@cityssm/mssql-multi-pool/index.js

A simple way to manage connections to multiple SQL Server databases using the Node.js Tedious driver.

import hasPackage from '@cityssm/has-package';
import Debug from 'debug';
import exitHook from 'exit-hook';
import { DEBUG_NAMESPACE } from './debug.config.js';
const debug = Debug(`${DEBUG_NAMESPACE}:index`);
const hasSqlPackage = await hasPackage('msnodesqlv8');
/**
 * The driver that will be used.
 * - msnodesqlv8 on Windows (if available).
 * - tedious or all other operating systems.
 */
export const driver = hasSqlPackage && process.platform === 'win32' ? 'msnodesqlv8' : 'tedious';
debug(`MSSQL driver: ${driver}`);
const mssqlImport = driver === 'msnodesqlv8'
    ? await import('mssql/msnodesqlv8.js')
    : await import('mssql');
const mssql = mssqlImport.default;
const POOLS = new Map();
function getPoolKey(config) {
    return `${config.user ?? ''}@${config.server}/${config.options?.instanceName ?? ''};${config.database ?? ''}`;
}
/**
 * Connect to a MSSQL database.
 * Creates a new connection if the configuration does not match a seen configuration.
 * @param config - MSSQL configuration.
 * @returns A MSSQL connection pool.
 */
export async function connect(config) {
    const poolKey = getPoolKey(config);
    let pool = POOLS.get(poolKey);
    if (!(pool?.connected ?? false)) {
        debug(`New database connection: ${poolKey}`);
        pool = new mssql.ConnectionPool(config);
        await pool.connect();
        POOLS.set(poolKey, pool);
    }
    return pool;
}
/**
 * Release all open connection pools.
 */
export async function releaseAll() {
    debug(`Releasing ${POOLS.size.toString()} pools.`);
    for (const poolKey of POOLS.keys()) {
        debug(`Releasing pool: ${poolKey}`);
        try {
            const pool = POOLS.get(poolKey);
            if (pool !== undefined) {
                await pool.close();
            }
        }
        catch {
            debug('Error closing connections.');
        }
    }
    POOLS.clear();
}
/**
 * Retrieves the number of managed connection pools.
 * @returns The number of pools.
 */
export function getPoolCount() {
    return POOLS.size;
}
/**
 * Initialize shutdown.
 */
debug('Initializing shutdown hooks.');
exitHook(() => {
    debug('Running shutdown hooks.');
    void releaseAll();
});
/*
 * Exports
 */
export default {
    connect,
    driver,
    getPoolCount,
    releaseAll
};
export * as mssql from 'mssql';