Merge pull request #2 from inaka/jfacorro.1.katana.maps

[#1] get/[2,3] nested maps.

.gitignore

@@ -9,3 +9,4 @@ logs
 bin
 ebin
 deps
+.erlang.mk.*

Makefile

@@ -1,2 +1,12 @@
 PROJECT = katana
+
+DEPS = sync
+
+dep_sync = git https://github.com/rustyio/sync.git master
+
 include erlang.mk
+
+CT_SUITES = ktn_maps
+
+shell: app
+	erl -pa ebin -pa deps/*/ebin -s sync

src/ktn_maps.erl

@@ -0,0 +1,39 @@
+-module(ktn_maps).
+
+-export([
+         get/2,
+         get/3
+        ]).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%% Public API
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-spec get(term(), map()) -> term().
+get(Keys, Map) ->
+    get(Keys, Map, undefined, error).
+
+-spec get(term(), map(), term()) -> term().
+get(Keys, Map, Default) ->
+    get(Keys, Map, Default, default).
+
+%% @private
+-spec get(term(), map(), term(), error | default) -> term().
+get([Key], Map, Default, Type) ->
+    get(Key, Map, Default, Type);
+get([Key | Rest], Map, Default, Type) ->
+    case get(Key, Map, Default, Type) of
+        NewMap when is_map(NewMap) ->
+            get(Rest, NewMap, Default, Type);
+        _ ->
+            Default
+    end;
+get(Key, Map, Default, Type) ->
+    case {Type, maps:is_key(Key, Map)} of
+        {_, true} ->
+            maps:get(Key, Map);
+        {default, false} ->
+            Default;
+        {error, false} ->
+            error(bad_path)
+    end.

test/ktn_maps_SUITE.erl

@@ -0,0 +1,121 @@
+-module(ktn_maps_SUITE).
+
+-export([
+         all/0,
+         init_per_suite/1,
+         end_per_suite/1
+        ]).
+
+-export([
+         find_nested_values/1,
+         find_shallow_values/1,
+         dont_find_nested_values/1,
+         dont_find_shallow_values/1,
+         provide_default/1
+        ]).
+
+-define(EXCLUDED_FUNS,
+        [
+         module_info,
+         all,
+         test,
+         init_per_suite,
+         end_per_suite
+        ]).
+
+-type config() :: [{atom(), term()}].
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Common test
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-spec all() -> [atom()].
+all() ->
+    Exports = ?MODULE:module_info(exports),
+    [F || {F, _} <- Exports, not lists:member(F, ?EXCLUDED_FUNS)].
+
+-spec init_per_suite(config()) -> config().
+init_per_suite(Config) ->
+    Map = #{user => "john.doe",
+            name => "John",
+            last_name => "Doe",
+            location => #{latitude => 1.5,
+                          longitude => 2.5},
+            conversation => #{destination => #{ip => "127.0.0.1",
+                                               port => 8080}}
+           },
+    [{map, Map} | Config].
+
+-spec end_per_suite(config()) -> config().
+end_per_suite(Config) ->
+    Config.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Test Cases
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-spec find_nested_values(config()) -> ok.
+find_nested_values(Config) ->
+    Map = proplists:get_value(map, Config),
+    8080 = ktn_maps:get([conversation, destination, port], Map),
+    1.5 = ktn_maps:get([location, latitude], Map).
+
+-spec find_shallow_values(config()) -> ok.
+find_shallow_values(Config) ->
+    Map = proplists:get_value(map, Config),
+    "john.doe" = ktn_maps:get(user, Map),
+    "John" = ktn_maps:get(name, Map),
+    "Doe" = ktn_maps:get(last_name, Map),
+    "john.doe" = ktn_maps:get([user], Map).
+
+-spec dont_find_nested_values(config()) -> ok.
+dont_find_nested_values(Config) ->
+    Map = proplists:get_value(map, Config),
+    ok = try
+             ktn_maps:get([address, country, city], Map)
+         catch
+             error:bad_path -> ok
+         end,
+    ok = try
+             ktn_maps:get([social, facebook], Map)
+         catch
+             error:bad_path -> ok
+         end.
+
+-spec dont_find_shallow_values(config()) -> ok.
+dont_find_shallow_values(Config) ->
+    Map = proplists:get_value(map, Config),
+    ok = try
+             ktn_maps:get(username, Map)
+         catch
+             error:bad_path -> ok
+         end,
+    ok = try
+             ktn_maps:get(email, Map)
+         catch
+             error:bad_path -> ok
+         end,
+    ok = try
+             ktn_maps:get([email], Map)
+         catch
+             error:bad_path -> ok
+         end.
+
+-spec provide_default(config()) -> ok.
+provide_default(Config) ->
+    Map = proplists:get_value(map, Config),
+
+    8080 = ktn_maps:get([conversation, destination, port], Map, default),
+    1.5 = ktn_maps:get([location, latitude], Map, default),
+
+    "john.doe" = ktn_maps:get(user, Map, default),
+    "John" = ktn_maps:get(name, Map, default),
+    "Doe" = ktn_maps:get(last_name, Map, default),
+    "john.doe" = ktn_maps:get([user], Map, default),
+
+    default = ktn_maps:get([address, country, city], Map, default),
+    default = ktn_maps:get([social, facebook], Map, default),
+
+    default = ktn_maps:get(username, Map, default),
+    default = ktn_maps:get(email, Map, default),
+    default = ktn_maps:get([email], Map, default).