static void test_cache_timestamp(session &sess)
{
	argument_data data("this is a timestamp test");

	key k("this is a timestamp test key");
	sess.transform(k);

	dnet_io_control ctl;
	memset(&ctl, 0, sizeof(ctl));

	ctl.data = data.data();

	dnet_current_time(&ctl.io.timestamp);
	ctl.io.flags = DNET_IO_FLAGS_CACHE;
	ctl.io.start = 5;
	ctl.io.size = data.size();

	memcpy(&ctl.id, &k.id(), sizeof(dnet_id));
	ctl.fd = -1;

	ELLIPTICS_REQUIRE(write_result, sess.write_data(ctl));

	sleep(ctl.io.start + 2);

	ELLIPTICS_REQUIRE(read_result, sess.read_data(k, 0, 0));
	auto io = read_result.get_one().io_attribute();

	BOOST_REQUIRE_EQUAL(io->timestamp.tsec, ctl.io.timestamp.tsec);
	BOOST_REQUIRE_EQUAL(io->timestamp.tnsec, ctl.io.timestamp.tnsec);
}

async_result<T>::async_result(const session &sess) : m_data(std::make_shared<data>())
{
	m_data->filter = sess.get_filter();
	m_data->checker = sess.get_checker();
	m_data->policy = sess.get_exceptions_policy();
	m_data->error_handler = sess.get_error_handler();
}

static void test_direct_backend(session &sess)
{
	const key id = std::string("direct-backend-test");
	sess.set_groups({ 0 });
	const std::string first_str = "first-data";
	const std::string second_str = "second-data";

	server_node &node = global_data->nodes.front();

	session first = sess.clone();
	first.set_direct_id(node.remote(), 0);

	session second = sess.clone();
	second.set_direct_id(node.remote(), 3);

	ELLIPTICS_REQUIRE(async_first_write, first.write_data(id, first_str, 0));
	ELLIPTICS_REQUIRE(async_second_write, second.write_data(id, second_str, 0));

	ELLIPTICS_REQUIRE(async_first_read, first.read_data(id, 0, 0));
	read_result_entry first_read = async_first_read.get_one();
	BOOST_REQUIRE_EQUAL(first_read.file().to_string(), first_str);
	BOOST_REQUIRE_EQUAL(first_read.command()->backend_id, 0);

	ELLIPTICS_REQUIRE(async_second_read, second.read_data(id, 0, 0));
	read_result_entry second_read = async_second_read.get_one();
	BOOST_REQUIRE_EQUAL(second_read.file().to_string(), second_str);
	BOOST_REQUIRE_EQUAL(second_read.command()->backend_id, 3);
}

static void test_set_backend_ids_for_disabled(session &sess)
{
	server_node &node = global_data->nodes.back();

	auto ids = generate_ids(16);

	ELLIPTICS_REQUIRE(async_set_result, sess.set_backend_ids(node.remote(), 4, ids));

	backend_status_result_entry result = async_set_result.get_one();
	BOOST_REQUIRE(result.is_valid());
	BOOST_REQUIRE_EQUAL(result.count(), 1);

	dnet_backend_status *status = result.backend(0);
	BOOST_REQUIRE_EQUAL(status->backend_id, 4);
	BOOST_REQUIRE_EQUAL(status->state, DNET_BACKEND_DISABLED);

	ELLIPTICS_REQUIRE(async_enable_result, sess.enable_backend(node.remote(), 4));

	// Wait 0.1 secs to ensure that route list was changed
	usleep(100 * 1000);

	auto route_ids = backend_ids(sess, node.remote(), 4);
	BOOST_REQUIRE_EQUAL(ids.size(), route_ids.size());
	BOOST_REQUIRE(compare_ids(ids, route_ids));
}

static void test_cache_overflow(session &sess)
{
	ioremap::cache::cache_manager *cache = (ioremap::cache::cache_manager*) global_data->nodes[0].get_native()->cache;
	const size_t cache_size = cache->cache_size();
	const size_t cache_pages_number = cache->cache_pages_number();
	argument_data data("0");

	cache->clear();
	size_t record_size = 0;
	{
		ELLIPTICS_REQUIRE(write_result, sess.write_cache(key(std::string("0")), data, 3000));
		const auto& stats = cache->get_total_cache_stats();
		record_size = stats.size_of_objects;
	}

	size_t records_number = (cache_size / cache_pages_number / record_size) * 10;
	for (size_t id = 1; id < records_number; ++id) {
		ELLIPTICS_REQUIRE(write_result, sess.write_cache(key(boost::lexical_cast<std::string>(id)), data, 3000));
		const auto& stats = cache->get_total_cache_stats();

		size_t total_pages_sizes = 0;
		for (size_t i = 0; i < stats.pages_sizes.size(); ++i) {
			total_pages_sizes += stats.pages_sizes[i];

//			BOOST_REQUIRE_LE(stats.pages_sizes[i], stats.pages_max_sizes[i]);
		}

//		BOOST_REQUIRE_LE(stats.size_of_objects, cache_size);
//		BOOST_REQUIRE_EQUAL(stats.size_of_objects, total_pages_sizes);
	}
}

static void test_cache_records_sizes(session &sess, const nodes_data *setup)
{
	dnet_node *node = setup->nodes[0].get_native();
	dnet_backend_io *backend_io = dnet_get_backend_io(node->io, 0);
	ioremap::cache::cache_manager *cache = reinterpret_cast<ioremap::cache::cache_manager *>(backend_io->cache);
	const size_t cache_size = cache->cache_size();
	const size_t cache_pages_number = cache->cache_pages_number();
	argument_data data("0");

	cache->clear();
	size_t record_size = 0;
	{
		ELLIPTICS_REQUIRE(write_result, sess.write_cache(key(boost::lexical_cast<std::string>(0)), data, 3000));
		auto stats = cache->get_total_cache_stats();
		record_size = stats.size_of_objects;
		BOOST_REQUIRE_EQUAL(stats.number_of_objects, 1);
	}

	size_t records_number = cache_size / cache_pages_number / record_size - 5;
	for (size_t id = 1; id < records_number; ++id) {
		ELLIPTICS_REQUIRE(write_result,
		                  sess.write_cache(key(boost::lexical_cast<std::string>(id)), data, 3000));
		auto stats = cache->get_total_cache_stats();

		size_t total_pages_sizes = 0;
		for (size_t i = 0; i < stats.pages_sizes.size(); ++i) {
			total_pages_sizes += stats.pages_sizes[i];
		}

		BOOST_REQUIRE_EQUAL(stats.number_of_objects * record_size, stats.size_of_objects);
		BOOST_REQUIRE_EQUAL(stats.number_of_objects, id + 1);
		BOOST_REQUIRE_EQUAL(stats.size_of_objects, total_pages_sizes);
	}
}

 table_creator_2(session & sql)
         : tests::table_creator_base(sql)
 {
     sql  << "create table soci_test(\"num_float\" float, \"num_int\" integer, "
     "\"name\" varchar(20), \"sometime\" timestamp, \"chr\" char)";
     sql.commit();
     sql.begin();
 }

 table_creator_1(session & sql)
         : tests::table_creator_base(sql)
 {
     sql << "create table soci_test(id integer, val integer, c char, "
     "str varchar(20), sh smallint, ul decimal(9,0), d double precision, "
     "tm timestamp, i1 integer, i2 integer, i3 integer, name varchar(20))";
     sql.commit();
     sql.begin();
 }

 table_creator_3(session & sql)
         : tests::table_creator_base(sql)
 {
     // CommonTest uses lower-case column names,
     // so we need to enforce such names here.
     // That's why column names are enclosed in ""
     sql << "create table soci_test(\"name\" varchar(100) not null, "
     "\"phone\" varchar(15))";
     sql.commit();
     sql.begin();
 }

static void init_application_impl(session &sess, const std::string &app_name, nodes_data &data)
{
    node_info info = node_info::create(data, sess.get_groups());

    ELLIPTICS_REQUIRE(exec_result, sess.exec(NULL, app_name + "@init", info.pack()));

    sync_exec_result result = exec_result;
    BOOST_REQUIRE_EQUAL(result.size(), data.nodes.size());
    for (auto it = result.begin(); it != result.end(); ++it)
        BOOST_REQUIRE_EQUAL(it->context().data().to_string(), "inited");
}

static void test_error_message(session &s, const std::string &id, int err)
{
	s.set_filter(filters::all);

	ELLIPTICS_REQUIRE_ERROR(read_result, s.read_data(id, 0, 0), err);

	sync_read_result sync_result = read_result.get();

	BOOST_REQUIRE(sync_result.size() > 0);

	read_result_entry entry = sync_result[0];

	BOOST_REQUIRE_EXCEPTION(entry.io_attribute(), not_found_error, test_error_check_exception);
}

void init_application_impl(session &sess, const std::string &app_name, const nodes_data *setup)
{
	sess.set_timeout(600);
	auto log = sess.get_logger();
	DNET_LOG_INFO(log, "Sending @init");

	node_info info = node_info_create(setup, sess.get_groups());

	ELLIPTICS_REQUIRE(exec_result, sess.exec(NULL, app_name + "@init", info.pack()));

	sync_exec_result result = exec_result;
	BOOST_REQUIRE_EQUAL(result.size(), setup->nodes.size());
	for (auto it = result.begin(); it != result.end(); ++it)
		BOOST_REQUIRE_EQUAL(it->context().data().to_string(), "inited");
}

statement_impl::statement_impl(session & s)
    : session_(s), refCount_(1), row_(0),
      fetchSize_(1), initialFetchSize_(1),
      alreadyDescribed_(false)
{
    backEnd_ = s.make_statement_backend();
}

	torrent_handle add_magnet_uri(session& ses, std::string const& uri
		, add_torrent_params p)
	{
		std::string name;
		std::string tracker;

		boost::optional<std::string> display_name = url_has_argument(uri, "dn");
		if (display_name) name = unescape_string(display_name->c_str());
		boost::optional<std::string> tracker_string = url_has_argument(uri, "tr");
		if (tracker_string) tracker = unescape_string(tracker_string->c_str());
	
		boost::optional<std::string> btih = url_has_argument(uri, "xt");
		if (!btih) return torrent_handle();

		if (btih->compare(0, 9, "urn:btih:") != 0) return torrent_handle();

		sha1_hash info_hash;
		if (btih->size() == 40 + 9) info_hash = boost::lexical_cast<sha1_hash>(btih->substr(9));
		else info_hash.assign(base32decode(btih->substr(9)));

		if (!tracker.empty()) p.tracker_url = tracker.c_str();
		p.info_hash = info_hash;
		if (!name.empty()) p.name = name.c_str();
		return ses.add_torrent(p);
	}

	torrent_handle add_magnet_uri(session& ses, std::string const& uri
		, std::string const& save_path
		, storage_mode_t storage_mode
		, bool paused
		, storage_constructor_type sc
		, void* userdata)
	{
		std::string name;
		std::string tracker;

		error_code ec;
		std::string display_name = url_has_argument(uri, "dn");
		if (!display_name.empty()) name = unescape_string(display_name.c_str(), ec);
		std::string tracker_string = url_has_argument(uri, "tr");
		if (!tracker_string.empty()) tracker = unescape_string(tracker_string.c_str(), ec);
	
		std::string btih = url_has_argument(uri, "xt");
		if (btih.empty()) return torrent_handle();

		if (btih.compare(0, 9, "urn:btih:") != 0) return torrent_handle();

		sha1_hash info_hash;
		if (btih.size() == 40 + 9) from_hex(&btih[9], 40, (char*)&info_hash[0]);
		else info_hash.assign(base32decode(btih.substr(9)));

		return ses.add_torrent(tracker.empty() ? 0 : tracker.c_str(), info_hash
			, name.empty() ? 0 : name.c_str(), save_path, entry()
			, storage_mode, paused, sc, userdata);
	}

	torrent_handle add_magnet_uri_deprecated(session& ses, std::string const& uri
		, add_torrent_params p, error_code& ec)
	{
		parse_magnet_uri(uri, p, ec);
		if (ec) return torrent_handle();
		return ses.add_torrent(p, ec);
	}

	torrent_handle add_magnet_uri(session& ses, std::string const& uri
		, add_torrent_params p, error_code& ec)
	{
		std::string name;
		std::string tracker;

		error_code e;
		boost::optional<std::string> display_name = url_has_argument(uri, "dn");
		if (display_name) name = unescape_string(display_name->c_str(), e);
		boost::optional<std::string> tracker_string = url_has_argument(uri, "tr");
		if (tracker_string) tracker = unescape_string(tracker_string->c_str(), e);
	
		boost::optional<std::string> btih = url_has_argument(uri, "xt");
		if (!btih)
		{
			ec = error_code(errors::missing_info_hash_in_uri, libtorrent_category);
			return torrent_handle();
		}

		if (btih->compare(0, 9, "urn:btih:") != 0)
		{
			ec = error_code(errors::missing_info_hash_in_uri, libtorrent_category);
			return torrent_handle();
		}

		sha1_hash info_hash;
		if (btih->size() == 40 + 9) from_hex(&(*btih)[9], 40, (char*)&info_hash[0]);
		else info_hash.assign(base32decode(btih->substr(9)));

		if (!tracker.empty()) p.tracker_url = tracker.c_str();
		p.info_hash = info_hash;
		if (!name.empty()) p.name = name.c_str();
		return ses.add_torrent(p, ec);
	}

	torrent_handle add_magnet_uri(session& ses, std::string const& uri
		, std::string const& save_path
		, storage_mode_t storage_mode
		, bool paused
		, storage_constructor_type sc
		, void* userdata)
	{
		add_torrent_params params(sc);
		params.storage_mode = storage_mode;
		params.userdata = userdata;
		params.save_path = save_path;

		if (paused) params.flags |= add_torrent_params::flag_paused;
		else params.flags &= ~add_torrent_params::flag_paused;

		error_code ec;
		std::string display_name = url_has_argument(uri, "dn");
		if (!display_name.empty()) params.name = unescape_string(display_name.c_str(), ec);
		std::string tracker_string = url_has_argument(uri, "tr");
		if (!tracker_string.empty()) params.trackers.push_back(unescape_string(tracker_string.c_str(), ec));
	
		std::string btih = url_has_argument(uri, "xt");
		if (btih.empty()) return torrent_handle();

		if (btih.compare(0, 9, "urn:btih:") != 0) return torrent_handle();

		if (btih.size() == 40 + 9) from_hex(&btih[9], 40, (char*)&params.info_hash[0]);
		else params.info_hash.assign(base32decode(btih.substr(9)));

		return ses.add_torrent(params);
	}

/*
 * Multiple writes with same key must be processed in the same order as
 * they were initiated by client.
 *
 * Following test checks this mechanics by calling write_cas() with data containing
 * counter that is incremented after every write_cas() and checking that previosly stored
 * counter is one unit less than current counter. Also this test writes multiple different
 * keys (with repetitions) in different order, thereby modelling real workload case.
 */
static void test_write_order_execution(session &sess)
{
	const int num_write_repetitions = 5;
	const int num_different_keys = 10;
	std::vector<std::pair<key, int>> keys;
	for (int i = 0; i < num_different_keys; ++i) {
		key id(std::to_string(static_cast<unsigned long long>(i)));
		for (int j = 0; j < num_write_repetitions; ++j) {
			keys.push_back(std::make_pair(id, i));
		}
	}

	std::unique_ptr<async_write_result[]> results(new async_write_result[keys.size()]);
	dnet_id old_csum;

	const int num_iterations = 30;
	for (int i = 0; i < num_iterations; ++i) {
		// every key is associated with counter, which is initialized by zero
		std::vector<int> write_counter(num_different_keys, 0);

		std::random_shuffle(keys.begin(), keys.end());

		for (size_t j = 0; j < keys.size(); ++j) {
			// increment counter associated with key identified by key_id
			const int key_id = keys[j].second;
			const int new_value = write_counter[key_id]++;
			if (new_value > 0) {
				const int prev_value = new_value - 1;
				memset(&old_csum, 0, sizeof(old_csum));
				sess.transform(std::to_string(static_cast<unsigned long long>(prev_value)), old_csum);
				results[j] = std::move(sess.write_cas(keys[j].first, std::to_string(static_cast<unsigned long long>(new_value)), old_csum, 0));
			} else {
				// first write
				results[j] = std::move(sess.write_data(keys[j].first, std::to_string(static_cast<unsigned long long>(new_value)), 0));
			}
		}

		for (size_t j = 0; j < keys.size(); ++j) {
			results[j].wait();
			const int err = results[j].error().code();
			BOOST_REQUIRE_MESSAGE(err == 0,
					      "write_cas() failed (err=" + std::to_string(static_cast<unsigned long long>(err)) + "): "
					      "multiple consecutive writes are executed out-of-order "
					      "or overlapped. Oplock mechanism of backend's request queue is broken.");
		}
	}
}

static void start_application(session &sess, const std::string &app_name)
{
    key key_id = app_name;
    key_id.transform(sess);
    dnet_id id = key_id.id();

    ELLIPTICS_REQUIRE(result, sess.exec(&id, app_name + "@start-task", data_pointer()));
}