Prisma / express-session simple integration

prisma-session.ts

// Offensively simple shim on top of https://www.npmjs.com/package/connect-pg-simple

import { PrismaClient } from '@prisma/client';
import connectPgSimple from 'connect-pg-simple';
import session from 'express-session';
import { format } from '@scaleleap/pg-format';

type Debugger = (arg: Record<string, unknown>) => Promise<void>;

export const consoleDebugger: Debugger = async (payload) => {
  console.dir(payload, { depth: null });
};

class ShimPool {
  #_debugId: number = 0;
  constructor(
    public prisma: PrismaClient,
    private debug: Debugger | undefined
  ) {}

  async query(query: string, params: unknown[]) {
    let debugId = 0;

    if (this.debug) {
      debugId = this.#_debugId++;
      this.debug({ _: 'original', query, params, debugId });
    }

    // pg to pg-format param markup
    const reParam = query.replaceAll(/\$(\d)/g, '%$1$$L');
    // Escape the query
    const safeQuery = format(reParam, ...params);
    if (this.debug) this.debug({ _: 'newQuery', safeQuery, debugId });

    // Run and return it
    const rows = await this.prisma.$queryRawUnsafe(safeQuery);
    if (this.debug) this.debug({ _: 'results', rows, debugId });
    return { rows };
  }
}

export function sessionStore(prismaClient: PrismaClient, tableName: string, debug?: Debugger): session.Store {
  const PgSession = connectPgSimple(session);
  const pool = new ShimPool(prismaClient, debug);
  return new PgSession({ pool: pool as any, tableName });
}