Function getNodeMiddleware

packages/next/src/utils.ts:3958–4142

({
  config,
  baseDir,
  projectDir,
  entryPath,
  nextVersion,
  nodeVersion,
  lstatSema,
  lstatResults,
  pageExtensions,
  routesManifest,
  outputDirectory,
  prerenderBypassToken,
  isCorrectMiddlewareOrder,
  functionsConfigManifest,
  requiredServerFilesManifest,
}: {
  config: Config;
  baseDir: string;
  projectDir: string;
  lstatSema: Sema;
  lstatResults: { [key: string]: ReturnType<typeof lstat> };
  entryPath: string;
  nodeVersion: string;
  pageExtensions: string[];
  nextVersion: string;
  outputDirectory: string;
  prerenderBypassToken: string;
  isCorrectMiddlewareOrder: boolean;
  routesManifest: RoutesManifest;
  functionsConfigManifest?: FunctionsConfigManifestV1;
  requiredServerFilesManifest: NextRequiredServerFilesManifest;
})

}

export async function getNodeMiddleware({
  config,
  baseDir,
  projectDir,
  entryPath,
  nextVersion,
  nodeVersion,
  lstatSema,
  lstatResults,
  pageExtensions,
  routesManifest,
  outputDirectory,
  prerenderBypassToken,
  isCorrectMiddlewareOrder,
  functionsConfigManifest,
  requiredServerFilesManifest,
}: {
  config: Config;
  baseDir: string;
  projectDir: string;
  lstatSema: Sema;
  lstatResults: { [key: string]: ReturnType<typeof lstat> };
  entryPath: string;
  nodeVersion: string;
  pageExtensions: string[];
  nextVersion: string;
  outputDirectory: string;
  prerenderBypassToken: string;
  isCorrectMiddlewareOrder: boolean;
  routesManifest: RoutesManifest;
  functionsConfigManifest?: FunctionsConfigManifestV1;
  requiredServerFilesManifest: NextRequiredServerFilesManifest;
}): Promise<null | {
  lambdas: Record<string, NodejsLambda>;
  routes: RouteWithSrc[];
}> {
  const middlewareFunctionConfig =
    functionsConfigManifest?.functions['/_middleware'];

  if (!middlewareFunctionConfig || !middlewareFunctionConfig.matchers) {
    return null;
  }
  const routes: RouteWithSrc[] = [];
  // Pass page: '/' to skip basePath addition in getRouteMatchers(), since
  // functions-config-manifest matchers already have basePath baked in by
  // Next.js build. This matches the behavior for edge middleware where
  // page is '/' (root middleware) and basePath is not added.
  const routeMatchers = getRouteMatchers(
    { matchers: middlewareFunctionConfig.matchers, page: '/' },
    routesManifest
  );

  for (const matcher of routeMatchers) {
    const route: Route = {
      continue: true,
      src: matcher.regexp,
      has: matcher.has,
      missing: [