dj-postgres-mcp/build/features/database/tools/execute-query.js

Model Context Protocol (MCP) server for PostgreSQL database operations with centralized configuration via dj-config-mcp

import { QueryExecutor } from '../QueryExecutor.js';
import { ManagedError, ErrorCodes } from '../../shared/errors.js';
import { Client } from 'pg';
export function createExecuteQueryTool() {
    return {
        name: 'execute_query',
        description: 'Execute a SQL query against the configured PostgreSQL database',
        inputSchema: {
            type: 'object',
            properties: {
                query: {
                    type: 'string',
                    description: 'SQL query to execute'
                },
                params: {
                    type: 'array',
                    description: 'Query parameters for parameterized queries',
                    items: {
                        type: ['string', 'number', 'boolean', 'null']
                    }
                }
            },
            required: ['query']
        }
    };
}
export async function handleExecuteQuery(args, configHandler) {
    if (!args.query || typeof args.query !== 'string') {
        throw new ManagedError(ErrorCodes.INVALID_PARAMS, 'query is required and must be a string');
    }
    if (args.params && !Array.isArray(args.params)) {
        throw new ManagedError(ErrorCodes.INVALID_PARAMS, 'params must be an array');
    }
    // Validate parameters are basic types
    if (args.params) {
        for (const param of args.params) {
            const type = typeof param;
            if (param !== null && type !== 'string' && type !== 'number' && type !== 'boolean') {
                throw new ManagedError(ErrorCodes.INVALID_PARAMS, 'Query parameters must be string, number, boolean, or null');
            }
        }
    }
    // Check if connection is configured
    if (!configHandler.isConfigured()) {
        throw new ManagedError(ErrorCodes.NO_CONNECTION, 'Database connection not configured. Use configure_connection tool first');
    }
    const config = configHandler.getConfig();
    const queryExecutor = new QueryExecutor();
    // Create database client
    const client = new Client({
        host: config.host,
        port: config.port,
        database: config.database,
        user: config.user,
        password: config.password,
        ssl: config.ssl ? { rejectUnauthorized: false } : false,
        connectionTimeoutMillis: config.connectionTimeout,
        query_timeout: config.queryTimeout
    });
    try {
        await client.connect();
        const result = await queryExecutor.executeQuery(client, args.query, args.params);
        return {
            content: [{
                    type: 'text',
                    text: `📊 Query Results\n\n${JSON.stringify(result, null, 2)}`
                }]
        };
    }
    finally {
        await client.end();
    }
}