blob: 8dcbfa4fdd1a908b4b6846b34700d297d35c36f4 [file] [log] [blame]
// 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.
#include <string>
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_ptr.h"
#include "base/memory/weak_ptr.h"
#include "chrome/browser/web_resource/json_asynchronous_unpacker.h"
#include "chrome/browser/web_resource/resource_request_allowed_notifier.h"
#include "net/url_request/url_fetcher_delegate.h"
#include "url/gurl.h"
class PrefService;
namespace base {
class DictionaryValue;
namespace net {
class URLFetcher;
// A WebResourceService fetches JSON data from a web server and periodically
// refreshes it.
class WebResourceService
: public net::URLFetcherDelegate,
public JSONAsynchronousUnpackerDelegate,
public base::RefCountedThreadSafe<WebResourceService>,
public ResourceRequestAllowedNotifier::Observer {
WebResourceService(PrefService* prefs,
const GURL& web_resource_server,
bool apply_locale_to_url_,
const char* last_update_time_pref_name,
int start_fetch_delay_ms,
int cache_update_delay_ms);
// Sleep until cache needs to be updated, but always for at least
// |start_fetch_delay_ms| so we don't interfere with startup.
// Then begin updating resources.
void StartAfterDelay();
// JSONAsynchronousUnpackerDelegate methods.
virtual void OnUnpackFinished(
const base::DictionaryValue& parsed_json) OVERRIDE;
virtual void OnUnpackError(const std::string& error_message) OVERRIDE;
virtual ~WebResourceService();
// For the subclasses to process the result of a fetch.
virtual void Unpack(const base::DictionaryValue& parsed_json) = 0;
PrefService* prefs_;
class UnpackerClient;
friend class base::RefCountedThreadSafe<WebResourceService>;
// net::URLFetcherDelegate implementation:
virtual void OnURLFetchComplete(const net::URLFetcher* source) OVERRIDE;
// Schedules a fetch after |delay_ms| milliseconds.
void ScheduleFetch(int64 delay_ms);
// Starts fetching data from the server.
void StartFetch();
// Set |in_fetch_| to false, clean up temp directories (in the future).
void EndFetch();
// Implements ResourceRequestAllowedNotifier::Observer.
virtual void OnResourceRequestsAllowed() OVERRIDE;
// Helper class used to tell this service if it's allowed to make network
// resource requests.
ResourceRequestAllowedNotifier resource_request_allowed_notifier_;
// The tool that fetches the url data from the server.
scoped_ptr<net::URLFetcher> url_fetcher_;
// The tool that parses and transforms the json data. Weak reference as it
// deletes itself once the unpack is done.
JSONAsynchronousUnpacker* json_unpacker_;
// True if we are currently fetching or unpacking data. If we are asked to
// start a fetch when we are still fetching resource data, schedule another
// one in |cache_update_delay_ms_| time, and silently exit.
bool in_fetch_;
// URL that hosts the web resource.
GURL web_resource_server_;
// Indicates whether we should append locale to the web resource server URL.
bool apply_locale_to_url_;
// Pref name to store the last update's time.
const char* last_update_time_pref_name_;
// Delay on first fetch so we don't interfere with startup.
int start_fetch_delay_ms_;
// Delay between calls to update the web resource cache. This delay may be
// different for different builds of Chrome.
int cache_update_delay_ms_;
// So that we can delay our start so as not to affect start-up time; also,
// so that we can schedule future cache updates.
base::WeakPtrFactory<WebResourceService> weak_ptr_factory_;