jarv.is/lib/helpers/prisma.ts

import { PrismaClient } from "@prisma/client";
import { PrismaNeon } from "@prisma/adapter-neon";
import { Pool, neonConfig } from "@neondatabase/serverless";
import ws from "ws";

// https://www.prisma.io/blog/serverless-database-drivers-KML1ehXORxZV#use-neon-with-neondatabaseserverless
neonConfig.webSocketConstructor = ws;

// creating PrismaClient here prevents next.js from starting too many concurrent prisma instances and exhausting the
// number of connection pools available (especially when hot reloading from `next dev`).
// https://www.prisma.io/docs/guides/other/troubleshooting-orm/help-articles/nextjs-prisma-client-dev-practices

const prismaClientSingleton = () => {
  const pool = new Pool({
    connectionString: process.env.DATABASE_URL,
    ssl: true,
  });
  const adapter = new PrismaNeon(pool);
  return new PrismaClient({ adapter });
};

type PrismaClientSingleton = ReturnType<typeof prismaClientSingleton>;

const globalForPrisma = globalThis as unknown as {
  prisma: PrismaClientSingleton | undefined;
};

export const prisma = globalForPrisma.prisma ?? prismaClientSingleton();

if (process.env.NODE_ENV !== "production") globalForPrisma.prisma = prisma;