Intlayer

import { type NextFetchEvent, type NextRequest, NextResponse, } from 'next/server'; /** * Utility to combine multiple Next.js proxies into one. * * It executes proxies in order, merges headers, and correctly handles * redirects and rewrites. * * @example * import { multipleProxies, intlayerProxy } from "next-intlayer/proxy"; * import { NextResponse } from "next/server"; * * const authMiddleware = (req: NextRequest) => { * if (!req.cookies.get("token")) { * return NextResponse.redirect(new URL("/login", req.url)); * } * return NextResponse.next(); * }; * * export default multipleProxies([ * intlayerProxy, * authMiddleware, * ]); * * @param proxies - An array of proxy functions to execute in order. * @returns A single proxy function that runs all provided proxies. */ export const multipleProxies = ( proxies: (( req: NextRequest, event?: NextFetchEvent, response?: NextResponse ) => NextResponse | Promise<NextResponse>)[] ) => async (req: NextRequest, event?: NextFetchEvent, response?: NextResponse) => { // Array to store proxy headers const proxyHeader: Headers[] = []; // Loop through proxy functions for (const proxy of proxies) { // Execute proxy function and await the result const result = await proxy(req, event, response); // Check if the result is not okay and return it if (!result.ok) { return result; } // Push proxy headers to the array proxyHeader.push(result.headers); } // Merge all the headers to check if there is a redirection or rewrite const mergedHeaders = new Headers(); // Merge all the custom headers added by the proxies const transmittedHeaders = new Headers(); // Merge headers proxyHeader.forEach((header) => { for (const [key, value] of header.entries()) { mergedHeaders.append(key, value); // check if it's a custom header added by one of the proxies if (key.startsWith('x-middleware-request-')) { // remove the prefix to get the original key const fixedKey = key.replace('x-middleware-request-', ''); // add the original key to the transmitted headers transmittedHeaders.append(fixedKey, value); } } }); // Look for the 'x-middleware-request-redirect' header const redirect = mergedHeaders.get('x-middleware-request-redirect'); // If a redirection is required based on the proxy headers if (redirect) { // Perform the redirection return NextResponse.redirect(new URL(redirect, req.url), { status: 307, // Temporary redirect }); } // Look for the 'x-middleware-rewrite' header const rewrite = mergedHeaders.get('x-middleware-rewrite'); if (rewrite) { // Perform the rewrite return NextResponse.rewrite(new URL(rewrite, req.url), { request: { headers: transmittedHeaders, }, }); } // Default: continue to next proxy return NextResponse.next({ request: { headers: transmittedHeaders, }, }); };