feat(mongodb): add configurable option to override legacy protocol usage

Fixes https://emqx.atlassian.net/browse/EMQX-10750

Fixes https://github.com/emqx/emqx/discussions/11428

See https://github.com/emqx/mongodb-erlang/pull/39

apps/emqx_authn/src/emqx_authn.app.src

@@ -1,7 +1,7 @@
 %% -*- mode: erlang -*-
 {application, emqx_authn, [
     {description, "EMQX Authentication"},
-    {vsn, "0.1.24"},
+    {vsn, "0.1.25"},
     {modules, []},
     {registered, [emqx_authn_sup, emqx_authn_registry]},
     {applications, [

apps/emqx_bridge_mongodb/test/emqx_bridge_mongodb_SUITE.erl

@@ -29,7 +29,8 @@ group_tests() ->
         t_payload_template,
         t_collection_template,
         t_mongo_date_rule_engine_functions,
-        t_get_status_server_selection_too_short
+        t_get_status_server_selection_too_short,
+        t_use_legacy_protocol_option
     ].
 
 groups() ->
@@ -180,6 +181,7 @@ mongo_config(MongoHost, MongoPort0, rs = Type, Config) ->
             "  replica_set_name = rs0\n"
             "  servers = [~p]\n"
             "  w_mode = safe\n"
+            "  use_legacy_protocol = auto\n"
             "  database = mqtt\n"
             "  resource_opts = {\n"
             "    query_mode = ~s\n"
@@ -205,6 +207,7 @@ mongo_config(MongoHost, MongoPort0, sharded = Type, Config) ->
             "  collection = mycol\n"
             "  servers = [~p]\n"
             "  w_mode = safe\n"
+            "  use_legacy_protocol = auto\n"
             "  database = mqtt\n"
             "  resource_opts = {\n"
             "    query_mode = ~s\n"
@@ -230,6 +233,7 @@ mongo_config(MongoHost, MongoPort0, single = Type, Config) ->
             "  collection = mycol\n"
             "  server = ~p\n"
             "  w_mode = safe\n"
+            "  use_legacy_protocol = auto\n"
             "  database = mqtt\n"
             "  resource_opts = {\n"
             "    query_mode = ~s\n"
@@ -286,10 +290,8 @@ clear_db(Config) ->
     mongo_api:disconnect(Client).
 
 find_all(Config) ->
-    Type = mongo_type_bin(?config(mongo_type, Config)),
-    Name = ?config(mongo_name, Config),
     #{<<"collection">> := Collection} = ?config(mongo_config, Config),
-    ResourceID = emqx_bridge_resource:resource_id(Type, Name),
+    ResourceID = resource_id(Config),
     emqx_resource:simple_sync_query(ResourceID, {find, Collection, #{}, #{}}).
 
 find_all_wait_until_non_empty(Config) ->
@@ -340,6 +342,27 @@ probe_bridge_api(Config, Overrides) ->
     ct:pal("bridge probe result: ~p", [Res]),
     Res.
 
+resource_id(Config) ->
+    Type0 = ?config(mongo_type, Config),
+    Name = ?config(mongo_name, Config),
+    Type = mongo_type_bin(Type0),
+    emqx_bridge_resource:resource_id(Type, Name).
+
+get_worker_pids(Config) ->
+    ResourceID = resource_id(Config),
+    %% abusing health check api a bit...
+    GetWorkerPid = fun(TopologyPid) ->
+        mongoc:transaction_query(TopologyPid, fun(#{pool := WorkerPid}) -> WorkerPid end)
+    end,
+    {ok, WorkerPids = [_ | _]} =
+        emqx_resource_pool:health_check_workers(
+            ResourceID,
+            GetWorkerPid,
+            5_000,
+            #{return_values => true}
+        ),
+    WorkerPids.
+
 %%------------------------------------------------------------------------------
 %% Testcases
 %%------------------------------------------------------------------------------
@@ -494,3 +517,30 @@ t_get_status_server_selection_too_short(Config) ->
         emqx_utils_json:decode(Body)
     ),
     ok.
+
+t_use_legacy_protocol_option(Config) ->
+    ResourceID = resource_id(Config),
+    {ok, _} = create_bridge(Config, #{<<"use_legacy_protocol">> => <<"true">>}),
+    ?retry(
+        _Interval0 = 200,
+        _NAttempts0 = 20,
+        ?assertMatch({ok, connected}, emqx_resource_manager:health_check(ResourceID))
+    ),
+    WorkerPids0 = get_worker_pids(Config),
+    Expected0 = maps:from_keys(WorkerPids0, true),
+    LegacyOptions0 = maps:from_list([{Pid, mc_utils:use_legacy_protocol(Pid)} || Pid <- WorkerPids0]),
+    ?assertEqual(Expected0, LegacyOptions0),
+    {ok, _} = delete_bridge(Config),
+
+    {ok, _} = create_bridge(Config, #{<<"use_legacy_protocol">> => <<"false">>}),
+    ?retry(
+        _Interval0 = 200,
+        _NAttempts0 = 20,
+        ?assertMatch({ok, connected}, emqx_resource_manager:health_check(ResourceID))
+    ),
+    WorkerPids1 = get_worker_pids(Config),
+    Expected1 = maps:from_keys(WorkerPids1, false),
+    LegacyOptions1 = maps:from_list([{Pid, mc_utils:use_legacy_protocol(Pid)} || Pid <- WorkerPids1]),
+    ?assertEqual(Expected1, LegacyOptions1),
+
+    ok.

apps/emqx_machine/src/emqx_machine.app.src

@@ -3,7 +3,7 @@
     {id, "emqx_machine"},
     {description, "The EMQX Machine"},
     % strict semver, bump manually!
-    {vsn, "0.2.11"},
+    {vsn, "0.2.12"},
     {modules, []},
     {registered, []},
     {applications, [kernel, stdlib, emqx_ctl]},

apps/emqx_mongodb/rebar.config

@@ -3,5 +3,5 @@
 {erl_opts, [debug_info]}.
 {deps, [ {emqx_connector, {path, "../../apps/emqx_connector"}}
        , {emqx_resource, {path, "../../apps/emqx_resource"}}
-       , {mongodb, {git, "https://github.com/emqx/mongodb-erlang", {tag, "v3.0.20"}}}
+       , {mongodb, {git, "https://github.com/emqx/mongodb-erlang", {tag, "v3.0.21"}}}
        ]}.

apps/emqx_mongodb/src/emqx_mongodb.app.src

@@ -1,6 +1,6 @@
 {application, emqx_mongodb, [
     {description, "EMQX MongoDB Connector"},
-    {vsn, "0.1.1"},
+    {vsn, "0.1.2"},
     {registered, []},
     {applications, [
         kernel,

apps/emqx_mongodb/src/emqx_mongodb.erl

@@ -141,6 +141,11 @@ mongo_fields() ->
         {pool_size, fun emqx_connector_schema_lib:pool_size/1},
         {username, fun emqx_connector_schema_lib:username/1},
         {password, fun emqx_connector_schema_lib:password/1},
+        {use_legacy_protocol,
+            hoconsc:mk(hoconsc:enum([auto, true, false]), #{
+                default => auto,
+                desc => ?DESC("use_legacy_protocol")
+            })},
         {auth_source, #{
             type => binary(),
             required => false,
@@ -429,6 +434,8 @@ init_worker_options([{w_mode, V} | R], Acc) ->
     init_worker_options(R, [{w_mode, V} | Acc]);
 init_worker_options([{r_mode, V} | R], Acc) ->
     init_worker_options(R, [{r_mode, V} | Acc]);
+init_worker_options([{use_legacy_protocol, V} | R], Acc) ->
+    init_worker_options(R, [{use_legacy_protocol, V} | Acc]);
 init_worker_options([_ | R], Acc) ->
     init_worker_options(R, Acc);
 init_worker_options([], Acc) ->

apps/emqx_retainer/src/emqx_retainer.app.src

@@ -2,7 +2,7 @@
 {application, emqx_retainer, [
     {description, "EMQX Retainer"},
     % strict semver, bump manually!
-    {vsn, "5.0.16"},
+    {vsn, "5.0.17"},
     {modules, []},
     {registered, [emqx_retainer_sup]},
     {applications, [kernel, stdlib, emqx, emqx_ctl]},

changes/ce/feat-11429.en.md

@@ -0,0 +1 @@
+Added option to configure detection of legacy protocol in MondoDB connectors and bridges.

rel/i18n/emqx_mongodb.hocon

@@ -149,4 +149,10 @@ wait_queue_timeout.desc:
 wait_queue_timeout.label:
 """Wait Queue Timeout"""
 
+use_legacy_protocol.desc:
+"""Whether to use MongoDB's legacy protocol for communicating with the database.  The default is to attempt to automatically determine if the newer protocol is supported."""
+
+use_legacy_protocol.label:
+"""Use legacy protocol"""
+
 }