modules/federation: Implement GET /hierarchy.

matrix/matrix.cc

@@ -95,6 +95,7 @@ ircd::m::module_names
 	"federation_event",
 	"federation_get_groups_publicised",
 	"federation_get_missing_events",
+	"federation_hierarchy",
 	"federation_invite",
 	"federation_invite2",
 	"federation_make_join",

modules/Makefile.am

@@ -218,6 +218,7 @@ federation_federation_user_devices_la_SOURCES = federation/user_devices.cc
 federation_federation_user_keys_query_la_SOURCES = federation/user_keys_query.cc
 federation_federation_user_keys_claim_la_SOURCES = federation/user_keys_claim.cc
 federation_federation_rooms_la_SOURCES = federation/rooms.cc
+federation_federation_hierarchy_la_SOURCES = federation/hierarchy.cc
 
 federation_module_LTLIBRARIES = \
 	federation/federation_send.la \
@@ -242,6 +243,7 @@ federation_module_LTLIBRARIES = \
 	federation/federation_user_keys_query.la \
 	federation/federation_user_keys_claim.la \
 	federation/federation_rooms.la \
+	federation/federation_hierarchy.la \
 	###
 
 ###############################################################################

modules/federation/hierarchy.cc

@@ -0,0 +1,174 @@
+// The Construct
+//
+// Copyright (C) The Construct Developers, Authors & Contributors
+// Copyright (C) 2016-2022 Jason Volk <jason@zemos.net>
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice is present in all copies. The
+// full license for this software is available in the LICENSE file.
+
+using namespace ircd;
+
+static m::resource::response
+get__hierarchy(client &client,
+               const m::resource::request &request);
+
+mapi::header
+IRCD_MODULE
+{
+	"Federation 16 :Spaces"
+};
+
+m::resource
+hierarchy_resource
+{
+	"/_matrix/federation/v1/hierarchy/",
+	{
+		"Federation 16 :Spaces hierarchy.",
+		resource::DIRECTORY,
+	}
+};
+
+m::resource::method
+method_get
+{
+	hierarchy_resource, "GET", get__hierarchy,
+	{
+		method_get.VERIFY_ORIGIN
+	}
+};
+
+conf::item<size_t>
+flush_hiwat
+{
+	{ "name",     "ircd.federation.hierarchy.flush.hiwat" },
+	{ "default",  16384L                                  },
+};
+
+conf::item<size_t>
+inaccessible_limit
+{
+	{ "name",     "ircd.federation.hierarchy.inaccessible.limit" },
+	{ "default",  1024L                                          },
+};
+
+m::resource::response
+get__hierarchy(client &client,
+               const m::resource::request &request)
+{
+	using server_acl = m::room::server_acl;
+
+	if(request.parv.size() < 1)
+		throw m::NEED_MORE_PARAMS
+		{
+			"room_id path parameter required"
+		};
+
+	m::room::id::buf room_id
+	{
+		url::decode(room_id, request.parv[0])
+	};
+
+	const m::room room
+	{
+		room_id
+	};
+
+	if(server_acl::enable_read && !server_acl::check(room_id, request.node_id))
+		throw m::ACCESS_DENIED
+		{
+			"You are not permitted by the room's server access control list."
+		};
+
+	if(!visible(room, request.node_id))
+		throw m::ACCESS_DENIED
+		{
+			"You are not permitted to view the room at this event"
+		};
+
+	const bool suggested_only
+	{
+		request.query.get("suggested_only", false)
+	};
+
+	const m::room::state state
+	{
+		room
+	};
+
+	m::resource::response::chunked response
+	{
+		client, http::OK
+	};
+
+	json::stack out
+	{
+		response.buf, response.flusher(), flush_hiwat
+	};
+
+	json::stack::object top
+	{
+		out
+	};
+
+	// room
+	{
+		json::stack::object object
+		{
+			top, "room"
+		};
+
+		m::rooms::summary::get(object, room);
+	}
+
+	// children
+	std::vector<std::string> inaccessible;
+	{
+		json::stack::object object
+		{
+			top, "children"
+		};
+
+		state.for_each("m.space.child", [&object, &request, &inaccessible]
+		(const string_view &, const string_view &state_key, const m::event::idx &)
+		{
+			if(!m::valid(m::id::ROOM, state_key))
+				return true;
+
+			const m::room::id room_id
+			{
+				state_key
+			};
+
+			const bool accessible
+			{
+				true
+				&& m::exists(room_id)
+				&& (!server_acl::enable_read || server_acl::check(room_id, request.node_id))
+				&& visible(room_id, request.node_id)
+			};
+
+			if(!accessible && likely(inaccessible.size() < inaccessible_limit))
+				inaccessible.emplace_back(room_id);
+
+			if(accessible)
+				m::rooms::summary::get(object, room_id);
+
+			return true;
+		});
+	}
+
+	// inaccessible_children
+	{
+		json::stack::array array
+		{
+			top, "inaccessible_children"
+		};
+
+		for(const string_view room_id : inaccessible)
+			array.append(room_id);
+	}
+
+	return response;
+}