feat(archive): month snapshots on the same node, drop extra-node and HTML /view.

Fixes EventHub/EventHubBack#76

Co-authored-by: Cursor <cursoragent@cursor.com>

test/unit/eh_test_support.erl

@@ -99,7 +99,8 @@ ensure_indexes(Tables) when is_list(Tables) ->
     {push_subscription, [user_id, endpoint]},
     {auth_session, [family_id, subject_id]},
     {report, [resolved_by]},
-    {ticket, [assigned_to]}
+    {ticket, [assigned_to]},
+    {month_snapshot, [calendar_id, year_month]}
   ]),
   ok.
 
@@ -204,7 +205,9 @@ table_opts(node_metric) ->
   [{ram_copies, [node()]}, {local_content, true},
    {attributes, record_info(fields, node_metric)}];
 table_opts(schema_migration) ->
-  [{ram_copies, [node()]}, {attributes, record_info(fields, schema_migration)}].
+  [{ram_copies, [node()]}, {attributes, record_info(fields, schema_migration)}];
+table_opts(month_snapshot) ->
+  [{ram_copies, [node()]}, {attributes, record_info(fields, month_snapshot)}].
 
 %%%===================================================================
 %%% Domain seeds

test/unit/logic_month_archive_tests.erl

@@ -0,0 +1,43 @@
+-module(logic_month_archive_tests).
+-include_lib("eunit/include/eunit.hrl").
+-include("records.hrl").
+
+-define(TABLES, [event, month_snapshot, booking, calendar]).
+-define(CAL, <<"cal_arch_1">>).
+
+setup() ->
+  eh_test_support:start_mnesia(),
+  eh_test_support:ensure_tables(?TABLES),
+  Tmp = filename:join("/tmp", "eh_arch_" ++ integer_to_list(erlang:unique_integer([positive]))),
+  ok = filelib:ensure_dir(filename:join(Tmp, "dummy")),
+  true = os:putenv("UPLOAD_DIR", Tmp),
+  ok.
+
+cleanup(_) ->
+  eh_test_support:clear_tables(?TABLES),
+  eh_test_support:delete_tables(?TABLES),
+  eh_test_support:stop_mnesia(),
+  ok.
+
+logic_month_archive_test_() ->
+  {foreach, fun setup/0, fun cleanup/1, [
+    {"closed month is not writable", fun test_assert_writable/0},
+    {"snapshot removes hot event and serves json", fun test_snapshot_roundtrip/0}
+  ]}.
+
+test_assert_writable() ->
+  {{Y, M, _}, _} = calendar:universal_time(),
+  ?assertEqual(ok, logic_month_archive:assert_writable({{Y, M, 15}, {12, 0, 0}})),
+  ?assertEqual({error, archived},
+               logic_month_archive:assert_writable({{2020, 1, 10}, {12, 0, 0}})).
+
+test_snapshot_roundtrip() ->
+  {ok, Ev} = core_event:create(?CAL, <<"old">>, {{2020, 6, 10}, {10, 0, 0}}, 60),
+  ok = logic_month_archive:snapshot_month(?CAL, 2020, 6),
+  ?assertEqual([], mnesia:dirty_read(event, Ev#event.id)),
+  Json = logic_month_archive:events_json_in_range(
+           ?CAL, {{2020, 6, 1}, {0, 0, 0}}, {{2020, 6, 30}, {23, 59, 59}}),
+  ?assertEqual(1, length(Json)),
+  [Map] = Json,
+  Id = maps:get(<<"id">>, Map, maps:get(id, Map, undefined)),
+  ?assertEqual(Ev#event.id, Id).

test/unit/migration_engine_tests.erl

@@ -18,7 +18,8 @@
   "20260814193000_waitlist_entry",
   "20260815200000_push_subscription",
   "20260815220000_calendar_share_invite",
-  "20260816180000_auth_session_device"
+  "20260816180000_auth_session_device",
+  "20260817140000_month_snapshot"
 ]).
 
 setup() ->