Bypass the host cache when you refresh a page.

BUG=13163
TEST=HttpNetworkTransactionTest.BypassHostCacheOnRefresh, HostResolverTest.BypassCache

Review URL: http://codereview.chromium.org/125154

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@18474 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 53 insertions, 6 deletions

diff --git a/net/http/http_network_transaction.cc b/net/http/http_network_transaction.cc
index f4a7879..2383c38 100644
--- a/net/http/http_network_transaction.cc
+++ b/net/http/http_network_transaction.cc
@@ -577,16 +577,11 @@ int HttpNetworkTransaction::DoInitConnection() {
   // that we resolve to.
   resolve_info.set_referrer(request_->referrer);
 
-// TODO(eroman): Enable this!
-// Needs some unit-tests before turning on.
-// http://crbug.com/13163
-#if 0
   // If the user is refreshing the page, bypass the host cache.
   if (request_->load_flags & LOAD_BYPASS_CACHE ||
       request_->load_flags & LOAD_DISABLE_CACHE) {
-    resolve_info.allow_cached_response = false;
+    resolve_info.set_allow_cached_response(false);
   }
-#endif
 
   int rv = connection_.Init(connection_group, resolve_info, request_->priority,
                             &io_callback_);
diff --git a/net/http/http_network_transaction_unittest.cc b/net/http/http_network_transaction_unittest.cc
index 59bfffc..778bd8f 100644
--- a/net/http/http_network_transaction_unittest.cc
+++ b/net/http/http_network_transaction_unittest.cc
@@ -3104,4 +3104,56 @@ TEST_F(HttpNetworkTransactionTest, ResolveMadeWithReferrer) {
   EXPECT_TRUE(resolution_observer.did_complete_with_expected_referrer());
 }
 
+// Make sure that when the load flags contain LOAD_BYPASS_CACHE, the resolver's
+// host cache is bypassed.
+TEST_F(HttpNetworkTransactionTest, BypassHostCacheOnRefresh) {
+  SessionDependencies session_deps;
+  scoped_ptr<HttpTransaction> trans(new HttpNetworkTransaction(
+      CreateSession(&session_deps), &session_deps.socket_factory));
+
+  // Warm up the host cache so it has an entry for "www.google.com" (by doing
+  // a synchronous lookup.)
+  AddressList addrlist;
+  int rv = session_deps.host_resolver.Resolve(
+    HostResolver::RequestInfo("www.google.com", 80), &addrlist, NULL, NULL);
+  EXPECT_EQ(OK, rv);
+
+  // Verify that it was added to host cache, by doing a subsequent async lookup
+  // and confirming it completes synchronously.
+  TestCompletionCallback resolve_callback;
+  rv = session_deps.host_resolver.Resolve(
+      HostResolver::RequestInfo("www.google.com", 80), &addrlist,
+      &resolve_callback, NULL);
+  EXPECT_EQ(OK, rv);
+
+  // Inject a failure the next time that "www.google.com" is resolved. This way
+  // we can tell if the next lookup hit the cache, or the "network".
+  // (cache --> success, "network" --> failure).
+  scoped_refptr<RuleBasedHostMapper> host_mapper(new RuleBasedHostMapper());
+  ScopedHostMapper scoped_host_mapper(host_mapper.get());
+  host_mapper->AddSimulatedFailure("www.google.com");
+
+  // Connect up a mock socket which will fail with ERR_UNEXPECTED during the
+  // first read -- this won't be reached as the host resolution will fail first.
+  MockRead data_reads[] = { MockRead(false, ERR_UNEXPECTED) };
+  StaticMockSocket data(data_reads, NULL);
+  session_deps.socket_factory.AddMockSocket(&data);
+
+  // Issue a request, asking to bypass the cache(s).
+  HttpRequestInfo request;
+  request.method = "GET";
+  request.load_flags = LOAD_BYPASS_CACHE;
+  request.url = GURL("http://www.google.com/");
+
+  // Run the request.
+  TestCompletionCallback callback;
+  rv = trans->Start(&request, &callback);
+  ASSERT_EQ(ERR_IO_PENDING, rv);
+  rv = callback.WaitForResult();
+
+  // If we bypassed the cache, we would have gotten a failure while resolving
+  // "www.google.com".
+  EXPECT_EQ(ERR_NAME_NOT_RESOLVED, rv);
+}
+
 }  // namespace net