quota_service.h | Explore in Territory

// Copyright 2013 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// The QuotaService uses heuristics to limit abusive requests
// made by extensions.  In this model 'items' (e.g individual bookmarks) are
// represented by a 'Bucket' that holds state for that item for one single
// interval of time.  The interval of time is defined as 'how long we need to
// watch an item (for a particular heuristic) before making a decision about
// quota violations'.  A heuristic is two functions: one mapping input
// arguments to a unique Bucket (the BucketMapper), and another to determine
// if a new request involving such an item at a given time is a violation.

#ifndef EXTENSIONS_BROWSER_QUOTA_SERVICE_H_
#define EXTENSIONS_BROWSER_QUOTA_SERVICE_H_

#include <stdint.h>

#include <list>
#include <map>
#include <memory>
#include <string>

#include "base/threading/thread_checker.h"
#include "base/time/time.h"
#include "base/timer/timer.h"
#include "base/values.h"
#include "extensions/common/extension_id.h"

class ExtensionFunction;

namespace extensions {
class QuotaLimitHeuristic;

QuotaLimitHeuristics;

// The QuotaService takes care that calls to certain extension
// functions do not exceed predefined quotas.
//
// The QuotaService needs to live entirely on one thread, i.e. be created,
// called and destroyed on the same thread, due to its use of a RepeatingTimer.
// It is not a KeyedService because instances exist on both the UI
// and IO threads.
class QuotaService { … };

// A QuotaLimitHeuristic is two things: 1, A heuristic to map extension
// function arguments to corresponding Buckets for each input arg, and 2) a
// heuristic for determining if a new event involving a particular item
// (represented by its Bucket) constitutes a quota violation.
class QuotaLimitHeuristic { … };

// A simple per-item heuristic to limit the number of events that can occur in
// a given period of time; e.g "no more than 100 events in an hour".
class QuotaService::TimedLimit : public QuotaLimitHeuristic { … };

}  // namespace extensions

#endif  // EXTENSIONS_BROWSER_QUOTA_SERVICE_H_
chromium/extensions/browser/quota_service.h
