MaxScale/server/core/internal/monitor.h

/*
 * Copyright (c) 2018 MariaDB Corporation Ab
 *
 * Use of this software is governed by the Business Source License included
 * in the LICENSE.TXT file and at www.mariadb.com/bsl11.
 *
 * Change Date: 2022-01-01
 *
 * On the date above, in accordance with the Business Source License, use
 * of this software will be governed by version 2 or later of the General
 * Public License.
 */
#pragma once

/**
 * @file core/maxscale/monitor.h - The private monitor interface
 */

#include <maxscale/monitor.h>
#include "externcmd.h"

MXS_BEGIN_DECLS

#define MON_ARG_MAX 8192

#define DEFAULT_CONNECT_TIMEOUT     3
#define DEFAULT_READ_TIMEOUT        3
#define DEFAULT_WRITE_TIMEOUT       3
#define DEFAULT_CONNECTION_ATTEMPTS 1

#define DEFAULT_MONITOR_INTERVAL 2000   // in milliseconds

/** Default maximum journal age in seconds */
#define DEFAULT_JOURNAL_MAX_AGE 28800

/** Default script execution timeout in seconds */
#define DEFAULT_SCRIPT_TIMEOUT 90

/**
 * Monitor network timeout types
 */
typedef enum
{
    MONITOR_CONNECT_TIMEOUT  = 0,
    MONITOR_READ_TIMEOUT     = 1,
    MONITOR_WRITE_TIMEOUT    = 2,
    MONITOR_CONNECT_ATTEMPTS = 3
} monitor_timeouts_t;

/* Is not really an event as the other values, but is a valid config setting and also the default.
 * Bitmask value matches all events. */
static const MXS_ENUM_VALUE mxs_monitor_event_default_enum = {"all", ~0ULL};
static const MXS_ENUM_VALUE mxs_monitor_event_enum_values[] =
{
    mxs_monitor_event_default_enum,
    {"master_down",                MASTER_DOWN_EVENT },
    {"master_up",                  MASTER_UP_EVENT   },
    {"slave_down",                 SLAVE_DOWN_EVENT  },
    {"slave_up",                   SLAVE_UP_EVENT    },
    {"server_down",                SERVER_DOWN_EVENT },
    {"server_up",                  SERVER_UP_EVENT   },
    {"synced_down",                SYNCED_DOWN_EVENT },
    {"synced_up",                  SYNCED_UP_EVENT   },
    {"donor_down",                 DONOR_DOWN_EVENT  },
    {"donor_up",                   DONOR_UP_EVENT    },
    {"ndb_down",                   NDB_DOWN_EVENT    },
    {"ndb_up",                     NDB_UP_EVENT      },
    {"lost_master",                LOST_MASTER_EVENT },
    {"lost_slave",                 LOST_SLAVE_EVENT  },
    {"lost_synced",                LOST_SYNCED_EVENT },
    {"lost_donor",                 LOST_DONOR_EVENT  },
    {"lost_ndb",                   LOST_NDB_EVENT    },
    {"new_master",                 NEW_MASTER_EVENT  },
    {"new_slave",                  NEW_SLAVE_EVENT   },
    {"new_synced",                 NEW_SYNCED_EVENT  },
    {"new_donor",                  NEW_DONOR_EVENT   },
    {"new_ndb",                    NEW_NDB_EVENT     },
    {NULL}
};

MXS_MONITOR* monitor_create(const char*, const char*, MXS_CONFIG_PARAMETER* params);
void         monitor_destroy(MXS_MONITOR*);

void monitor_start(MXS_MONITOR*, const MXS_CONFIG_PARAMETER*);
void monitor_stop(MXS_MONITOR*);

/**
 * @brief Mark monitor as deactivated
 *
 * A deactivated monitor appears not to exist, as if it had been
 * destroyed.
 *
 * @param monitor
 */
void monitor_deactivate(MXS_MONITOR* monitor);

void monitor_stop_all();
void monitor_start_all();

/**
 * @brief Destroys all monitors. At this point all monitors should
 *        have been stopped.
 *
 * @attn Must only be called in single-thread context at system shutdown.
 */
void monitor_destroy_all();

MXS_MONITOR* monitor_find(const char*);
MXS_MONITOR* monitor_repurpose_destroyed(const char* name, const char* module);

void monitor_show(DCB*, MXS_MONITOR*);
void monitor_show_all(DCB*);

void monitor_list(DCB*);

bool monitor_add_server(MXS_MONITOR* mon, SERVER* server);
void monitor_remove_server(MXS_MONITOR* mon, SERVER* server);
void monitor_add_user(MXS_MONITOR*, const char*, const char*);
void monitor_add_parameters(MXS_MONITOR* monitor, MXS_CONFIG_PARAMETER* params);
bool monitor_remove_parameter(MXS_MONITOR* monitor, const char* key);
void monitor_set_parameter(MXS_MONITOR* monitor, const char* key, const char* value);

void monitor_set_interval(MXS_MONITOR*, unsigned long);
bool monitor_set_network_timeout(MXS_MONITOR*, int, int, const char*);
void monitor_set_journal_max_age(MXS_MONITOR* mon, time_t value);
void monitor_set_script_timeout(MXS_MONITOR* mon, uint32_t value);

/**
 * @brief Serialize a monitor to a file
 *
 * This converts the static configuration of the monitor into an INI format file.
 *
 * @param monitor Monitor to serialize
 * @return True if serialization was successful
 */
bool monitor_serialize(const MXS_MONITOR* monitor);

/**
 * Check if a server is being monitored and return the monitor.
 * @param server Server that is queried
 * @return The monitor watching this server, or NULL if not monitored
 */
MXS_MONITOR* monitor_server_in_use(const SERVER* server);

/**
 * Launch a script
 *
 * @param mon     Owning monitor
 * @param ptr     The server which has changed state
 * @param script  Script to execute
 * @param timeout Timeout in seconds for the script
 *
 * @return Return value of the executed script or -1 on error
 */
int monitor_launch_script(MXS_MONITOR* mon, MXS_MONITORED_SERVER* ptr, const char* script, uint32_t timeout);

/**
 * Launch a command
 *
 * @param mon  Owning monitor
 * @param ptr  The server which has changed state
 * @param cmd  The command to execute.
 *
 * @note All default script variables will be replaced.
 *
 * @return Return value of the executed script or -1 on error.
 */
int monitor_launch_command(MXS_MONITOR* mon, MXS_MONITORED_SERVER* ptr, EXTERNCMD* cmd);

MXS_END_DECLS