From 896f36d30c6fe8bea89f470b5d85967b682ae28d Mon Sep 17 00:00:00 2001
From: Kershaw Chang <kershaw@mozilla.com>
Date: Thu, 18 Jul 2019 12:19:10 +0000
Subject: [PATCH] Bug 1555927 - Cache 204 response r=mayhemer

Differential Revision: https://phabricator.services.mozilla.com/D35710

--HG--
extra : moz-landing-system : lando
---
 netwerk/protocol/http/nsHttpResponseHead.cpp  |  1 +
 netwerk/test/unit/test_cache_204_response.js  | 62 +++++++++++++++++++
 netwerk/test/unit/xpcshell.ini                |  2 +-
 .../meta/fetch/http-cache/heuristic.html.ini  |  6 --
 .../meta/fetch/http-cache/status.html.ini     |  6 --
 5 files changed, 64 insertions(+), 13 deletions(-)
 create mode 100644 netwerk/test/unit/test_cache_204_response.js

diff --git a/netwerk/protocol/http/nsHttpResponseHead.cpp b/netwerk/protocol/http/nsHttpResponseHead.cpp
index acc1576aa43d..d74e43ccbfbb 100644
--- a/netwerk/protocol/http/nsHttpResponseHead.cpp
+++ b/netwerk/protocol/http/nsHttpResponseHead.cpp
@@ -711,6 +711,7 @@ bool nsHttpResponseHead::MustValidate() {
       // Success codes
     case 200:
     case 203:
+    case 204:
     case 206:
       // Cacheable redirects
     case 300:
diff --git a/netwerk/test/unit/test_cache_204_response.js b/netwerk/test/unit/test_cache_204_response.js
new file mode 100644
index 000000000000..c5855210762b
--- /dev/null
+++ b/netwerk/test/unit/test_cache_204_response.js
@@ -0,0 +1,62 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+Test if 204 response is cached.
+1. Make first http request and return a 204 response.
+2. Check if the first response is not cached.
+3. Make second http request and check if the response is cached.
+
+*/
+
+"use strict";
+
+const { HttpServer } = ChromeUtils.import("resource://testing-common/httpd.js");
+
+function test_handler(metadata, response) {
+  response.setHeader("Content-Type", "text/html", false);
+  response.setHeader("Cache-control", "max-age=9999", false);
+  response.setStatusLine(metadata.httpVersion, 204, "No Content");
+}
+
+function make_channel(url) {
+  let channel = NetUtil.newChannel({
+    uri: url,
+    loadUsingSystemPrincipal: true,
+  }).QueryInterface(Ci.nsIHttpChannel);
+  return channel;
+}
+
+async function get_response(channel, fromCache) {
+  return new Promise(resolve => {
+    channel.asyncOpen(
+      new ChannelListener((request, buffer, ctx, isFromCache) => {
+        ok(fromCache == isFromCache, `got response from cache = ${fromCache}`);
+        resolve();
+      })
+    );
+  });
+}
+
+async function stop_server(httpserver) {
+  return new Promise(resolve => {
+    httpserver.stop(resolve);
+  });
+}
+
+add_task(async function() {
+  let httpserver = new HttpServer();
+  httpserver.registerPathHandler("/testdir", test_handler);
+  httpserver.start(-1);
+  const PORT = httpserver.identity.primaryPort;
+  const URI = `http://localhost:${PORT}/testdir`;
+
+  let response;
+
+  await get_response(make_channel(URI, "GET"), false);
+  await get_response(make_channel(URI, "GET"), true);
+
+  await stop_server(httpserver);
+});
diff --git a/netwerk/test/unit/xpcshell.ini b/netwerk/test/unit/xpcshell.ini
index b488ba32db91..ddf00d130e30 100644
--- a/netwerk/test/unit/xpcshell.ini
+++ b/netwerk/test/unit/xpcshell.ini
@@ -457,4 +457,4 @@ run-sequentially = one http2 node proxy is used for all tests, this test is usin
 skip-if = true
 [test_head_request_no_response_body.js]
 [test_disabled_ftp.js]
-
+[test_cache_204_response.js]
diff --git a/testing/web-platform/meta/fetch/http-cache/heuristic.html.ini b/testing/web-platform/meta/fetch/http-cache/heuristic.html.ini
index 17b2b48eba25..6984591b0ee9 100644
--- a/testing/web-platform/meta/fetch/http-cache/heuristic.html.ini
+++ b/testing/web-platform/meta/fetch/http-cache/heuristic.html.ini
@@ -2,9 +2,6 @@
   [HTTP cache reuses an unknown response with Last-Modified based upon heuristic freshness when Cache-Control: public is present.]
     expected: FAIL
 
-  [HTTP cache reuses a 204 No Content response with Last-Modified based upon heuristic freshness.]
-    expected: FAIL
-
   [HTTP cache reuses a 404 Not Found response with Last-Modified based upon heuristic freshness.]
     expected: FAIL
 
@@ -20,9 +17,6 @@
   [HTTP cache reuses an unknown response with Last-Modified based upon heuristic freshness when Cache-Control: public is present]
     expected: FAIL
 
-  [HTTP cache reuses a 204 No Content response with Last-Modified based upon heuristic freshness]
-    expected: FAIL
-
   [HTTP cache reuses a 404 Not Found response with Last-Modified based upon heuristic freshness]
     expected: FAIL
 
diff --git a/testing/web-platform/meta/fetch/http-cache/status.html.ini b/testing/web-platform/meta/fetch/http-cache/status.html.ini
index 50255f73056e..44ba6a37c58c 100644
--- a/testing/web-platform/meta/fetch/http-cache/status.html.ini
+++ b/testing/web-platform/meta/fetch/http-cache/status.html.ini
@@ -1,7 +1,4 @@
 [status.html]
-  [HTTP cache avoids going to the network if it has a fresh 204 response.]
-    expected: FAIL
-
   [HTTP cache avoids going to the network if it has a fresh 299 response.]
     expected: FAIL
 
@@ -29,9 +26,6 @@
   [HTTP cache avoids going to the network if it has a fresh 599 response.]
     expected: FAIL
 
-  [HTTP cache avoids going to the network if it has a fresh 204 response]
-    expected: FAIL
-
   [HTTP cache avoids going to the network if it has a fresh 299 response]
     expected: FAIL