Cabol.3.cowboy swagger handler

Makefile

@@ -1,17 +1,21 @@
 PROJECT = cowboy_swagger
 
+CONFIG ?= test/test.config
+
 DEPS = jiffy trails
 
 dep_jiffy  = git https://github.com/davisp/jiffy.git        0.14.2
-dep_trails = git https://github.com/inaka/cowboy-trails.git 0.0.1
+dep_trails = git https://github.com/inaka/cowboy-trails.git 0.0.2
 
 SHELL_DEPS = sync
 
 dep_sync =  git https://github.com/inaka/sync.git 0.1.3
 
-TEST_DEPS = xref_runner
+TEST_DEPS = xref_runner mixer shotgun
 
 dep_xref_runner = git https://github.com/inaka/xref_runner.git 0.2.2
+dep_mixer       = git https://github.com/inaka/mixer.git       0.1.3
+dep_shotgun     = git https://github.com/inaka/shotgun.git     0.1.12
 
 PLT_APPS := trails cowboy
 DIALYZER_DIRS := ebin/
@@ -20,9 +24,10 @@ DIALYZER_OPTS := --verbose --statistics -Werror_handling \
 
 include erlang.mk
 
-SHELL_OPTS = -s sync
-
 # Commont Test Config
 CT_DEPS = xref_runner
+TEST_ERLC_OPTS += +debug_info
+CT_SUITES = cowboy_swagger cowboy_swagger_handler
+CT_OPTS = -cover test/cowboy_swagger.coverspec -erl_args -config ${CONFIG}
 
-CT_OPTS = -cover test/cowboy_swagger.coverspec -erl_args
+SHELL_OPTS = -s sync

src/cowboy_swagger.app.src

@@ -9,7 +9,7 @@
     trails
    ]},
   {modules, []},
-  {mod, {cowboy_swagger, []}},
+  {mod, {cowboy_swagger_app, []}},
   {registered, []}
  ]
 }.

src/cowboy_swagger.erl

@@ -4,6 +4,10 @@
 %% API
 -export([to_json/1]).
 
+%% Utilities
+-export([enc_json/1, dec_json/1]).
+-export([swagger_paths/1]).
+
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% Types.
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
@@ -41,19 +45,35 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 %% @doc Returns the swagger json specification from given `trails'.
--spec to_json(Trails :: [trails:trail()]) -> iolist().
+-spec to_json([trails:trail()]) -> iolist().
 to_json(Trails) ->
   SwaggerSpec = #{paths => swagger_paths(Trails)},
-  jiffy:encode(SwaggerSpec, [uescape]).
+  enc_json(SwaggerSpec).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-%% Private API.
+%% Utilities.
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
-%% @private
+-spec enc_json(jiffy:json_value()) -> iolist().
+enc_json(Json) ->
+  jiffy:encode(Json, [uescape]).
+
+-spec dec_json(iodata()) -> jiffy:json_value().
+dec_json(Data) ->
+  try jiffy:decode(Data, [return_maps])
+  catch
+    _:{error, _} ->
+      throw(bad_json)
+  end.
+
+-spec swagger_paths([trails:trail()]) -> map().
 swagger_paths(Trails) ->
   swagger_paths(Trails, #{}).
 
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Private API.
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
 %% @private
 swagger_paths([], Acc) ->
   Acc;

src/cowboy_swagger_app.erl

@@ -0,0 +1,15 @@
+%%% @hidden
+-module(cowboy_swagger_app).
+
+-behaviour(application).
+
+%% Application callbacks
+-export([start/2, stop/1]).
+
+-spec start(term(), term()) -> {error, term()} | {ok, pid()}.
+start(_Type, _Args) ->
+  cowboy_swagger_sup:start_link().
+
+-spec stop(term()) -> ok.
+stop(_State) ->
+  ok.

src/cowboy_swagger_handler.erl

@@ -0,0 +1,58 @@
+-module(cowboy_swagger_handler).
+
+%% Cowboy callbacks
+-export([ init/3
+        , rest_init/2
+        , content_types_provided/2
+        ]).
+
+%% Handlers
+-export([handle_get/2]).
+
+%% Trails
+-behaviour(trails_handler).
+-export([trails/0]).
+
+-type state() :: #{}.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%% Cowboy Callbacks
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-spec init({atom(), atom()}, cowboy_req:req(), state()) ->
+  {upgrade, protocol, cowboy_rest}.
+init(_Transport, _Req, _Opts) ->
+  {upgrade, protocol, cowboy_rest}.
+
+-spec rest_init(cowboy_req:req(), state()) ->
+  {ok, cowboy_req:req(), term()}.
+rest_init(Req, _Opts) ->
+  {ok, Req, #{}}.
+
+-spec content_types_provided(cowboy_req:req(), state()) ->
+  {[term()], cowboy_req:req(), state()}.
+content_types_provided(Req, State) ->
+  {[{<<"application/json">>, handle_get}], Req, State}.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%% Handlers
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% @hidden
+handle_get(Req, State) ->
+  Trails = trails:all(),
+  {cowboy_swagger:to_json(Trails), Req, State}.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%%% Trails
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+%% @hidden
+trails() ->
+  MD =
+    #{get =>
+      #{description => "Retrives swagger's specification.",
+        produces => ["application/json"]
+      }
+    },
+  [trails:trail("/api-docs/swagger.json", cowboy_swagger_handler, [], MD)].

src/cowboy_swagger_sup.erl

@@ -0,0 +1,14 @@
+%%% @hidden
+-module(cowboy_swagger_sup).
+
+-behaviour(supervisor).
+
+-export([init/1]).
+-export([start_link/0]).
+
+-spec start_link() -> {ok, pid()} | {error, term()}.
+start_link() -> supervisor:start_link({local, ?MODULE}, ?MODULE, []).
+
+-spec init([]) -> {ok, {{one_for_one, 10, 60}, []}}.
+init([]) ->
+  {ok, {{one_for_one, 10, 60}, []}}.

test/cowboy_swagger.coverspec

@@ -1,5 +1,8 @@
 %% Specific modules to include in cover.
 {
  incl_mods,
- [cowboy_swagger]
+ [
+  cowboy_swagger,
+  cowboy_swagger_handler
+ ]
 }.

test/cowboy_swagger_SUITE.erl

@@ -1,35 +1,29 @@
 -module(cowboy_swagger_SUITE).
 
-%% CT
--export([all/0, init_per_suite/1, end_per_suite/1]).
+-include_lib("mixer/include/mixer.hrl").
+-mixin([
+        {cowboy_swagger_test_utils,
+         [ init_per_suite/1
+         , end_per_suite/1
+         ]}
+       ]).
 
-%% Test cases
+-export([all/0]).
 -export([to_json_test/1]).
 
--type config() :: [{atom(), term()}].
-
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% Common test
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
 -spec all() -> [atom()].
 all() ->
-  Exports = ?MODULE:module_info(exports),
-  [F || {F, 1} <- Exports, F /= module_info].
-
--spec init_per_suite(config()) -> config().
-init_per_suite(Config) ->
-  Config.
-
--spec end_per_suite(config()) -> config().
-end_per_suite(Config) ->
-  Config.
+  cowboy_swagger_test_utils:all(?MODULE).
 
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 %% Test Cases
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 
--spec to_json_test(config()) -> {atom(), string()}.
+-spec to_json_test(cowboy_swagger_test_utils:config()) -> {atom(), string()}.
 to_json_test(_Config) ->
   Trails = test_trails(),
   SwaggerJson = cowboy_swagger:to_json(Trails),

test/cowboy_swagger_handler_SUITE.erl

@@ -0,0 +1,55 @@
+-module(cowboy_swagger_handler_SUITE).
+
+%% CT
+-export([ all/0
+        , init_per_suite/1
+        , end_per_suite/1
+        ]).
+
+%% Test cases
+-export([handler_test/1]).
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Common test
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-spec all() -> [atom()].
+all() ->
+  cowboy_swagger_test_utils:all(?MODULE).
+
+-spec init_per_suite(
+  cowboy_swagger_test_utils:config()
+) -> cowboy_swagger_test_utils:config().
+init_per_suite(Config) ->
+  shotgun:start(),
+  example:start(),
+  Config.
+
+-spec end_per_suite(
+  cowboy_swagger_test_utils:config()
+) -> cowboy_swagger_test_utils:config().
+end_per_suite(Config) ->
+  shotgun:stop(),
+  example:stop(),
+  Config.
+
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+%% Test Cases
+%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
+
+-spec handler_test(cowboy_swagger_test_utils:config()) -> {atom(), string()}.
+handler_test(_Config) ->
+  %% Expected result
+  Trails = trails:trails([example_echo_handler,
+                          example_description_handler,
+                          cowboy_swagger_handler]),
+  ExpectedPaths = cowboy_swagger:dec_json(
+    cowboy_swagger:enc_json(cowboy_swagger:swagger_paths(Trails))),
+
+  %% GET swagger.json spec
+  ct:comment("GET /api-docs/swagger.json should return 200 OK"),
+  #{status_code := 200, body := Body0} =
+    cowboy_swagger_test_utils:api_call(get, "/api-docs/swagger.json"),
+  #{<<"paths">> := ExpectedPaths} = cowboy_swagger:dec_json(Body0),
+
+  {comment, ""}.

test/cowboy_swagger_test_utils.erl

@@ -0,0 +1,46 @@
+-module(cowboy_swagger_test_utils).
+
+-export([ all/1
+        , init_per_suite/1
+        , end_per_suite/1
+        ]).
+-export([ api_call/2
+        , api_call/3
+        , api_call/4
+        ]).
+
+-type config() :: proplists:proplist().
+-export_type([config/0]).
+
+-spec all(atom()) -> [atom()].
+all(Module) ->
+  ExcludedFuns = [module_info, init_per_suite, end_per_suite, group, all],
+  Exports = Module:module_info(exports),
+  [F || {F, 1} <- Exports, not lists:member(F, ExcludedFuns)].
+
+-spec init_per_suite(config()) -> config().
+init_per_suite(Config) ->
+  Config.
+
+-spec end_per_suite(config()) -> config().
+end_per_suite(Config) ->
+  Config.
+
+-spec api_call(atom(), string()) -> #{}.
+api_call(Method, Uri) ->
+  api_call(Method, Uri, #{}).
+
+-spec api_call(atom(), string(), #{}) -> #{}.
+api_call(Method, Uri, Headers) ->
+  api_call(Method, Uri, Headers, []).
+
+-spec api_call(atom(), string(), #{}, iodata()) -> #{}.
+api_call(Method, Uri, Headers, Body) ->
+  Port = application:get_env(example, http_port, 8080),
+  {ok, Pid} = shotgun:open("localhost", Port),
+  try
+    {ok, Response} = shotgun:request(Pid, Method, Uri, Headers, Body, #{}),
+    Response
+  after
+    shotgun:close(Pid)
+  end.

test/example.app

@@ -0,0 +1,16 @@
+{application, example,
+ [
+  {description, "Cowboy Trails Basic Example."},
+  {vsn, "0.1"},
+  {applications,
+   [kernel,
+    stdlib,
+    cowboy,
+    trails,
+    cowboy_swagger
+   ]},
+  {modules, []},
+  {mod, {example, []}},
+  {start_phases, [{start_trails_http, []}]}
+ ]
+}.