/**
* MySQL Resource - Replication
*
* Replication status, lag monitoring, and GTID information.
*/
import type { MySQLAdapter } from '../MySQLAdapter.js';
import type { ResourceDefinition, RequestContext } from '../../../types/index.js';
export function createReplicationResource(adapter: MySQLAdapter): ResourceDefinition {
return {
uri: 'mysql://replication',
name: 'Replication Status',
title: 'MySQL Replication Status',
description: 'Replication status, lag monitoring, and GTID information',
mimeType: 'application/json',
annotations: {
audience: ['user', 'assistant'],
priority: 0.6
},
handler: async (_uri: string, _context: RequestContext) => {
// Check if this is a replica
let replicaStatus: Record<string, unknown> | null = null;
try {
// Try MySQL 8.0.22+ syntax first
const replicaResult = await adapter.executeQuery('SHOW REPLICA STATUS');
if (replicaResult.rows && replicaResult.rows.length > 0) {
replicaStatus = replicaResult.rows[0] ?? null;
}
} catch {
try {
// Fall back to older syntax
const slaveResult = await adapter.executeQuery('SHOW SLAVE STATUS');
if (slaveResult.rows && slaveResult.rows.length > 0) {
replicaStatus = slaveResult.rows[0] ?? null;
}
} catch {
// Not a replica or no permissions
}
}
// Check if this is a source/master
let sourceStatus: Record<string, unknown> | null = null;
try {
const binlogResult = await adapter.executeQuery('SHOW BINARY LOG STATUS');
if (binlogResult.rows && binlogResult.rows.length > 0) {
sourceStatus = binlogResult.rows[0] ?? null;
}
} catch {
try {
// Fall back to older syntax
const masterResult = await adapter.executeQuery('SHOW MASTER STATUS');
if (masterResult.rows && masterResult.rows.length > 0) {
sourceStatus = masterResult.rows[0] ?? null;
}
} catch {
// Binary logging may be disabled
}
}
// Get GTID info if available
const gtidInfo: Record<string, string> = {};
try {
const gtidResult = await adapter.executeQuery(`
SHOW GLOBAL VARIABLES WHERE Variable_name IN (
'gtid_mode', 'gtid_executed', 'gtid_purged', 'enforce_gtid_consistency'
)
`);
for (const row of gtidResult.rows ?? []) {
gtidInfo[row['Variable_name'] as string] = row['Value'] as string;
}
} catch {
// GTID may not be available
}
// Get connected replicas if this is a source
let replicas: unknown[] = [];
try {
const replicasResult = await adapter.executeQuery('SHOW REPLICAS');
replicas = replicasResult.rows ?? [];
} catch {
try {
const replicasResult = await adapter.executeQuery('SHOW SLAVE HOSTS');
replicas = replicasResult.rows ?? [];
} catch {
// May not have permission or no replicas connected
}
}
// Determine role
let role = 'standalone';
if (replicaStatus) {
role = sourceStatus ? 'replica-source' : 'replica';
} else if (sourceStatus) {
role = 'source';
}
return {
role,
source: sourceStatus ? {
file: sourceStatus['File'],
position: sourceStatus['Position'],
binlog_do_db: sourceStatus['Binlog_Do_DB'],
binlog_ignore_db: sourceStatus['Binlog_Ignore_DB']
} : null,
replica: replicaStatus ? {
source_host: replicaStatus['Source_Host'] ?? replicaStatus['Master_Host'],
source_port: replicaStatus['Source_Port'] ?? replicaStatus['Master_Port'],
io_running: replicaStatus['Replica_IO_Running'] ?? replicaStatus['Slave_IO_Running'],
sql_running: replicaStatus['Replica_SQL_Running'] ?? replicaStatus['Slave_SQL_Running'],
seconds_behind: replicaStatus['Seconds_Behind_Source'] ?? replicaStatus['Seconds_Behind_Master'],
last_error: replicaStatus['Last_Error'],
relay_log_file: replicaStatus['Relay_Log_File'],
relay_log_pos: replicaStatus['Relay_Log_Pos']
} : null,
gtid: gtidInfo,
connected_replicas: replicas
};
}
};
}
