managarten/packages/manadeck-database/src/client.ts

import { drizzle } from 'drizzle-orm/postgres-js';
import postgres from 'postgres';
import * as schema from './schema';

// Singleton instance for the database client
let dbInstance: ReturnType<typeof drizzle<typeof schema>> | null = null;
let pgClient: ReturnType<typeof postgres> | null = null;

/**
 * Get the database URL from environment variables
 */
function getDatabaseUrl(): string {
  const url = process.env.DATABASE_URL || process.env.MANADECK_DATABASE_URL;
  if (!url) {
    throw new Error(
      'Database URL not found. Set DATABASE_URL or MANADECK_DATABASE_URL environment variable.'
    );
  }
  return url;
}

/**
 * Create a new database client
 * Uses connection pooling with sensible defaults for serverless environments
 */
export function createClient(connectionString?: string) {
  const url = connectionString || getDatabaseUrl();

  const client = postgres(url, {
    max: 10, // Maximum connections in the pool
    idle_timeout: 20, // Close idle connections after 20 seconds
    connect_timeout: 10, // Connection timeout in seconds
    prepare: false, // Disable prepared statements for serverless
  });

  return drizzle(client, { schema });
}

/**
 * Get the singleton database instance
 * Creates a new instance if one doesn't exist
 */
export function getDb() {
  if (!dbInstance) {
    const url = getDatabaseUrl();
    pgClient = postgres(url, {
      max: 10,
      idle_timeout: 20,
      connect_timeout: 10,
      prepare: false,
    });
    dbInstance = drizzle(pgClient, { schema });
  }
  return dbInstance;
}

/**
 * Close the database connection
 * Should be called when shutting down the application
 */
export async function closeDb() {
  if (pgClient) {
    await pgClient.end();
    pgClient = null;
    dbInstance = null;
  }
}

// Export the database type for typing purposes
export type Database = ReturnType<typeof createClient>;

// Re-export commonly used Drizzle utilities
export { eq, ne, gt, gte, lt, lte, and, or, not, inArray, notInArray, isNull, isNotNull, like, ilike, sql, asc, desc, count, sum, avg, min, max } from 'drizzle-orm';