Merge pull request #12285 from HJianBo/shorten-coap-params

feat(coap): support short param names

apps/emqx_gateway_coap/include/emqx_coap.hrl

@@ -14,6 +14,8 @@
 %% limitations under the License.
 %%--------------------------------------------------------------------
 
+-ifndef(EMQX_COAP_HRL).
+
 -define(APP, emqx_coap).
 -define(DEFAULT_COAP_PORT, 5683).
 -define(DEFAULT_COAPS_PORT, 5684).
@@ -79,3 +81,14 @@
 }).
 
 -type coap_message() :: #coap_message{}.
+
+-define(QUERY_PARAMS_MAPPING, [
+    {<<"c">>, <<"clientid">>},
+    {<<"t">>, <<"token">>},
+    {<<"u">>, <<"username">>},
+    {<<"p">>, <<"password">>},
+    {<<"q">>, <<"qos">>},
+    {<<"r">>, <<"retain">>}
+]).
+
+-endif.

apps/emqx_gateway_coap/src/emqx_coap_channel.erl

@@ -386,7 +386,7 @@ check_auth_state(Msg, #channel{connection_required = true} = Channel) ->
         true ->
             call_session(handle_request, Msg, Channel);
         false ->
-            URIQuery = emqx_coap_message:get_option(uri_query, Msg, #{}),
+            URIQuery = emqx_coap_message:extract_uri_query(Msg),
             case maps:get(<<"token">>, URIQuery, undefined) of
                 undefined ->
                     ?SLOG(debug, #{msg => "token_required_in_conn_mode", message => Msg});
@@ -430,7 +430,7 @@ check_token(
 ) ->
     IsDeleteConn = is_delete_connection_request(Msg),
     #{clientid := ClientId} = ClientInfo,
-    case emqx_coap_message:get_option(uri_query, Msg) of
+    case emqx_coap_message:extract_uri_query(Msg) of
         #{
             <<"clientid">> := ClientId,
             <<"token">> := Token
@@ -742,7 +742,7 @@ process_connection(
     Channel = #channel{conn_state = idle},
     Iter
 ) ->
-    Queries = emqx_coap_message:get_option(uri_query, Req),
+    Queries = emqx_coap_message:extract_uri_query(Req),
     case
         emqx_utils:pipeline(
             [
@@ -775,7 +775,7 @@ process_connection(
 ) when
     ConnState == connected
 ->
-    Queries = emqx_coap_message:get_option(uri_query, Req),
+    Queries = emqx_coap_message:extract_uri_query(Req),
     ErrMsg0 =
         case Queries of
             #{<<"clientid">> := ClientId} ->
@@ -793,7 +793,7 @@ process_connection(
         Channel
     );
 process_connection({close, Msg}, _, Channel, _) ->
-    Queries = emqx_coap_message:get_option(uri_query, Msg),
+    Queries = emqx_coap_message:extract_uri_query(Msg),
     case maps:get(<<"clientid">>, Queries, undefined) of
         undefined ->
             ok;

apps/emqx_gateway_coap/src/emqx_coap_message.erl

@@ -6,7 +6,7 @@
 %% Copyright (c) 2015 Petr Gotthard <petr.gotthard@centrum.cz>
 
 %%--------------------------------------------------------------------
-%% Copyright (c) 2017-2023 EMQ Technologies Co., Ltd. All Rights Reserved.
+%% Copyright (c) 2017-2024 EMQ Technologies Co., Ltd. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -43,6 +43,11 @@
     set_payload_block/3, set_payload_block/4
 ]).
 
+-export([
+    extract_uri_query/1,
+    query_params_mapping_table/0
+]).
+
 -include("emqx_coap.hrl").
 
 request(Type, Method) ->
@@ -111,6 +116,12 @@ get_option(Option, Msg) ->
 get_option(Option, #coap_message{options = Options}, Def) ->
     maps:get(Option, Options, Def).
 
+extract_uri_query(Msg = #coap_message{}) ->
+    expand_short_param_name(get_option(uri_query, Msg, #{})).
+
+query_params_mapping_table() ->
+    ?QUERY_PARAMS_MAPPING.
+
 set_payload(Payload, Msg) when is_binary(Payload) ->
     Msg#coap_message{payload = Payload};
 set_payload(Payload, Msg) when is_list(Payload) ->
@@ -149,3 +160,17 @@ to_options(Opts) when is_map(Opts) ->
     Opts;
 to_options(Opts) ->
     maps:from_list(Opts).
+
+expand_short_param_name(Queries) when is_map(Queries) ->
+    lists:foldl(
+        fun({Short, Long}, Acc) ->
+            case maps:take(Short, Acc) of
+                error ->
+                    Acc;
+                {Value, Acc1} ->
+                    maps:put(Long, Value, Acc1)
+            end
+        end,
+        Queries,
+        ?QUERY_PARAMS_MAPPING
+    ).

apps/emqx_gateway_coap/src/emqx_coap_pubsub_handler.erl

@@ -76,7 +76,7 @@ check_topic(Path) ->
 
 get_sub_opts(Msg) ->
     SubOpts = maps:fold(
-        fun parse_sub_opts/3, #{}, emqx_coap_message:get_option(uri_query, Msg, #{})
+        fun parse_sub_opts/3, #{}, emqx_coap_message:extract_uri_query(Msg)
     ),
     case SubOpts of
         #{qos := _} ->
@@ -110,28 +110,24 @@ type_to_qos(coap, #coap_message{type = Type}) ->
     end.
 
 get_publish_opts(Msg) ->
-    case emqx_coap_message:get_option(uri_query, Msg) of
+    Qs = emqx_coap_message:extract_uri_query(Msg),
-        undefined ->
+    maps:fold(
-            #{};
+        fun
-        Qs ->
+            (<<"retain">>, V, Acc) ->
-            maps:fold(
+                Val = V =:= <<"true">>,
-                fun
+                Acc#{retain => Val};
-                    (<<"retain">>, V, Acc) ->
+            (<<"expiry">>, V, Acc) ->
-                        Val = V =:= <<"true">>,
+                Val = erlang:binary_to_integer(V),
-                        Acc#{retain => Val};
+                Acc#{expiry_interval => Val};
-                    (<<"expiry">>, V, Acc) ->
+            (<<"qos">>, V, Acc) ->
-                        Val = erlang:binary_to_integer(V),
+                Val = erlang:binary_to_integer(V),
-                        Acc#{expiry_interval => Val};
+                Acc#{qos => Val};
-                    (<<"qos">>, V, Acc) ->
+            (_, _, Acc) ->
-                        Val = erlang:binary_to_integer(V),
+                Acc
-                        Acc#{qos => Val};
+        end,
-                    (_, _, Acc) ->
+        #{},
-                        Acc
+        Qs
-                end,
+    ).
-                #{},
-                Qs
-            )
-    end.
 
 get_publish_qos(Msg, PublishOpts) ->
     case PublishOpts of

apps/emqx_gateway_coap/src/emqx_gateway_coap.app.src

@@ -1,7 +1,7 @@
 %% -*- mode: erlang -*-
 {application, emqx_gateway_coap, [
     {description, "CoAP Gateway"},
-    {vsn, "0.1.6"},
+    {vsn, "0.1.7"},
     {registered, []},
     {applications, [kernel, stdlib, emqx, emqx_gateway]},
     {env, []},

apps/emqx_gateway_coap/test/emqx_coap_SUITE.erl

@@ -151,6 +151,30 @@ t_connection(_) ->
     end,
     do(Action).
 
+t_connection_with_short_param_name(_) ->
+    Action = fun(Channel) ->
+        %% connection
+        Token = connection(Channel, true),
+
+        timer:sleep(100),
+        ?assertNotEqual(
+            [],
+            emqx_gateway_cm_registry:lookup_channels(coap, <<"client1">>)
+        ),
+
+        %% heartbeat
+        {ok, changed, _} = send_heartbeat(Token, true),
+
+        disconnection(Channel, Token, true),
+
+        timer:sleep(100),
+        ?assertEqual(
+            [],
+            emqx_gateway_cm_registry:lookup_channels(coap, <<"client1">>)
+        )
+    end,
+    do(Action).
+
 t_heartbeat(Config) ->
     Heartbeat = ?config(new_heartbeat, Config),
     Action = fun(Channel) ->
@@ -583,36 +607,67 @@ t_connectionless_pubsub(_) ->
 %% helpers
 
 send_heartbeat(Token) ->
-    HeartURI =
+    send_heartbeat(Token, false).
-        ?MQTT_PREFIX ++
-            "/connection?clientid=client1&token=" ++
-            Token,
 
-    ?LOGT("send heartbeat request:~ts~n", [HeartURI]),
+send_heartbeat(Token, ShortenParamName) ->
-    er_coap_client:request(put, HeartURI).
+    Prefix = ?MQTT_PREFIX ++ "/connection",
+    Queries = #{
+        "clientid" => <<"client1">>,
+        "token" => Token
+    },
+    URI = compose_uri(Prefix, Queries, ShortenParamName),
+    ?LOGT("send heartbeat request:~ts~n", [URI]),
+    er_coap_client:request(put, URI).
 
 connection(Channel) ->
-    URI =
+    connection(Channel, false).
-        ?MQTT_PREFIX ++
+
-            "/connection?clientid=client1&username=admin&password=public",
+connection(Channel, ShortenParamName) ->
+    Prefix = ?MQTT_PREFIX ++ "/connection",
+    Queries = #{
+        "clientid" => <<"client1">>,
+        "username" => <<"admin">>,
+        "password" => <<"public">>
+    },
+    URI = compose_uri(Prefix, Queries, ShortenParamName),
     Req = make_req(post),
     {ok, created, Data} = do_request(Channel, URI, Req),
     #coap_content{payload = BinToken} = Data,
     binary_to_list(BinToken).
 
 disconnection(Channel, Token) ->
-    %% delete
+    disconnection(Channel, Token, false).
-    URI = ?MQTT_PREFIX ++ "/connection?clientid=client1&token=" ++ Token,
+
+disconnection(Channel, Token, ShortenParamName) ->
+    Prefix = ?MQTT_PREFIX ++ "/connection",
+    Queries = #{
+        "clientid" => <<"client1">>,
+        "token" => Token
+    },
+    URI = compose_uri(Prefix, Queries, ShortenParamName),
     Req = make_req(delete),
     {ok, deleted, _} = do_request(Channel, URI, Req).
 
-observe(Channel, Token, true) ->
+observe(Channel, Token, Observe) ->
-    URI = ?PS_PREFIX ++ "/coap/observe?clientid=client1&token=" ++ Token,
+    observe(Channel, Token, Observe, false).
+
+observe(Channel, Token, true, ShortenParamName) ->
+    Prefix = ?PS_PREFIX ++ "/coap/observe",
+    Queries = #{
+        "clientid" => <<"client1">>,
+        "token" => Token
+    },
+    URI = compose_uri(Prefix, Queries, ShortenParamName),
     Req = make_req(get, <<>>, [{observe, 0}]),
     {ok, content, _Data} = do_request(Channel, URI, Req),
     ok;
-observe(Channel, Token, false) ->
+observe(Channel, Token, false, ShortenParamName) ->
-    URI = ?PS_PREFIX ++ "/coap/observe?clientid=client1&token=" ++ Token,
+    Prefix = ?PS_PREFIX ++ "/coap/observe",
+    Queries = #{
+        "clientid" => <<"client1">>,
+        "token" => Token
+    },
+    URI = compose_uri(Prefix, Queries, ShortenParamName),
     Req = make_req(get, <<>>, [{observe, 1}]),
     {ok, nocontent, _Data} = do_request(Channel, URI, Req),
     ok.
@@ -620,8 +675,16 @@ observe(Channel, Token, false) ->
 pubsub_uri(Topic) when is_list(Topic) ->
     ?PS_PREFIX ++ "/" ++ Topic.
 
-pubsub_uri(Topic, Token) when is_list(Topic), is_list(Token) ->
+pubsub_uri(Topic, Token) ->
-    ?PS_PREFIX ++ "/" ++ Topic ++ "?clientid=client1&token=" ++ Token.
+    pubsub_uri(Topic, Token, false).
+
+pubsub_uri(Topic, Token, ShortenParamName) when is_list(Topic), is_list(Token) ->
+    Prefix = ?PS_PREFIX ++ "/" ++ Topic,
+    Queries = #{
+        "clientid" => <<"client1">>,
+        "token" => Token
+    },
+    compose_uri(Prefix, Queries, ShortenParamName).
 
 make_req(Method) ->
     make_req(Method, <<>>).
@@ -701,3 +764,28 @@ get_field(type, #coap_message{type = Type}) ->
     Type;
 get_field(method, #coap_message{method = Method}) ->
     Method.
+
+compose_uri(URI, Queries, ShortenParamName) ->
+    Queries1 = shorten_param_name(ShortenParamName, Queries),
+    case maps:size(Queries1) of
+        0 ->
+            URI;
+        _ ->
+            URI ++ "?" ++ uri_string:compose_query(maps:to_list(Queries1))
+    end.
+
+shorten_param_name(false, Queries) ->
+    Queries;
+shorten_param_name(true, Queries) ->
+    lists:foldl(
+        fun({Short, Long}, Acc) ->
+            case maps:take(Long, Acc) of
+                error ->
+                    Acc;
+                {Value, Acc1} ->
+                    maps:put(Short, Value, Acc1)
+            end
+        end,
+        Queries,
+        emqx_coap_message:query_params_mapping_table()
+    ).

apps/emqx_gateway_coap/test/emqx_coap_message_tests.erl

@@ -0,0 +1,41 @@
+%%--------------------------------------------------------------------
+%% Copyright (c) 2024 EMQ Technologies Co., Ltd. All Rights Reserved.
+%%
+%% Licensed under the Apache License, Version 2.0 (the "License");
+%% you may not use this file except in compliance with the License.
+%% You may obtain a copy of the License at
+%%
+%%     http://www.apache.org/licenses/LICENSE-2.0
+%%
+%% Unless required by applicable law or agreed to in writing, software
+%% distributed under the License is distributed on an "AS IS" BASIS,
+%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+%% See the License for the specific language governing permissions and
+%% limitations under the License.
+%%--------------------------------------------------------------------
+
+-module(emqx_coap_message_tests).
+
+-include_lib("eunit/include/eunit.hrl").
+
+short_name_uri_query_test() ->
+    UriQueryMap = #{
+        <<"c">> => <<"clientid_value">>,
+        <<"t">> => <<"token_value">>,
+        <<"u">> => <<"username_value">>,
+        <<"p">> => <<"password_value">>,
+        <<"q">> => 1,
+        <<"r">> => false
+    },
+    ParsedQuery = #{
+        <<"clientid">> => <<"clientid_value">>,
+        <<"token">> => <<"token_value">>,
+        <<"username">> => <<"username_value">>,
+        <<"password">> => <<"password_value">>,
+        <<"qos">> => 1,
+        <<"retain">> => false
+    },
+    Msg = emqx_coap_message:request(
+        con, put, <<"payload contents...">>, #{uri_query => UriQueryMap}
+    ),
+    ?assertEqual(ParsedQuery, emqx_coap_message:extract_uri_query(Msg)).

changes/ce/fix-12285.en.md

@@ -0,0 +1,2 @@
+The CoAP gateway supports short parameter names for slight savings in datagram size.
+For example, `clientid=bar` can be written as `c=bar`.