test(api): cover the accept logic for `/configs` API

apps/emqx_management/src/emqx_mgmt_api_configs.erl

@@ -122,6 +122,7 @@ schema("/configs") ->
                             }}
                         ]
                 },
+                400 => emqx_dashboard_swagger:error_codes(['INVALID_ACCEPT']),
                 404 => emqx_dashboard_swagger:error_codes(['NOT_FOUND']),
                 500 => emqx_dashboard_swagger:error_codes(['BAD_NODE'])
             }
@@ -349,7 +350,7 @@ configs(put, #{body := Conf, query_string := #{<<"mode">> := Mode}}, _Req) ->
         {error, Errors} -> {400, #{code => 'UPDATE_FAILED', message => ?ERR_MSG(Errors)}}
     end.
 
-find_suitable_accept(Headers, Perferences) ->
+find_suitable_accept(Headers, Perferences) when is_list(Perferences), length(Perferences) > 0 ->
     AcceptVal = maps:get(<<"accept">>, Headers, <<"*/*">>),
     %% Multiple types, weighted with the quality value syntax:
     %% Accept: text/html, application/xhtml+xml, application/xml;q=0.9, image/webp, */*;q=0.8
@@ -362,12 +363,12 @@ find_suitable_accept(Headers, Perferences) ->
     ),
     case lists:member(<<"*/*">>, Accepts) of
         true ->
-            {ok, lists:first(Perferences)};
-        fales ->
+            {ok, lists:nth(1, Perferences)};
+        false ->
             Found = lists:filter(fun(Accept) -> lists:member(Accept, Accepts) end, Perferences),
             case Found of
                 [] -> {error, no_suitalbe_accept};
-                _ -> lists:first(Found)
+                _ -> {ok, lists:nth(1, Found)}
             end
     end.
 

apps/emqx_management/test/emqx_mgmt_api_configs_SUITE.erl

@@ -323,6 +323,36 @@ t_configs_key(_Config) ->
     ?assertEqual(<<"error">>, read_conf([<<"log">>, <<"console">>, <<"level">>])),
     ok.
 
+t_get_configs_in_different_accept(_Config) ->
+    [Key | _] = lists:sort(emqx_conf_cli:keys()),
+    URI = emqx_mgmt_api_test_util:api_path(["configs?key=" ++ Key]),
+    Auth = emqx_mgmt_api_test_util:auth_header_(),
+    Request = fun(Accept) ->
+        Headers = [{"accept", Accept}, Auth],
+        case
+            emqx_mgmt_api_test_util:request_api(get, URI, [], Headers, [], #{return_all => true})
+        of
+            {ok, {{_, Code, _}, RespHeaders, Body}} ->
+                Type = proplists:get_value("content-type", RespHeaders),
+                {Code, Type, Body};
+            {error, {{_, Code, _}, RespHeaders, Body}} ->
+                Type = proplists:get_value("content-type", RespHeaders),
+                {Code, Type, Body}
+        end
+    end,
+
+    %% returns text/palin if text/plain is acceptable
+    ?assertMatch({200, "text/plain", _}, Request(<<"text/plain">>)),
+    ?assertMatch({200, "text/plain", _}, Request(<<"*/*">>)),
+    ?assertMatch(
+        {200, "text/plain", _},
+        Request(<<"application/json, application/xml;q=0.9, image/webp, */*;q=0.8">>)
+    ),
+    %% returns application/json if it only support it
+    ?assertMatch({200, "application/json", _}, Request(<<"application/json">>)),
+    %% returns error if it set to other type
+    ?assertMatch({400, "application/json", _}, Request(<<"application/xml">>)).
+
 %% Helpers
 
 get_config(Name) ->