WIP List sessions for connection

Display session and link details on the connection page in the Management UI.

Example query:
```
curl -u guest:guest 'http://localhost:15672/api/connections/%5B%3A%3A1%5D%3A49564%20-%3E%20%5B%3A%3A1%5D%3A5672/sessions' | jq .
```

Author: ansd

deps/rabbit/src/rabbit_amqp_reader.erl

@@ -967,7 +967,8 @@ silent_close_delay() ->
 -spec info(rabbit_types:connection(), rabbit_types:info_keys()) ->
     rabbit_types:infos().
 info(Pid, InfoItems) ->
-    case InfoItems -- ?INFO_ITEMS of
+    KnownItems = [sessions | ?INFO_ITEMS],
+    case InfoItems -- KnownItems of
         [] ->
             case gen_server:call(Pid, {info, InfoItems}, infinity) of
                 {ok, InfoList} ->
@@ -1065,6 +1066,8 @@ i(client_properties, #v1{connection = #v1_connection{properties = Props}}) ->
     end;
 i(channels, #v1{tracked_channels = Channels}) ->
     maps:size(Channels);
+i(sessions, #v1{tracked_channels = Val}) ->
+    Val;
 i(channel_max, #v1{connection = #v1_connection{channel_max = Max}}) ->
     Max;
 i(reductions = Item, _State) ->

deps/rabbit/src/rabbit_amqp_session.erl

@@ -92,7 +92,8 @@
          conserve_resources/3,
          check_resource_access/4,
          check_read_permitted_on_topic/4,
-         reset_authz/2
+         reset_authz/2,
+         info/1
         ]).
 
 -export([init/1,
@@ -490,6 +491,8 @@ conserve_resources(Pid, Source, {_, Conserve, _}) ->
 reset_authz(Pid, User) ->
     gen_server:cast(Pid, {reset_authz, User}).
 
+handle_call(infos, _From, State) ->
+    reply(infos(State), State);
 handle_call(Msg, _From, State) ->
     Reply = {error, {not_understood, Msg}},
     reply(Reply, State).
@@ -3702,6 +3705,32 @@ format_status(
               topic_permission_cache => TopicPermissionCache},
     maps:update(state, State, Status).
 
+-spec info(pid()) ->
+    {ok, rabbit_types:infos()} | {error, term()}.
+info(Pid) ->
+    try gen_server:call(Pid, infos) of
+        Infos ->
+            {ok, Infos}
+    catch exit:timeout ->
+              {error, timeout}
+    end.
+
+infos(#state{cfg = #cfg{channel_num = ChannelNum},
+             incoming_window = IncomingWindow,
+             incoming_links = IncomingLinks,
+             outgoing_links = OutgoingLinks}) ->
+    [
+     {channel_number, ChannelNum},
+     {incoming_window, IncomingWindow},
+     {incoming_links, info_incoming_links(IncomingLinks)}
+    ].
+
+info_incoming_links(Links) ->
+    [[
+      {handle, Handle},
+      {snd_settle_mode, SndSettleMode}
+     ]
+     || Handle := #incoming_link{snd_settle_mode = SndSettleMode} <- Links].
 
 unwrap_simple_type(V = {list, _}) ->
     V;

deps/rabbitmq_management/priv/www/js/dispatcher.js

@@ -48,7 +48,8 @@ dispatcher_add(function(sammy) {
             var name = esc(this.params['name']);
             render({'connection': {path:    '/connections/' + name,
                                    options: {ranges: ['data-rates-conn']}},
-                    'channels': '/connections/' + name + '/channels'},
+                    'channels': '/connections/' + name + '/channels',
+                    'sessions': '/connections/' + name + '/sessions'},
                 'connection', '#/connections');
         });
       sammy.del('#/connections', function() {

deps/rabbitmq_management/priv/www/js/global.js

@@ -107,6 +107,11 @@ var ALL_COLUMNS =
                         ['rate-deliver',   'deliver / get',      true],
                         ['rate-redeliver', 'redelivered',        false],
                         ['rate-ack',       'ack',                true]]},
+
+     'sessions' :
+     {'Overview': [],
+      'Session Flow Control': [['incoming-window', 'Incoming window', true]]},
+
      'connections':
      {'Overview': [['container_id', 'Container ID', true],
                    ['user',   'User name', true],

deps/rabbitmq_management/priv/www/js/tmpl/connection.ejs

@@ -84,12 +84,23 @@
 </div>
 </div>
 
+<% if (connection.protocol === "AMQP 1-0") { %>
+<div class="section">
+  <h2 class="updatable" >Sessions (<%=(sessions.length)%>) </h2>
+  <div class="hider updatable">
+    <%= format('sessions-list', {'sessions': sessions}) %>
+  </div>
+</div>
+<% } %>
+
+<% if (connection.protocol === "AMQP 0-9-1") { %>
 <div class="section">
   <h2 class="updatable" >Channels (<%=(channels.length)%>) </h2>
   <div class="hider updatable">
     <%= format('channels-list', {'channels': channels, 'mode': 'connection'}) %>
   </div>
 </div>
+<% } %>
 
 <% if (connection.ssl) { %>
 <div class="section">

deps/rabbitmq_management/priv/www/js/tmpl/sessions-list.ejs

@@ -0,0 +1,32 @@
+<table class="list">
+ <thead>
+
+  <tr>
+    <%= group_heading('sessions', 'Overview', [true]) %>
+    <%= group_heading('sessions', 'Session Flow Control', []) %>
+    <th class="plus-minus"><span class="popup-options-link" title="Click to change columns" type="columns" for="sessions">+/-</span></th>
+  </tr>
+
+  <tr>
+    <th>Channel number</th>
+<% if (show_column('sessions', 'incoming-window')) { %>
+    <th>Incoming Window</th>
+<% } %>
+  </tr>
+
+ </thead>
+
+ <tbody>
+<%
+  for (var i = 0; i < sessions.length; i++) {
+    var session = sessions[i];
+%>
+  <tr>
+    <td class="c"><%= fmt_string(session.channel_number) %></td>
+<% if (show_column('sessions', 'incoming-window')) { %>
+    <td class="c"><%= fmt_string(session.incoming_window) %></td>
+<% } %>
+  </tr>
+  <% } %>
+ </tbody>
+</table>

deps/rabbitmq_management/src/rabbit_mgmt_dispatcher.erl

@@ -132,6 +132,7 @@ dispatcher() ->
      {"/connections/:connection",                              rabbit_mgmt_wm_connection, []},
      {"/connections/username/:username",                       rabbit_mgmt_wm_connection_user_name, []},
      {"/connections/:connection/channels",                     rabbit_mgmt_wm_connection_channels, []},
+     {"/connections/:connection/sessions",                     rabbit_mgmt_wm_connection_sessions, []},
      {"/channels",                                             rabbit_mgmt_wm_channels, []},
      {"/channels/:channel",                                    rabbit_mgmt_wm_channel, []},
      {"/consumers",                                            rabbit_mgmt_wm_consumers, []},

deps/rabbitmq_management/src/rabbit_mgmt_wm_connection_sessions.erl

@@ -0,0 +1,96 @@
+%% This Source Code Form is subject to the terms of the Mozilla Public
+%% License, v. 2.0. If a copy of the MPL was not distributed with this
+%% file, You can obtain one at https://mozilla.org/MPL/2.0/.
+%%
+%% Copyright (c) 2007-2024 Broadcom. All Rights Reserved. The term “Broadcom” refers to Broadcom Inc. and/or its subsidiaries. All rights reserved.
+%%
+
+-module(rabbit_mgmt_wm_connection_sessions).
+
+-export([init/2, to_json/2, content_types_provided/2, is_authorized/2]).
+-export([resource_exists/2]).
+-export([variances/2]).
+
+-include_lib("rabbitmq_management_agent/include/rabbit_mgmt_records.hrl").
+-include_lib("rabbit_common/include/rabbit.hrl").
+
+%%--------------------------------------------------------------------
+
+init(Req, _State) ->
+    {cowboy_rest, rabbit_mgmt_headers:set_common_permission_headers(Req, ?MODULE), #context{}}.
+
+variances(Req, Context) ->
+    {[<<"accept-encoding">>, <<"origin">>], Req, Context}.
+
+content_types_provided(ReqData, Context) ->
+    {rabbit_mgmt_util:responder_map(to_json), ReqData, Context}.
+
+resource_exists(ReqData, Context) ->
+    case conn(ReqData) of
+        not_found ->
+            {false, ReqData, Context};
+        _Conn ->
+            {true, ReqData, Context}
+    end.
+
+to_json(ReqData, Context) ->
+    Conn = conn(ReqData),
+    Protocol = proplists:get_value(protocol, Conn),
+    case Protocol of
+        {1, 0} ->
+            ConnPid = proplists:get_value(pid, Conn),
+            try rabbit_amqp_reader:info(ConnPid, [sessions]) of
+                ConnInfos ->
+                    Sessions = proplists:get_value(sessions, ConnInfos),
+                    SessionPids = maps:values(Sessions),
+                    SessionInfos = session_infos(SessionPids),
+                    rabbit_mgmt_util:reply_list(
+                      SessionInfos, ["channel_number"], ReqData, Context)
+            catch Type:Reason0 ->
+                      Reason = unicode:characters_to_binary(
+                                 lists:flatten(
+                                   io_lib:format(
+                                     "failed to get sessions for connection ~p: ~s ~tp",
+                                     [ConnPid, Type, Reason0]))),
+                      rabbit_mgmt_util:internal_server_error(Reason, ReqData, Context)
+            end;
+        _ ->
+            rabbit_mgmt_util:reply([], ReqData, Context)
+    end.
+
+is_authorized(ReqData, Context) ->
+    try
+        rabbit_mgmt_util:is_authorized_user(ReqData, Context, conn(ReqData))
+    catch
+        {error, invalid_range_parameters, Reason} ->
+            rabbit_mgmt_util:bad_request(iolist_to_binary(Reason), ReqData, Context)
+    end.
+
+%%--------------------------------------------------------------------
+
+conn(Req) ->
+    case rabbit_connection_tracking:lookup(rabbit_mgmt_util:id(connection, Req)) of
+        #tracked_connection{name = Name,
+                            pid = Pid,
+                            protocol = Protocol,
+                            username = Username} ->
+            [{name, Name},
+             {pid, Pid},
+             {protocol, Protocol},
+             {user, Username}];
+        not_found ->
+            not_found
+    end.
+
+session_infos(SessionPids) ->
+    lists:filtermap(
+      fun(Pid) ->
+              case rabbit_amqp_session:info(Pid) of
+                  {ok, Infos} ->
+                      {true, Infos};
+                  {error, Reason} ->
+                      rabbit_log:warning("failed to get infos for session ~p: ~tp",
+                                         [Pid, Reason]),
+                      false
+              end
+      end, SessionPids).