Add option to include sideband info of confirmed blocks in websocket messages (#3698)

Co-authored-by: gr0vity <gr0vity.dev@gmail.com>

nano/core_test/websocket.cpp

@@ -382,6 +382,75 @@ TEST (websocket, confirmation_options_votes)
 	}
 }
 
+TEST (websocket, confirmation_options_sideband)
+{
+	nano::system system;
+	nano::node_config config (nano::get_available_port (), system.logging);
+	config.websocket_config.enabled = true;
+	config.websocket_config.port = nano::get_available_port ();
+	auto node1 (system.add_node (config));
+
+	std::atomic<bool> ack_ready{ false };
+	auto task1 = ([&ack_ready, config, &node1] () {
+		fake_websocket_client client (config.websocket_config.port);
+		client.send_message (R"json({"action": "subscribe", "topic": "confirmation", "ack": "true", "options": {"confirmation_type": "active_quorum", "include_block": "false", "include_sideband_info": "true"}})json");
+		client.await_ack ();
+		ack_ready = true;
+		EXPECT_EQ (1, node1->websocket_server->subscriber_count (nano::websocket::topic::confirmation));
+		return client.get_response ();
+	});
+	auto future1 = std::async (std::launch::async, task1);
+
+	ASSERT_TIMELY (10s, ack_ready);
+
+	// Confirm a state block for an in-wallet account
+	system.wallet (0)->insert_adhoc (nano::dev::genesis_key.prv);
+	nano::keypair key;
+	auto balance = nano::dev::constants.genesis_amount;
+	auto send_amount = node1->config.online_weight_minimum.number () + 1;
+	nano::block_hash previous (node1->latest (nano::dev::genesis_key.pub));
+	{
+		nano::state_block_builder builder;
+		balance -= send_amount;
+		auto send = builder
+					.account (nano::dev::genesis_key.pub)
+					.previous (previous)
+					.representative (nano::dev::genesis_key.pub)
+					.balance (balance)
+					.link (key.pub)
+					.sign (nano::dev::genesis_key.prv, nano::dev::genesis_key.pub)
+					.work (*system.work.generate (previous))
+					.build_shared ();
+
+		node1->process_active (send);
+		previous = send->hash ();
+	}
+
+	ASSERT_TIMELY (5s, future1.wait_for (0s) == std::future_status::ready);
+
+	auto response1 = future1.get ();
+	ASSERT_TRUE (response1);
+	boost::property_tree::ptree event;
+	std::stringstream stream;
+	stream << response1.get ();
+	boost::property_tree::read_json (stream, event);
+	ASSERT_EQ (event.get<std::string> ("topic"), "confirmation");
+	try
+	{
+		boost::property_tree::ptree sideband_info = event.get_child ("message.sideband");
+		// Check if height and local_timestamp are present
+		ASSERT_EQ (1, sideband_info.count ("height"));
+		ASSERT_EQ (1, sideband_info.count ("local_timestamp"));
+		// Make sure height and local_timestamp are non-zero.
+		ASSERT_NE ("0", sideband_info.get<std::string> ("height"));
+		ASSERT_NE ("0", sideband_info.get<std::string> ("local_timestamp"));
+	}
+	catch (std::runtime_error const & ex)
+	{
+		FAIL () << ex.what ();
+	}
+}
+
 // Tests updating options of block confirmations
 TEST (websocket, confirmation_options_update)
 {

nano/node/websocket.cpp

@@ -26,6 +26,7 @@ nano::websocket::confirmation_options::confirmation_options (boost::property_tre
 	include_block = options_a.get<bool> ("include_block", true);
 	include_election_info = options_a.get<bool> ("include_election_info", false);
 	include_election_info_with_votes = options_a.get<bool> ("include_election_info_with_votes", false);
+	include_sideband_info = options_a.get<bool> ("include_sideband_info", false);
 
 	confirmation_types = 0;
 	auto type_l (options_a.get<std::string> ("confirmation_type", "all"));
@@ -766,6 +767,14 @@ nano::websocket::message nano::websocket::message_builder::block_confirmed (std:
 		message_node_l.add_child ("block", block_node_l);
 	}
 
+	if (options_a.get_include_sideband_info ())
+	{
+		boost::property_tree::ptree sideband_node_l;
+		sideband_node_l.add ("height", std::to_string (block_a->sideband ().height));
+		sideband_node_l.add ("local_timestamp", std::to_string (block_a->sideband ().timestamp));
+		message_node_l.add_child ("sideband", sideband_node_l);
+	}
+
 	message_l.contents.add_child ("message", message_node_l);
 
 	return message_l;

nano/node/websocket.hpp

@@ -174,6 +174,12 @@ namespace websocket
 			return include_election_info_with_votes;
 		}
 
+		/** Returns whether or not to include sideband info */
+		bool get_include_sideband_info () const
+		{
+			return include_sideband_info;
+		}
+
 		static constexpr uint8_t const type_active_quorum = 1;
 		static constexpr uint8_t const type_active_confirmation_height = 2;
 		static constexpr uint8_t const type_inactive = 4;
@@ -187,6 +193,7 @@ namespace websocket
 		boost::optional<nano::logger_mt &> logger;
 		bool include_election_info{ false };
 		bool include_election_info_with_votes{ false };
+		bool include_sideband_info{ false };
 		bool include_block{ true };
 		bool has_account_filtering_options{ false };
 		bool all_local_accounts{ false };