chore: refactor for clarity

Author: orinokai

edge-runtime/lib/response.ts

@@ -20,7 +20,7 @@ export interface FetchEventResult {
 
 interface BuildResponseOptions {
   context: Context
-  config?: NetlifyNextRequest['nextConfig']
+  nextConfig?: NetlifyNextRequest['nextConfig']
   locale?: string
   request: Request
   result: FetchEventResult
@@ -29,7 +29,7 @@ interface BuildResponseOptions {
 
 export const buildResponse = async ({
   context,
-  config,
+  nextConfig,
   locale,
   request,
   result,
@@ -185,9 +185,9 @@ export const buildResponse = async ({
     }
 
     // respect trailing slash rules to prevent 308s
-    rewriteUrl.pathname = normalizeTrailingSlash(rewriteUrl.pathname, config?.trailingSlash)
+    rewriteUrl.pathname = normalizeTrailingSlash(rewriteUrl.pathname, nextConfig?.trailingSlash)
 
-    const target = normalizeLocalizedTarget({ target: rewriteUrl.toString(), request, config })
+    const target = normalizeLocalizedTarget({ target: rewriteUrl.toString(), request, nextConfig })
     if (target === request.url) {
       logger.withFields({ rewrite_url: rewrite }).debug('Rewrite url is same as original url')
       return
@@ -199,7 +199,7 @@ export const buildResponse = async ({
 
   // If we are redirecting a request that had a locale in the URL, we need to add it back in
   if (redirect && locale) {
-    redirect = normalizeLocalizedTarget({ target: redirect, request, config })
+    redirect = normalizeLocalizedTarget({ target: redirect, request, nextConfig })
     if (redirect === request.url) {
       logger.withFields({ rewrite_url: rewrite }).debug('Rewrite url is same as original url')
       return
@@ -233,16 +233,16 @@ export const buildResponse = async ({
 function normalizeLocalizedTarget({
   target,
   request,
-  config,
+  nextConfig,
   locale,
 }: {
   target: string
   request: Request
-  config?: NetlifyNextRequest['nextConfig']
+  nextConfig?: NetlifyNextRequest['nextConfig']
   locale?: string
 }) {
   const targetUrl = new URL(target, request.url)
-  const normalizedTarget = normalizeLocalePath(targetUrl.pathname, config?.i18n?.locales)
+  const normalizedTarget = normalizeLocalePath(targetUrl.pathname, nextConfig?.i18n?.locales)
   const targetPathname = normalizedTarget.pathname
   const targetLocale = normalizedTarget.detectedLocale ?? locale
 
@@ -251,9 +251,10 @@ function normalizeLocalizedTarget({
     !targetPathname.startsWith(`/api/`) &&
     !targetPathname.startsWith(`/_next/static/`)
   ) {
-    targetUrl.pathname = addBasePath(`/${targetLocale}${targetPathname}`, config?.basePath) || `/`
+    targetUrl.pathname =
+      addBasePath(`/${targetLocale}${targetPathname}`, nextConfig?.basePath) || `/`
   } else {
-    targetUrl.pathname = addBasePath(targetPathname, config?.basePath) || `/`
+    targetUrl.pathname = addBasePath(targetPathname, nextConfig?.basePath) || `/`
   }
   return targetUrl.toString()
 }

edge-runtime/middleware.ts

@@ -32,16 +32,19 @@ export async function handleMiddleware(
   nextHandler: NextHandler,
 ) {
   const url = new URL(request.url)
+  const query = searchParamsToUrlQuery(url.searchParams)
+  const { localizedUrl, locale } = localizeRequest(url, nextConfig)
   const reqLogger = logger
     .withLogLevel(
       request.headers.has(InternalHeaders.NFDebugLogging) ? LogLevel.Debug : LogLevel.Log,
     )
     .withFields({ url_path: url.pathname })
     .withRequestID(request.headers.get(InternalHeaders.NFRequestID))
 
+  // Convert the incoming request to a Next.js request, which includes
+  // normalizing the URL, adding geo and IP information and converting
+  // the headers to a plain object, among other things.
   const nextRequest = buildNextRequest(request, context, nextConfig)
-  const { localizedUrl, locale } = localizeRequest(url, nextConfig)
-  const query = searchParamsToUrlQuery(url.searchParams)
 
   // While we have already checked the path when mapping to the edge function,
   // Next.js supports extra rules that we need to check here too, because we
@@ -56,7 +59,7 @@ export async function handleMiddleware(
     const result = await nextHandler({ request: nextRequest })
     const response = await buildResponse({
       context,
-      config: nextRequest.nextConfig,
+      nextConfig: nextRequest.nextConfig,
       locale,
       request,
       result,