MCP Server Starter

// src/db/providers/mssql.ts import mssql from 'mssql'; import type { DB } from '../provider.js'; export default function createMssqlDb(): DB { const connectionString = process.env.DATABASE_URL!; let pool: mssql.ConnectionPool | null = null; let connectPromise: Promise<mssql.ConnectionPool> | null = null; async function getPool(): Promise<mssql.ConnectionPool> { if (pool && pool.connected) return pool; if (!connectPromise) { connectPromise = new mssql.ConnectionPool(connectionString) .connect() .then(p => { pool = p; return p; }) .catch(err => { connectPromise = null; throw err; }); } return connectPromise; } return { dialect: 'mssql', async query(text, params?: any) { const p = await getPool(); const req = p.request(); // Support both array and object parameters if (params) { if (Array.isArray(params)) { // Accept either positional values OR {name, value} objects let posIndex = 0; for (const v of params) { if (v && typeof v === 'object' && 'name' in v) { req.input(String((v as any).name), (v as any).value as any); } else { req.input(`p${++posIndex}`, v as any); } } } else if (typeof params === 'object') { for (const [k, v] of Object.entries(params)) { req.input(k, v as any); } } } const result = await req.query(text); const rows = result.recordset ?? []; return { rows, rowCount: Array.isArray(rows) ? rows.length : 0 }; }, async close() { try { await pool?.close(); } finally { pool = null; connectPromise = null; } }, }; }