Postgraphile as a Next.js API

pages_SLASH_[apimethod].tsx

import { NextApiRequest, NextApiResponse } from 'next'
import { middleware } from '../../src/graphile/postgraphileMiddleware.js'

export default async function(req: NextApiRequest, res: NextApiResponse) {
  return new Promise((resolve, reject) => {
    middleware(req, res)
    res.once('finish', () => resolve(true))
    res.once('error', e => reject(e))
  })
}

export const config = {
  api: {
    bodyParser: false,
  },
}

src_SLASH_graphile_SLASH_postgraphileMiddleware.js

import PgSimplifyInflectorPlugin from '@graphile-contrib/pg-simplify-inflector'
import { postgraphile } from 'postgraphile'

const sqlClient = new pg.Pool({
  connectionString: DATABASE_URL,
  // other settings
})

export const middleware = postgraphile(sqlClient, 'public', {
  graphiql: process.env.NODE_ENV !== 'production',
  appendPlugins: [
    PgSimplifyInflectorPlugin,
    // ... your plugins
  ],
  graphqlRoute: '/api/graphql',
  graphiqlRoute: '/api/graphiql',
  showErrorStack: true,
})