Remove X-Retry-After support.

This is part of simplifying URLRequestThrottler* now that it is
specific to extensions.  It also appears that nobody is using this
header.

BUG=119760


Review URL: http://codereview.chromium.org/10190002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@133558 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 3 insertions, 106 deletions

diff --git a/net/base/net_log_event_type_list.h b/net/base/net_log_event_type_list.h
index aa8dfc7..757fb4c 100644
--- a/net/base/net_log_event_type_list.h
+++ b/net/base/net_log_event_type_list.h
@@ -1286,13 +1286,6 @@ EVENT_TYPE(THROTTLING_DISABLED_FOR_HOST)
 //   }
 EVENT_TYPE(THROTTLING_REJECTED_REQUEST)
 
-// Emitted when throttling entry receives an X-Retry-After header.
-//   {
-//     "url":               <URL that was being requested>,
-//     "retry_after_ms":    <Milliseconds until retry-after expires>
-//   }
-EVENT_TYPE(THROTTLING_GOT_CUSTOM_RETRY_AFTER)
-
 // ------------------------------------------------------------------------
 // DnsTransaction
 // ------------------------------------------------------------------------
diff --git a/net/tools/testserver/backoff_server.py b/net/tools/testserver/backoff_server.py
index 3c6db1f..ca2c57cb 100755
--- a/net/tools/testserver/backoff_server.py
+++ b/net/tools/testserver/backoff_server.py
@@ -1,5 +1,5 @@
 #!/usr/bin/env python
-# Copyright (c) 2011 The Chromium Authors. All rights reserved.
+# Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
@@ -78,21 +78,14 @@ class RequestHandler(BaseHTTPServer.BaseHTTPRequestHandler):
 
     params = urlparse.parse_qs(urlparse.urlparse(self.path).query)
 
-    def SendCustomRetryIfRequested():
-      if params and 'custom-retry-after' in params:
-        custom_retry = params['custom-retry-after'][0]
-        self.send_header('X-Retry-After', custom_retry)
-
     if not params or not 'code' in params or params['code'][0] == '200':
       self.send_response(200)
       self.send_header('Content-Type', 'text/plain')
-      SendCustomRetryIfRequested()
       self.end_headers()
       self.wfile.write('OK')
     else:
       status_code = int(params['code'][0])
       self.send_response(status_code)
-      SendCustomRetryIfRequested()
       self.end_headers()
       self.wfile.write('Error %d' % int(status_code))
 
diff --git a/net/url_request/url_request_throttler_entry.cc b/net/url_request/url_request_throttler_entry.cc
index 3ef2db0..3154f9c 100644
--- a/net/url_request/url_request_throttler_entry.cc
+++ b/net/url_request/url_request_throttler_entry.cc
@@ -44,7 +44,6 @@ const double URLRequestThrottlerEntry::kDefaultMultiplyFactor = 1.4;
 const double URLRequestThrottlerEntry::kDefaultJitterFactor = 0.4;
 const int URLRequestThrottlerEntry::kDefaultMaximumBackoffMs = 15 * 60 * 1000;
 const int URLRequestThrottlerEntry::kDefaultEntryLifetimeMs = 2 * 60 * 1000;
-const char URLRequestThrottlerEntry::kRetryHeaderName[] = "X-Retry-After";
 const char URLRequestThrottlerEntry::kExponentialThrottlingHeader[] =
     "X-Chrome-Exponential-Throttling";
 const char URLRequestThrottlerEntry::kExponentialThrottlingDisableValue[] =
@@ -75,27 +74,6 @@ class RejectedRequestParameters : public NetLog::EventParameters {
   int release_after_ms_;
 };
 
-// NetLog parameters when a response contains an X-Retry-After header.
-class RetryAfterParameters : public NetLog::EventParameters {
- public:
-  RetryAfterParameters(const std::string& url_id,
-                       int retry_after_ms)
-      : url_id_(url_id),
-        retry_after_ms_(retry_after_ms) {
-  }
-
-  virtual Value* ToValue() const {
-    DictionaryValue* dict = new DictionaryValue();
-    dict->SetString("url", url_id_);
-    dict->SetInteger("retry_after_ms", retry_after_ms_);
-    return dict;
-  }
-
- private:
-  std::string url_id_;
-  int retry_after_ms_;
-};
-
 URLRequestThrottlerEntry::URLRequestThrottlerEntry(
     URLRequestThrottlerManager* manager,
     const std::string& url_id)
@@ -264,10 +242,6 @@ void URLRequestThrottlerEntry::UpdateWithResponse(
   } else {
     GetBackoffEntry()->InformOfRequest(true);
 
-    std::string retry_header = response->GetNormalizedValue(kRetryHeaderName);
-    if (!retry_header.empty())
-      HandleCustomRetryAfter(retry_header);
-
     std::string throttling_header = response->GetNormalizedValue(
         kExponentialThrottlingHeader);
     if (!throttling_header.empty())
@@ -337,36 +311,6 @@ base::TimeTicks URLRequestThrottlerEntry::ImplGetTimeNow() const {
   return base::TimeTicks::Now();
 }
 
-void URLRequestThrottlerEntry::HandleCustomRetryAfter(
-    const std::string& header_value) {
-  // Input parameter is the number of seconds to wait in a floating point value.
-  double time_in_sec = 0;
-  bool conversion_is_ok = base::StringToDouble(header_value, &time_in_sec);
-
-  // Conversion of custom retry-after header value failed.
-  if (!conversion_is_ok)
-    return;
-
-  // We must use an int value later so we transform this in milliseconds.
-  int64 value_ms = static_cast<int64>(0.5 + time_in_sec * 1000);
-
-  // We do not check for an upper bound; the server can set any Retry-After it
-  // desires. Recovery from error would involve restarting the browser.
-  if (value_ms < 0)
-    return;
-
-  net_log_.AddEvent(
-      NetLog::TYPE_THROTTLING_GOT_CUSTOM_RETRY_AFTER,
-      make_scoped_refptr(new RetryAfterParameters(url_id_, value_ms)));
-
-  base::TimeDelta value = base::TimeDelta::FromMilliseconds(value_ms);
-  GetBackoffEntry()->SetCustomReleaseTime(ImplGetTimeNow() + value);
-
-  UMA_HISTOGRAM_CUSTOM_TIMES(
-      "Throttling.CustomRetryAfterMs", value,
-      base::TimeDelta::FromSeconds(1), base::TimeDelta::FromHours(12), 50);
-}
-
 void URLRequestThrottlerEntry::HandleThrottlingHeader(
     const std::string& header_value,
     const std::string& host) {
diff --git a/net/url_request/url_request_throttler_entry.h b/net/url_request/url_request_throttler_entry.h
index 8a2589b..5c73c85 100644
--- a/net/url_request/url_request_throttler_entry.h
+++ b/net/url_request/url_request_throttler_entry.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -58,10 +58,6 @@ class NET_EXPORT URLRequestThrottlerEntry
   // Time after which the entry is considered outdated.
   static const int kDefaultEntryLifetimeMs;
 
-  // Name of the header that servers can use to ask clients to delay their
-  // next request.
-  static const char kRetryHeaderName[];
-
   // Name of the header that sites can use to opt out of exponential back-off
   // throttling.
   static const char kExponentialThrottlingHeader[];
@@ -118,9 +114,6 @@ class NET_EXPORT URLRequestThrottlerEntry
   // Equivalent to TimeTicks::Now(), virtual to be mockable for testing purpose.
   virtual base::TimeTicks ImplGetTimeNow() const;
 
-  // Used internally to increase release time following a retry-after header.
-  void HandleCustomRetryAfter(const std::string& header_value);
-
   // Used internally to handle the opt-out header.
   void HandleThrottlingHeader(const std::string& header_value,
                               const std::string& host);
diff --git a/net/url_request/url_request_throttler_test_support.cc b/net/url_request/url_request_throttler_test_support.cc
index 1c418c2..b6088ec 100644
--- a/net/url_request/url_request_throttler_test_support.cc
+++ b/net/url_request/url_request_throttler_test_support.cc
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -42,11 +42,6 @@ MockURLRequestThrottlerHeaderAdapter::~MockURLRequestThrottlerHeaderAdapter() {
 
 std::string MockURLRequestThrottlerHeaderAdapter::GetNormalizedValue(
     const std::string& key) const {
-  if (key == URLRequestThrottlerEntry::kRetryHeaderName &&
-      !fake_retry_value_.empty()) {
-    return fake_retry_value_;
-  }
-
   if (key ==
       URLRequestThrottlerEntry::kExponentialThrottlingHeader &&
       !fake_opt_out_value_.empty()) {
diff --git a/net/url_request/url_request_throttler_unittest.cc b/net/url_request/url_request_throttler_unittest.cc
index 8ea46b0..88243db 100644
--- a/net/url_request/url_request_throttler_unittest.cc
+++ b/net/url_request/url_request_throttler_unittest.cc
@@ -180,7 +180,6 @@ class URLRequestThrottlerEntryTest : public testing::Test {
 
 // List of all histograms we care about in these unit tests.
 const char* kHistogramNames[] = {
-  "Throttling.CustomRetryAfterMs",
   "Throttling.FailureCountAtSuccess",
   "Throttling.PerceivedDowntime",
   "Throttling.RequestThrottled",
@@ -255,26 +254,6 @@ TEST_F(URLRequestThrottlerEntryTest, InterfaceNotDuringExponentialBackoff) {
   ASSERT_EQ(0, samples_["Throttling.RequestThrottled"].counts(1));
 }
 
-TEST_F(URLRequestThrottlerEntryTest, InterfaceUpdateRetryAfter) {
-  // If the response we received has a retry-after field,
-  // the request should be delayed.
-  MockURLRequestThrottlerHeaderAdapter header_w_delay_header("5.5", "", 200);
-  entry_->UpdateWithResponse("", &header_w_delay_header);
-  EXPECT_GT(entry_->GetExponentialBackoffReleaseTime(), entry_->fake_time_now_)
-      << "When the server put a positive value in retry-after we should "
-         "increase release_time";
-
-  entry_->ResetToBlank(now_);
-  MockURLRequestThrottlerHeaderAdapter header_w_negative_header(
-      "-5.5", "", 200);
-  entry_->UpdateWithResponse("", &header_w_negative_header);
-  EXPECT_EQ(entry_->GetExponentialBackoffReleaseTime(), entry_->fake_time_now_)
-      << "When given a negative value, it should not change the release_time";
-
-  CalculateHistogramDeltas();
-  ASSERT_EQ(1, samples_["Throttling.CustomRetryAfterMs"].TotalCount());
-}
-
 TEST_F(URLRequestThrottlerEntryTest, InterfaceUpdateFailure) {
   MockURLRequestThrottlerHeaderAdapter failure_response(503);
   entry_->UpdateWithResponse("", &failure_response);