implement gen_server

src/interval_srv.erl

@@ -0,0 +1,62 @@
+%% Copyright
+-module(interval_srv).
+-author("eshubin").
+
+-behaviour(gen_server).
+
+%% API
+-export([start_link/1, find/1]).
+
+%% gen_server
+-export([init/1, handle_call/3, handle_cast/2, handle_info/2, terminate/2,
+  code_change/3]).
+
+%% API
+start_link(FileName) ->
+  gen_server:start_link({local, ?MODULE}, ?MODULE, FileName, []).
+
+find(N) ->
+  gen_server:call(?MODULE, {point, N}).
+
+%% gen_server callbacks
+-record(state, {tree}).
+
+init(FileName) ->
+  {ok, #state{tree = interval_container:new(interval_reader:read(FileName))}}.
+
+handle_call({point, N}, _From, #state{tree = Tree} = State) ->
+  R = interval_container:find(N, Tree),
+  {reply, R, State}.
+
+handle_cast(_Request, State) ->
+  {noreply, State}.
+
+handle_info(_Info, State) ->
+  {noreply, State}.
+
+terminate(_Reason, _State) ->
+  ok.
+
+code_change(_OldVsn, State, _Extra) ->
+  {ok, State}.
+
+-include_lib("eunit/include/eunit.hrl").
+
+interval_srv_test_() ->
+  {
+    setup,
+    fun() ->
+      start_link("../priv/two_intervals")
+    end,
+    fun(_) ->
+      [
+        ?_assertEqual(not_found, find(4)),
+        ?_assertEqual(not_found, find(365916480007)),
+        ?_assertEqual(not_found, find(506822291477)),
+        ?_assertEqual({{401297465489,406822291477}, 0.5527523660317453}, find(401298465489)),
+        ?_assertEqual({{13935775370,365916480006}, 0.8678967605514785}, find(13935775371)),
+        ?_assertEqual({{13935775370,365916480006}, 0.8678967605514785}, find(365916480006)),
+        ?_assertEqual({{13935775370,365916480006}, 0.8678967605514785}, find(13935775370))
+      ]
+    end
+  }.