1 // Copyright (c) 2011 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef NET_URL_REQUEST_URL_REQUEST_THROTTLER_ENTRY_INTERFACE_H_ 6 #define NET_URL_REQUEST_URL_REQUEST_THROTTLER_ENTRY_INTERFACE_H_ 7 #pragma once 8 9 #include "base/basictypes.h" 10 #include "base/memory/ref_counted.h" 11 #include "base/time.h" 12 13 namespace net { 14 15 class URLRequestThrottlerHeaderInterface; 16 17 // Interface provided on entries of the URL request throttler manager. 18 class URLRequestThrottlerEntryInterface 19 : public base::RefCountedThreadSafe<URLRequestThrottlerEntryInterface> { 20 public: URLRequestThrottlerEntryInterface()21 URLRequestThrottlerEntryInterface() {} 22 23 // Returns true when we have encountered server errors and are doing 24 // exponential back-off. 25 // URLRequestHttpJob checks this method prior to every request; it 26 // cancels requests if this method returns true. 27 virtual bool IsDuringExponentialBackoff() const = 0; 28 29 // Calculates a recommended sending time for the next request and reserves it. 30 // The sending time is not earlier than the current exponential back-off 31 // release time or |earliest_time|. Moreover, the previous results of 32 // the method are taken into account, in order to make sure they are spread 33 // properly over time. 34 // Returns the recommended delay before sending the next request, in 35 // milliseconds. The return value is always positive or 0. 36 // Although it is not mandatory, respecting the value returned by this method 37 // is helpful to avoid traffic overload. 38 virtual int64 ReserveSendingTimeForNextRequest( 39 const base::TimeTicks& earliest_time) = 0; 40 41 // Returns the time after which requests are allowed. 42 virtual base::TimeTicks GetExponentialBackoffReleaseTime() const = 0; 43 44 // This method needs to be called each time a response is received. 45 virtual void UpdateWithResponse( 46 const std::string& host, 47 const URLRequestThrottlerHeaderInterface* response) = 0; 48 49 // Lets higher-level modules, that know how to parse particular response 50 // bodies, notify of receiving malformed content for the given URL. This will 51 // be handled by the throttler as if an HTTP 5xx response had been received to 52 // the request, i.e. it will count as a failure. 53 virtual void ReceivedContentWasMalformed() = 0; 54 55 protected: 56 friend class base::RefCountedThreadSafe<URLRequestThrottlerEntryInterface>; ~URLRequestThrottlerEntryInterface()57 virtual ~URLRequestThrottlerEntryInterface() {} 58 59 private: 60 friend class base::RefCounted<URLRequestThrottlerEntryInterface>; 61 DISALLOW_COPY_AND_ASSIGN(URLRequestThrottlerEntryInterface); 62 }; 63 64 } // namespace net 65 66 #endif // NET_URL_REQUEST_URL_REQUEST_THROTTLER_ENTRY_INTERFACE_H_ 67