Interactive database console for Prisma ORM (Typescript)

db-console.ts

#!/usr/bin/env tsx

// Backend Console - Interactive Prisma REPL
// Similar to Rails console for experimenting with database queries

import { PrismaClient } from '@prisma/client';
import repl from 'repl';
import util from 'util';

// Initialize Prisma Client with event-based logging to see SQL queries and bound parameters
const prisma = new PrismaClient({
  log: [
    { emit: 'event', level: 'query' },
    { emit: 'stdout', level: 'error' },
    { emit: 'stdout', level: 'info' },
    { emit: 'stdout', level: 'warn' },
  ],
});

// Subscribe to query events to log SQL and bound parameters
prisma.$on('query', (e) => {
  console.log('---');
  console.log(e.query);
  console.log(e.params);
  console.log(String(e.duration) + 'ms');
  console.log('---');
});

function usage() {
  console.log('🚀 Backend Console');
  console.log('📊 Prisma Client loaded as "prisma"');
  console.log('💡 Examples:');
  console.log('   await prisma.user.findMany()');
  console.log('   await prisma.tenant.count()');
  console.log('   await prisma.$queryRaw`SELECT COUNT(*) FROM "user"`');
  console.log(
    '   await prisma.organization.findFirst({ include: { tenants: true } })',
  );
  console.log('');
}
usage();

// Start REPL with Prisma client in context
const replServer = repl.start({
  prompt: 'prisma-console> ',
  useColors: true,
});

// Add prisma to the REPL context
replServer.context.prisma = prisma;

// Add helpful utilities to the REPL context
replServer.context.inspect = util.inspect;
replServer.context.log = console.log;
replServer.context.help = usage;

// Add types to the REPL context for better autocompletion
replServer.context.PrismaClient = PrismaClient;

// Cleanup function for disconnecting Prisma
function cleanupAndExit() {
  console.log('\n👋 Disconnecting from database...');
  prisma
    .$disconnect()
    .catch((err: unknown) => {
      console.error('Error disconnecting from database:', err);
    })
    .finally(() => process.exit(0));
}

// Handle cleanup on exit
replServer.on('exit', cleanupAndExit);
process.on('SIGINT', cleanupAndExit);