scylladb/tracing/trace_state.cc

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/*
 * Copyright (C) 2016 ScyllaDB
 *
 * Modified by ScyllaDB
 */

/*
 * This file is part of Scylla.
 *
 * Scylla is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Scylla is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Scylla.  If not, see <http://www.gnu.org/licenses/>.
 */
#include <chrono>
#include "tracing/trace_state.hh"
#include "tracing/trace_keyspace_helper.hh"
#include "service/storage_proxy.hh"
#include "to_string.hh"
#include "timestamp.hh"

namespace tracing {

logging::logger trace_state_logger("trace_state");

void trace_state::build_parameters_map() {
    if (!_params_ptr) {
        return;
    }

    auto& params_map = _records->session_rec.parameters;
    params_values& vals = *_params_ptr;

    if (vals.batchlog_endpoints) {
        params_map.emplace("batch_endpoints", join(sstring(","),  *vals.batchlog_endpoints | boost::adaptors::transformed([](gms::inet_address ep) {return seastar::format("/{}", ep);})));
    }

    if (vals.cl) {
        params_map.emplace("consistency_level", seastar::format("{}", *vals.cl));
    }

    if (vals.serial_cl) {
        params_map.emplace("serial_consistency_level", seastar::format("{}", *vals.serial_cl));
    }

    if (vals.page_size) {
        params_map.emplace("page_size", seastar::format("{:d}", *vals.page_size));
    }

    if (vals.query) {
        params_map.emplace("query", *vals.query);
    }

    if (vals.user_timestamp) {
        params_map.emplace("user_timestamp", seastar::format("{:d}", *vals.user_timestamp));
    }
}

trace_state::~trace_state() {
    if (!is_primary() && is_in_state(state::background)) {
        trace_state_logger.error("Secondary session is in a background state! session_id: {}", session_id());
    }

    stop_foreground_and_write();
    _local_tracing_ptr->end_session();

    trace_state_logger.trace("{}: destructing", session_id());
}

void trace_state::stop_foreground_and_write() noexcept {
    // Do nothing if state hasn't been initiated
    if (is_in_state(state::inactive)) {
        return;
    }

    if (is_in_state(state::foreground)) {
        auto e = elapsed();
        _records->do_log_slow_query = should_log_slow_query(e);

        if (is_primary()) {
            // We don't account the session_record event when checking a limit
            // of maximum events per session because there may be only one such
            // event and we don't want to cripple the primary session by
            // "stealing" one trace() event from it.
            //
            // We do want to account them however. If for instance there are a
            // lot of tracing sessions that only open itself and then do nothing
            // - they will create a lot of session_record events and we do want
            // to handle this case properly.
            _records->consume_from_budget();

            _records->session_rec.elapsed = e;

            // build_parameters_map() may throw. We don't want to record the
            // session's record in this case since its data may be incomplete.
            // These events should be really rare however, therefore we don't
            // want to optimize this flow (e.g. rollback the corresponding
            // events' records that have already been sent to I/O).
            if (should_write_records()) {
                try {
                    build_parameters_map();
                } catch (...) {
                    // Bump up an error counter, drop any pending records and
                    // continue
                    ++_local_tracing_ptr->stats.trace_errors;
                    _records->drop_records();
                }
            }
        }

        set_state(state::background);
    }

    trace_state_logger.trace("{}: Current records count is {}",  session_id(), _records->size());

    if (should_write_records()) {
        _local_tracing_ptr->write_session_records(_records, write_on_close());
    } else {
        _records->drop_records();
    }
}
}