middleware.js

/*import createMiddleware from 'next-intl/middleware';
 
export default createMiddleware({
  locales: ['en', 'es'],
  defaultLocale: 'en'
});
 
export const config = {
  matcher: ['/((?!api|_next|.*\\..*).*)']
};*/


import { NextResponse } from 'next/server';
import { i18n } from './i18n-config';
import { match as matchLocale } from '@formatjs/intl-localematcher';
import Negotiator from 'negotiator';

function getLocale(request) {
  // Negotiator expects plain object so we need to transform headers
  const negotiatorHeaders = {};
  request.headers.forEach((value, key) => (negotiatorHeaders[key] = value));

  // Use negotiator and intl-localematcher to get best locale
  let languages = new Negotiator({ headers: negotiatorHeaders }).languages();
  // @ts-ignore locales are readonly
  const locales = i18n.locales;
  return matchLocale(languages, locales, i18n.defaultLocale)
}

export function middleware(request) {
  const pathname = request.nextUrl.pathname;

  // // `/_next/` and `/api/` are ignored by the watcher, but we need to ignore files in `public` manually.
  // // If you have one
  // if (
  //   [
  //     '/manifest.json',
  //     '/favicon.ico',
  //     // Your other files in `public`
  //   ].includes(pathname)
  // )
  //   return

  // Check if there is any supported locale in the pathname
  const pathnameIsMissingLocale = i18n.locales.every(
    (locale) => !pathname.startsWith(`/${locale}/`) && pathname !== `/${locale}`
  )

  // Redirect if there is no locale
  if (pathnameIsMissingLocale) {
    const locale = getLocale(request)

    // e.g. incoming request is /products
    // The new URL is now /en-US/products
    return NextResponse.redirect(new URL(`/${locale}/${pathname}`, request.url))
  }
}

export const config = {
  // Matcher ignoring `/_next/` and `/api/`
  matcher: ['/((?!api|_next/static|_next/image|favicon.ico).*)'],
}