -> 
    	   {reply, none, S#cache{miss=Miss + 1}};
-   	[{Key, _Val, Expire0}] when Expire0 =< Now ->
+   	[{Key, _Val, Expire0, _TTL}] when Expire0 =< Now ->
    	   {reply, none, S#cache{miss=Miss + 1}};
-   	[{Key, Val, Expire0}] ->
+   	[{Key, Val, Expire0, TTL}] ->
    	   Expire = Now + TTL,
-   		ets:insert(E, {Key, Val, Expire}),
+   		ets:insert(E, {Key, Val, Expire, TTL}),
    		ets:delete(A, Expire0),
    		ets:insert(A, {Expire, Key}),
    	   {reply, {ok, Val}, S#cache{hit=Hit + 1}}
@@ -136,9 +139,15 @@ handle_call(_Req,  _Tx, S) ->
 
 %%
 %%
+handle_cast({put, Key, Val, TTL}, #cache{elements=E, access=A}=S) ->
+   Expire = usec() + TTL,
+   ets:insert(E, {Key, Val, Expire, TTL}),
+   ets:insert(A, {Expire, Key}),
+   {noreply, S};
+
 handle_cast({put, Key, Val}, #cache{ttl=TTL, elements=E, access=A}=S) ->
    Expire = usec() + TTL,
-   ets:insert(E, {Key, Val, Expire}),
+   ets:insert(E, {Key, Val, Expire, TTL}),
    ets:insert(A, {Expire, Key}),
    {noreply, S};
 
@@ -182,7 +191,7 @@ code_change(_Vsn, S, _Extra) ->
 %%
 %%
 usec() ->
-   {Mega, Sec, USec} = erlang:now(),
+   {Mega, Sec, USec} = os:timestamp(),
    (Mega * 1000000 + Sec) * 1000000 + USec.
 
 %%

src/cache_sup.erl

@@ -2,18 +2,32 @@
 -module(cache_sup).
 -behaviour(supervisor).
 -author('Dmitry Kolesnikov <dmkolesnikov@gmail.com>').
+-author('Jose Luis Navarro <jlnavarro@gmail.com>').
 
--export([start_link/0, init/1]).
+%% API
+-export([start_link/0]).
+
+%% Supervisor callbacks
+-export([init/1]).
+
+%% Helper macro for declaring children of supervisor
+-define(CHILD(I, Type), {I, {I, start_link, []}, permanent, 5000, Type, [I]}).
+
+%% ===================================================================
+%% API functions
+%% ===================================================================
 
-%%
-%%
 start_link() ->
    supervisor:start_link({local, ?MODULE}, ?MODULE, []).
    
+%% ===================================================================
+%% Supervisor callbacks
+%% ===================================================================
+
 init([]) ->
-   {ok,
+    {ok,
       {
          {one_for_one, 4, 1800},
-         []
+         [?CHILD(cache, worker)]
       }
-   }.
+    }.

test/cache_tests.erl

@@ -54,6 +54,21 @@ lifecyle_3_test() ->
    {ok, val4} = cache:get(test, key4),
    cache:stop(test).
 
+lifecyle_ttl_test() ->
+   cache:start(),
+   ok = cache:put_ttl(key1, val1, 1),
+   ok = cache:put_ttl(key2, val2, 1),
+   timer:sleep(1000),
+   ok = cache:put_ttl(key3, val3, 1),   
+   ok = cache:put_ttl(key4, val4, 1),
+   timer:sleep(950),
+
+   none = cache:get(key1),
+   none = cache:get(key2),
+   {ok, val3} = cache:get(key3),
+   {ok, val4} = cache:get(key4),
+   cache:stop().
+
 evict_lru_1_test() ->
    cache:start(),
    {ok, _} = cache:start_link(test, [