Upgrade ranch 1.7.0 → 2.2.0

Ranch 2.x breaking changes addressed:
- Protocol callback changed from start_link/4 (Ref, Socket, Transport, Opts)
  to start_link/3 (Ref, Transport, Opts); socket obtained via ranch:handshake/1
- ranch:info/0 now returns #{Name => #{...}} instead of [{Name, [proplists]}];
  updated mtp_listeners/0, running_ports/0, and config_change_case test

Also update AGENTS.md with CT failure debugging workflow.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: seriyps

AGENTS.md

@@ -79,6 +79,25 @@ Individual steps:
 
 Always run `make test` before committing. Fix all xref warnings and dialyzer errors — they are treated as errors.
 
+### Debugging CT failures
+
+When `rebar3 ct` (or `make test`) reports failures, **do not rely on the terminal output** — it is truncated and shows only the last error. Instead, go straight to the HTML logs:
+
+```
+_build/test/logs/ct_run.<timestamp>/lib.mtproto_proxy.logs/run.<timestamp>/
+```
+
+Key files:
+- `suite.log` — machine-readable summary; `=case` lines show test order, `=result failed` shows which failed
+- `single_dc_suite.<test_name>.html` — full log for one test case (strip HTML tags to read: `sed 's/<[^>]*>//g'`)
+- `suite.log.html` / `index.html` — human-readable in a browser
+
+Workflow:
+1. Run `make test` — note how many pass/fail
+2. Check `suite.log` for `=case` ordering and `=result failed` to identify the failing test
+3. Read that test's `.html` log for the full stacktrace and system reports
+4. Fix, then re-run `make test`. If tests still fail spuriously, try `rm -rf _build/test && make test` to clear stale test artifacts (removing only `_build/test` is faster than a full clean build).
+
 ## Code Style
 
 - Language: **Erlang**. Follow standard Erlang OTP conventions.

rebar.config

@@ -1,7 +1,7 @@
 % -*- mode: erlang -*-
 {erl_opts, [debug_info]}.
 
-{deps, [{ranch, "1.7.0"},
+{deps, [{ranch, "2.2.0"},
         {erlang_psq, {git, "https://github.com/seriyps/psq", {branch, "master"}}}
         ]}.
 {project_plugins, [rebar3_proper,

rebar.lock

@@ -3,10 +3,10 @@
   {git,"https://github.com/seriyps/psq",
        {ref,"46329ccb60f27d7d4c3f3643441ccef6c5f9c89c"}},
   0},
- {<<"ranch">>,{pkg,<<"ranch">>,<<"1.7.0">>},0}]}.
+ {<<"ranch">>,{pkg,<<"ranch">>,<<"2.2.0">>},0}]}.
 [
 {pkg_hash,[
- {<<"ranch">>, <<"9583F47160CA62AF7F8D5DB11454068EAA32B56EEADF984D4F46E61A076DF5F2">>}]},
+ {<<"ranch">>, <<"25528F82BC8D7C6152C57666CA99EC716510FE0925CB188172F41CE93117B1B0">>}]},
 {pkg_hash_ext,[
- {<<"ranch">>, <<"59F7501C3A56125B2FC5684C3048FAC9D043C0BF4D173941B12CA927949AF189">>}]}
+ {<<"ranch">>, <<"FA0B99A1780C80218A4197A59EA8D3BDAE32FBFF7E88527D7D8A4787EFF4F8E7">>}]}
 ].

src/mtp_handler.erl

@@ -10,7 +10,7 @@
 -behaviour(ranch_protocol).
 
 %% API
--export([start_link/4, send/2]).
+-export([start_link/3, send/2]).
 -export([hex/1, unhex/1]).
 -export([keys_str/0]).
 
@@ -65,7 +65,7 @@
 
 %% APIs
 
-start_link(Ref, _Socket, Transport, Opts) ->
+start_link(Ref, Transport, Opts) ->
     {ok, proc_lib:spawn_link(?MODULE, ranch_init, [{Ref, Transport, Opts}])}.
 
 keys_str() ->

src/mtproto_proxy_app.erl

@@ -94,21 +94,19 @@ diff_env(NewEnv, OldEnv) ->
 %% @doc List of ranch listeners running mtproto_proxy
 -spec mtp_listeners() -> [tuple()].
 mtp_listeners() ->
-    lists:filter(
-      fun({_Name, Opts}) ->
-              proplists:get_value(protocol, Opts) == mtp_handler
-      end,
-      ranch:info()).
+    maps:to_list(
+      maps:filter(
+        fun(_Name, #{protocol := Protocol}) ->
+                Protocol == mtp_handler
+        end,
+        ranch:info())).
 
 
 %% @doc Currently running listeners in a form of proxy_port()
 -spec running_ports() -> [proxy_port()].
 running_ports() ->
     lists:map(
-      fun({Name, Opts}) ->
-              #{protocol_options := ProtoOpts,
-                ip := Ip,
-                port := Port} = maps:from_list(Opts),
+      fun({Name, #{protocol_options := ProtoOpts, ip := Ip, port := Port}}) ->
               [Name, Secret, AdTag] = ProtoOpts,
               case inet:ntoa(Ip) of
                   {error, einval} ->

test/mtp_test_middle_server.erl

@@ -6,7 +6,7 @@
 -export([start/2,
          stop/1,
          get_rpc_handler_state/1]).
--export([start_link/4,
+-export([start_link/3,
          ranch_init/1]).
 -export([init/1,
          callback_mode/0,
@@ -63,7 +63,7 @@ get_rpc_handler_state(Pid) ->
 
 %% Callbacks
 
-start_link(Ref, _, Transport, Opts) ->
+start_link(Ref, Transport, Opts) ->
     {ok, proc_lib:spawn_link(?MODULE, ranch_init, [{Ref, Transport, Opts}])}.
 
 ranch_init({Ref, Transport, Opts}) ->

test/single_dc_SUITE.erl

@@ -317,11 +317,11 @@ config_change_case({post, Cfg}) ->
     stop_single(Cfg);
 config_change_case(Cfg) when is_list(Cfg) ->
     %% test "max_connections"
-    MaxConnsBefore = [{Listener, proplists:get_value(max_connections, Opts)}
+    MaxConnsBefore = [{Listener, maps:get(max_connections, Opts)}
                       || {Listener, Opts} <- mtproto_proxy_app:mtp_listeners()],
     NewMaxConns = 10,
     ok = mtproto_proxy_app:config_change([{max_connections, NewMaxConns}], [], []),
-    MaxConnsAfter = [{Listener, proplists:get_value(max_connections, Opts)}
+    MaxConnsAfter = [{Listener, maps:get(max_connections, Opts)}
                      || {Listener, Opts} <- mtproto_proxy_app:mtp_listeners()],
     ?assertNotEqual(MaxConnsBefore, MaxConnsAfter),
     ?assert(lists:all(fun({_Listener, MaxConns}) ->