13f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen// Copyright (c) 2011 The Chromium Authors. All rights reserved. 2c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// Use of this source code is governed by a BSD-style license that can be 3c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// found in the LICENSE file. 4c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 5c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// Support modularity by calling to load a new SDCH filter dictionary. 6c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// Note that this sort of calling can't be done in the /net directory, as it has 7c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch// no concept of the HTTP cache (which is only visible at the browser level). 8c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 9c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#ifndef CHROME_BROWSER_NET_SDCH_DICTIONARY_FETCHER_H_ 10c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#define CHROME_BROWSER_NET_SDCH_DICTIONARY_FETCHER_H_ 113345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick#pragma once 12c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 13c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include <queue> 14c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include <set> 15c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include <string> 16c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 17ddb351dbec246cf1fab5ec20d2d5520909041de1Kristian Monsen#include "base/memory/scoped_ptr.h" 18c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include "base/task.h" 19c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include "chrome/common/net/url_fetcher.h" 20c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#include "net/base/sdch_manager.h" 21c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 22c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdochclass SdchDictionaryFetcher : public URLFetcher::Delegate, 2372a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen public net::SdchFetcher { 24c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch public: 253345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick SdchDictionaryFetcher(); 263345a6884c488ff3a535c2c9acdd33d74b37e311Iain Merrick virtual ~SdchDictionaryFetcher(); 27c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 2872a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // Stop fetching dictionaries, and abandon any current URLFetcheer operations 2972a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen // so that the IO thread can be stopped. 3072a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen static void Shutdown(); 3172a454cd3513ac24fbdd0e0cb9ad70b86a99b801Kristian Monsen 32c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Implementation of SdchFetcher class. 33c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // This method gets the requested dictionary, and then calls back into the 34c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // SdchManager class with the dictionary's text. 35c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch virtual void Schedule(const GURL& dictionary_url); 36c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 37c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch private: 38c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Delay in ms between Schedule and actual download. 39c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // This leaves the URL in a queue, which is de-duped, so that there is less 40c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // chance we'll try to load the same URL multiple times when a pile of 41c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // page subresources (or tabs opened in parallel) all suggest the dictionary. 42c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch static const int kMsDelayFromRequestTillDownload = 100; 43c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 44c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Ensure the download after the above delay. 45c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void ScheduleDelayedRun(); 46c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 47c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Make sure we're processing (or waiting for) the the arrival of the next URL 48c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // in the |fetch_queue_|. 49c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch void StartFetching(); 50c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 51c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Implementation of URLFetcher::Delegate. Called after transmission 52c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // completes (either successfully or with failure). 53c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch virtual void OnURLFetchComplete(const URLFetcher* source, 54c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch const GURL& url, 553f50c38dc070f4bb515c1b64450dae14f316474eKristian Monsen const net::URLRequestStatus& status, 56c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch int response_code, 57c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch const ResponseCookies& cookies, 58c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch const std::string& data); 59c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 60c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // A queue of URLs that are being used to download dictionaries. 61c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch std::queue<GURL> fetch_queue_; 62c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // The currently outstanding URL fetch of a dicitonary. 63c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // If this is null, then there is no outstanding request. 64c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch scoped_ptr<URLFetcher> current_fetch_; 65c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 66c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Always spread out the dictionary fetches, so that they don't steal 67c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // bandwidth from the actual page load. Create delayed tasks to spread out 68c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // the download. 69c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch ScopedRunnableMethodFactory<SdchDictionaryFetcher> method_factory_; 70c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch bool task_is_pending_; 71c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 72c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // Althought the SDCH spec does not preclude a server from using a single URL 73c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // to load several distinct dictionaries (by telling a client to load a 74c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // dictionary from an URL several times), current implementations seem to have 75c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // that 1-1 relationship (i.e., each URL points at a single dictionary, and 76c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // the dictionary content does not change over time, and hence is not worth 77c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // trying to load more than once). In addition, some dictionaries prove 78c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // unloadable only after downloading them (because they are too large? ...or 79c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // malformed?). As a protective element, Chromium will *only* load a 80c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // dictionary at most once from a given URL (so that it doesn't waste 81c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // bandwidth trying repeatedly). 82c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // The following set lists all the dictionary URLs that we've tried to load, 83c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // so that we won't try to load from an URL more than once. 84c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch // TODO(jar): Try to augment the SDCH proposal to include this restiction. 85c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch std::set<GURL> attempted_load_; 86c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 87c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch DISALLOW_COPY_AND_ASSIGN(SdchDictionaryFetcher); 88c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch}; 89c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch 90c407dc5cd9bdc5668497f21b26b09d988ab439deBen Murdoch#endif // CHROME_BROWSER_NET_SDCH_DICTIONARY_FETCHER_H_ 91