~drizzle-trunk/drizzle/development

/* - mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-

 *  vim:expandtab:shiftwidth=2:tabstop=2:smarttab:

 *

 *  Copyright 2011 Daniel Nichter

 *

 *  This program is free software: you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation, either version 3 of the License, or

 *  (at your option) any later version.

 *

 *  This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#include <config.h>

#include <string>

#include <fcntl.h>

#include <drizzled/item.h>

#include <drizzled/module/option_map.h>

#include <drizzled/session.h>

#include <drizzled/session/times.h>

#include <drizzled/plugin.h>

#include "query_log.h"

using namespace std;

using namespace drizzled;

using namespace plugin;

QueryLog::QueryLog(bool enabled, QueryLoggerFile *logger_file) :

  drizzled::plugin::EventObserver("query_log"),

  sysvar_enabled(enabled),

  _logger_file(logger_file)

{

}

void QueryLog::registerSessionEventsDo(Session &, EventObserverList &observers)

{

  registerEvent(observers, AFTER_STATEMENT);

}

bool QueryLog::observeEventDo(EventData &data)

{

  // Don't log and return successful if...

  if (not sysvar_enabled          // all logging is disabled

      || not sysvar_file_enabled) // or file logging is disabled

    return false;

  switch (data.event) {

  case AFTER_STATEMENT:

    afterStatement((AfterStatementEventData &)data);

    break;

  default:

    fprintf(stderr, "query_log: Unexpected event '%s'\n",

      EventObserver::eventName(data.event));

  }

  return false;

}

bool QueryLog::afterStatement(AfterStatementEventData &data)

{

  Session *session= &data.session;

  // For the moment we're only interestd in queries, not admin

  // command and such.

  if (session->command != COM_QUERY)

    return false;

  // Query end time (microseconds from epoch)

  uint64_t t_mark= session->times.getCurrentTimestamp(false);

  /**

   * Time values, first in microseconds so we can check the thresholds.

   */

  _event.execution_time= session->times.getElapsedTime();

  _event.lock_time= (t_mark - session->times.utime_after_lock);

  _event.session_time= (t_mark - session->times.getConnectMicroseconds());

  /**

   * Check thresholds as soon as possible, return early if possible.

   * This avoid unnecessary work; i.e. don't construct the whole event

   * only to throw it away at the end because it fails a threshold.

   */

  if (   _event.execution_time < sysvar_threshold_execution_time

      || _event.lock_time      < sysvar_threshold_lock_time

      || _event.session_time   < sysvar_threshold_session_time)

    return false;

  /**

   * Convert from microseconds to seconds, e.g. 42 to 0.000042

   * This is done for the user who may read the log.  It's a lot

   * easier to see half a second as 0.5 than 500000.

   */

  _event.execution_time= _event.execution_time * 0.000001;

  _event.lock_time= _event.lock_time * 0.000001;

  _event.session_time= _event.session_time * 0.000001;

  /**

   * Integer values

   */

  _event.session_id= session->getSessionId();

  _event.query_id= session->getQueryId();

  _event.rows_examined= session->examined_row_count;

  _event.rows_sent= session->sent_row_count;

  _event.tmp_tables= session->tmp_table;

  _event.warnings= session->total_warn_count;

  if (   _event.rows_examined < sysvar_threshold_rows_examined

      || _event.rows_sent     < sysvar_threshold_rows_sent

      || _event.tmp_tables    < sysvar_threshold_tmp_tables

      || _event.warnings      < sysvar_threshold_warnings)

    return false;

  /**

   * Boolean values, as strings

   */

  _event.error= session->is_error() ? "true" : "false"; 

  /**

   * String values, may be blank

   */ 

  _event.schema= session->schema()->c_str();

  /**

   * The query string

   */

  _event.query= session->getQueryString()->c_str();

  /**

   * Timestamp values, convert from microseconds from epoch to

   * ISO timestamp like 2002-01-31T10:00:01.123456

   */

  boost::posix_time::ptime t_start= session->times.start_timer();

  _event.ts= boost::posix_time::to_iso_extended_string(t_start);

  // Pass the event to the loggers.

  _logger_file->logEvent((const event_t *)&_event);

  return false; // success

}