Markus Mäkelä f7b8744460 Add more error messages to monitors
When the execution of a query fails, the error reported by the Connector-C
and the server where the query was executed is logged.
2017-08-03 15:42:40 +03:00

254 lines
9.0 KiB
C

#pragma once
/*
* Copyright (c) 2016 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: 2019-07-01
*
* 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.
*/
/**
* @file include/maxscale/monitor.h - The public monitor interface
*/
#include <maxscale/cdefs.h>
#include <mysql.h>
#include <maxscale/config.h>
#include <maxscale/dcb.h>
#include <maxscale/server.h>
MXS_BEGIN_DECLS
struct mxs_monitor;
typedef struct mxs_monitor MXS_MONITOR;
/**
* @verbatim
* The "module object" structure for a backend monitor module
*
* Monitor modules monitor the backend databases that MaxScale connects to.
* The information provided by a monitor is used in routing decisions.
*
* The entry points are:
* startMonitor Called by main to start the monitor
* stopMonitor Called by main to shut down and destroy a monitor
* diagnostics Called for diagnostic output
*
* startMonitor is called to start the monitoring process, it is called on the
* MaxScale main thread and is responsible for creating a thread for the monitor
* itself to run on. This should use the entry points defined in the thread.h
* header file rather than make direct calls to the operating system threading
* libraries. The return from startMonitor is a pointer that will be passed to
* all other monitor API calls.
*
* @endverbatim
*
* @see load_module
*/
typedef struct mxs_monitor_object
{
void *(*startMonitor)(MXS_MONITOR *monitor, const MXS_CONFIG_PARAMETER *params);
void (*stopMonitor)(MXS_MONITOR *monitor);
void (*diagnostics)(DCB *, const MXS_MONITOR *);
} MXS_MONITOR_OBJECT;
/**
* The monitor API version number. Any change to the monitor module API
* must change these versions using the rules defined in modinfo.h
*/
#define MXS_MONITOR_VERSION {3, 0, 0}
/** Monitor's poll frequency */
#define MXS_MON_BASE_INTERVAL_MS 100
#define MXS_MONITOR_RUNNING 1
#define MXS_MONITOR_STOPPING 2
#define MXS_MONITOR_STOPPED 3
#define MXS_MONITOR_DEFAULT_ID 1UL // unsigned long value
#define MAX_MONITOR_USER_LEN 512
#define MAX_MONITOR_PASSWORD_LEN 512
/**
* Monitor state bit mask values
*/
typedef enum
{
MONITOR_STATE_ALLOC = 0x00,
MONITOR_STATE_RUNNING = 0x01,
MONITOR_STATE_STOPPING = 0x02,
MONITOR_STATE_STOPPED = 0x04,
MONITOR_STATE_FREED = 0x08
} monitor_state_t;
/*
* Results of attempt at database connection for monitoring
*/
typedef enum
{
MONITOR_CONN_OK,
MONITOR_CONN_REFUSED,
MONITOR_CONN_TIMEOUT
} mxs_connect_result_t;
/** Monitor events */
typedef enum
{
UNDEFINED_EVENT = 0,
MASTER_DOWN_EVENT = (1 << 0), /**< master_down */
MASTER_UP_EVENT = (1 << 1), /**< master_up */
SLAVE_DOWN_EVENT = (1 << 2), /**< slave_down */
SLAVE_UP_EVENT = (1 << 3), /**< slave_up */
SERVER_DOWN_EVENT = (1 << 4), /**< server_down */
SERVER_UP_EVENT = (1 << 5), /**< server_up */
SYNCED_DOWN_EVENT = (1 << 6), /**< synced_down */
SYNCED_UP_EVENT = (1 << 7), /**< synced_up */
DONOR_DOWN_EVENT = (1 << 8), /**< donor_down */
DONOR_UP_EVENT = (1 << 9), /**< donor_up */
NDB_DOWN_EVENT = (1 << 10), /**< ndb_down */
NDB_UP_EVENT = (1 << 11), /**< ndb_up */
LOST_MASTER_EVENT = (1 << 12), /**< lost_master */
LOST_SLAVE_EVENT = (1 << 13), /**< lost_slave */
LOST_SYNCED_EVENT = (1 << 14), /**< lost_synced */
LOST_DONOR_EVENT = (1 << 15), /**< lost_donor */
LOST_NDB_EVENT = (1 << 16), /**< lost_ndb */
NEW_MASTER_EVENT = (1 << 17), /**< new_master */
NEW_SLAVE_EVENT = (1 << 18), /**< new_slave */
NEW_SYNCED_EVENT = (1 << 19), /**< new_synced */
NEW_DONOR_EVENT = (1 << 20), /**< new_donor */
NEW_NDB_EVENT = (1 << 21), /**< new_ndb */
} mxs_monitor_event_t;
/**
* The linked list of servers that are being monitored by the monitor module.
*/
typedef struct monitor_servers
{
SERVER *server; /**< The server being monitored */
MYSQL *con; /**< The MySQL connection */
bool log_version_err;
int mon_err_count;
unsigned int mon_prev_status;
unsigned int pending_status; /**< Pending Status flag bitmap */
struct monitor_servers *next; /**< The next server in the list */
} MXS_MONITOR_SERVERS;
/**
* Representation of the running monitor.
*/
struct mxs_monitor
{
char *name; /**< The name of the monitor module */
char user[MAX_MONITOR_USER_LEN]; /*< Monitor username */
char password[MAX_MONITOR_PASSWORD_LEN]; /*< Monitor password */
SPINLOCK lock;
MXS_CONFIG_PARAMETER* parameters; /*< configuration parameters */
MXS_MONITOR_SERVERS* databases; /*< List of databases the monitor monitors */
monitor_state_t state; /**< The state of the monitor */
int connect_timeout; /**< Connect timeout in seconds for mysql_real_connect */
int read_timeout; /**< Timeout in seconds to read from the server.
* There are retries and the total effective timeout
* value is three times the option value.
*/
int write_timeout; /**< Timeout in seconds for each attempt to write to the server.
* There are retries and the total effective timeout value is
* two times the option value.
*/
MXS_MONITOR_OBJECT *module; /**< The "monitor object" */
char *module_name; /**< Name of the monitor module */
void *handle; /**< Handle returned from startMonitor */
size_t interval; /**< The monitor interval */
bool created_online; /**< Whether this monitor was created at runtime */
volatile bool server_pending_changes;
/**< Are there any pending changes to a server?
* If yes, the next monitor loop starts early. */
struct mxs_monitor *next; /**< Next monitor in the linked list */
};
static const MXS_ENUM_VALUE mxs_monitor_event_enum_values[] =
{
{"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}
};
/** Default value for the `events` parameter */
static const char MXS_MONITOR_EVENT_DEFAULT_VALUE[] = "master_down,master_up,slave_down,"
"slave_up,server_down,server_up,synced_down,synced_up,donor_down,donor_up,"
"ndb_down,ndb_up,lost_master,lost_slave,lost_synced,lost_donor,lost_ndb,"
"new_master,new_slave,new_synced,new_donor,new_ndb";
bool check_monitor_permissions(MXS_MONITOR* monitor, const char* query);
void monitor_clear_pending_status(MXS_MONITOR_SERVERS *ptr, int bit);
void monitor_set_pending_status(MXS_MONITOR_SERVERS *ptr, int bit);
void servers_status_pending_to_current(MXS_MONITOR *monitor);
void servers_status_current_to_pending(MXS_MONITOR *monitor);
bool mon_status_changed(MXS_MONITOR_SERVERS* mon_srv);
bool mon_print_fail_status(MXS_MONITOR_SERVERS* mon_srv);
mxs_connect_result_t mon_connect_to_db(MXS_MONITOR* mon, MXS_MONITOR_SERVERS *database);
void mon_log_connect_error(MXS_MONITOR_SERVERS* database, mxs_connect_result_t rval);
void lock_monitor_servers(MXS_MONITOR *monitor);
void release_monitor_servers(MXS_MONITOR *monitor);
/**
* @brief Handle state change events
*
* This function should be called by all monitors at the end of each monitoring
* cycle. This will log state changes and execute any scripts that should be executed.
*
* @param monitor Monitor object
* @param script Script to execute or NULL for no script
* @param events Enabled events
*/
void mon_process_state_changes(MXS_MONITOR *monitor, const char *script, uint64_t events);
/**
* @brief Hangup connections to failed servers
*
* Injects hangup events for DCB that are connected to servers that are down.
*
* @param monitor Monitor object
*/
void mon_hangup_failed_servers(MXS_MONITOR *monitor);
/**
* @brief Report query errors
*
* @param db Database where the query failed
*/
void mon_report_query_error(MXS_MONITOR_SERVERS* db);
MXS_END_DECLS