jarv.is/lib/helpers/prisma.ts

import { PrismaClient } from "@prisma/client";
import { PrismaLibSQL } from "@prisma/adapter-libsql";
import { createClient } from "@libsql/client";

// 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 libsql = createClient({
    // TODO: use a local .db file for development. https://www.prisma.io/docs/orm/overview/databases/sqlite#connection-url
    url: `${process.env.TURSO_DATABASE_URL}`,
    authToken: `${process.env.TURSO_AUTH_TOKEN}`,
  });

  const adapter = new PrismaLibSQL(libsql);

  return new PrismaClient({ adapter });
};

declare global {
  // eslint-disable-next-line no-var
  var prisma: undefined | ReturnType<typeof prismaClientSingleton>;
}

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

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