content/browser/attribution_reporting/destination_throttler.h

// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CONTENT_BROWSER_ATTRIBUTION_REPORTING_DESTINATION_THROTTLER_H_
#define CONTENT_BROWSER_ATTRIBUTION_REPORTING_DESTINATION_THROTTLER_H_

#include <map>

#include "base/time/time.h"
#include "content/common/content_export.h"

namespace net {
class SchemefulSite;
}

namespace attribution_reporting {
class DestinationSet;
}

namespace content {

// DestinationThrottler is a class which manages a rolling time window
// keeping track of unique destinations being registered on source sites.
class CONTENT_EXPORT DestinationThrottler {
 public:
  struct Policy {
    int max_total = 200;
    int max_per_reporting_site = 50;
    base::TimeDelta rate_limit_window = base::Minutes(1);
  };
  explicit DestinationThrottler(Policy policy);
  ~DestinationThrottler();

  DestinationThrottler(DestinationThrottler&) = delete;
  DestinationThrottler& operator=(DestinationThrottler&) = delete;

  // Returns true if the throttler allowed `destinations` through. Also updates
  // the internal state of the throttler to track all of the passed
  // destinations.
  [[nodiscard]] bool UpdateAndGetAllowed(
      const attribution_reporting::DestinationSet& destinations,
      const net::SchemefulSite& source_site,
      const net::SchemefulSite& reporting_site);

 private:
  void CleanUpOldEntries();

  class SourceSiteData;
  std::map<net::SchemefulSite, SourceSiteData> source_site_data_;
  Policy policy_;
};

}  // namespace content

#endif  // CONTENT_BROWSER_ATTRIBUTION_REPORTING_DESTINATION_THROTTLER_H_