Append querystring to redirects

packages/proxy/src/handler.ts

@@ -1,21 +1,23 @@
 import { STATUS_CODES } from 'http';
+
 import {
  CloudFrontHeaders,
  CloudFrontResultResponse,
  CloudFrontRequestEvent,
  CloudFrontRequest,
 } from 'aws-lambda';
 
+import { appendQuerystring } from './util/append-querystring';
 import { fetchProxyConfig } from './util/fetch-proxy-config';
 import { generateCloudFrontHeaders } from './util/generate-cloudfront-headers';
-import { ProxyConfig, RouteResult } from './types';
-import { Proxy } from './proxy';
 import {
  createCustomOriginFromApiGateway,
  createCustomOriginFromUrl,
  serveRequestFromCustomOrigin,
  serveRequestFromS3Origin,
 } from './util/custom-origin';
+import { Proxy } from './proxy';
+import { ProxyConfig, RouteResult } from './types';
 
 let proxyConfig: ProxyConfig;
 let proxy: Proxy;
@@ -31,23 +33,38 @@ function isRedirect(
  routeResult.status >= 300 &&
  routeResult.status <= 309
  ) {
- if ('Location' in routeResult.headers) {
- let headers: CloudFrontHeaders = {};
-
- // If the redirect is permanent, cache the result
- if (routeResult.status === 301 || routeResult.status === 308) {
- headers['cache-control'] = [
+ const redirectTarget = routeResult.headers['Location'];
+ if (redirectTarget) {
+ // Append the original querystring to the redirect
+ const redirectTargetWithQuerystring = routeResult.uri_args
+ ? appendQuerystring(redirectTarget, routeResult.uri_args)
+ : redirectTarget;
+
+ // Override the Location header value with the appended querystring
+ routeResult.headers['Location'] = redirectTargetWithQuerystring;
+
+ // Redirects are not cached, see discussion for details:
+ // https://github.com/milliHQ/terraform-aws-next-js/issues/296
+ const initialHeaders: CloudFrontHeaders = {
+ 'cache-control': [
  {
  key: 'Cache-Control',
- value: 'public,max-age=31536000,immutable',
+ value: 'public, max-age=0, must-revalidate',
+ },
+ ],
+ 'content-type': [
+ {
+ key: 'Content-Type',
+ value: 'text/plain',
  },
- ];
- }
+ ],
+ };
 
  return {
  status: routeResult.status.toString(),
  statusDescription: STATUS_CODES[routeResult.status],
- headers: generateCloudFrontHeaders(headers, routeResult.headers),
+ headers: generateCloudFrontHeaders(initialHeaders, routeResult.headers),
+ body: `Redirecting to ${redirectTargetWithQuerystring} (${routeResult.status})`,
  };
  }
  }
@@ -77,7 +94,6 @@ async function main(
  ][0].value;
  const apiEndpoint = request.origin!.s3!.customHeaders['x-env-api-endpoint'][0]
  .value;
- let headers: Record<string, string> = {};
 
  try {
  if (!proxyConfig) {
@@ -107,9 +123,10 @@ async function main(
 
  // Append query string if we have one
  // @see: https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/lambda-event-structure.html
- const requestPath = `${request.uri}${
- request.querystring !== '' ? `?${request.querystring}` : ''
- }`;
+ const requestPath =
+ request.querystring !== ''
+ ? `${request.uri}?${request.querystring}`
+ : request.uri;
  const proxyResult = proxy.route(requestPath);
 
  // Check for redirect

packages/proxy/src/util/append-querystring.ts

@@ -0,0 +1,31 @@
+import { URL, URLSearchParams } from 'url';
+
+import isURL from './is-url';
+
+/**
+ * Append a querystring to a relative or absolute URL.
+ * Already existing searchParams are not overridden by the new searchParams.
+ *
+ * @param url The relative or absolute URL
+ * @param searchParams The searchParams that should be merged with the input URL
+ */
+function appendQuerystring(url: string, searchParams: URLSearchParams): string {
+ const urlObj = new URL(url, 'https://n');
+ const combinedSearchParams = new URLSearchParams({
+ ...Object.fromEntries(searchParams),
+ ...Object.fromEntries(urlObj.searchParams),
+ }).toString();
+
+ if (combinedSearchParams == '') {
+ return url;
+ }
+
+ if (isURL(url)) {
+ urlObj.search = '';
+ return `${urlObj.toString()}?${combinedSearchParams}`;
+ }
+
+ return `${urlObj.pathname}?${combinedSearchParams}`;
+}
+
+export { appendQuerystring };