supabase/studio/pages/api/projects/[ref]/usage.ts

import { NextApiRequest, NextApiResponse } from 'next'
import apiWrapper from 'lib/api/apiWrapper'

export default (req: NextApiRequest, res: NextApiResponse) => apiWrapper(req, res, handler)

async function handler(req: NextApiRequest, res: NextApiResponse) {
  const { method } = req

  switch (method) {
    case 'GET':
      return handleGetAll(req, res)
    default:
      res.setHeader('Allow', ['GET'])
      res.status(405).json({ data: null, error: { message: `Method ${method} Not Allowed` } })
  }
}

const handleGetAll = async (req: NextApiRequest, res: NextApiResponse) => {
  return res
    .status(200)
    .json({ dbSize: '888888', authUsers: '0', bucketSize: '888888', dbTables: '0' })
}