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content / browser / interest_group / ad_auction_result_metrics.h [blame]
// Copyright 2021 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_INTEREST_GROUP_AD_AUCTION_RESULT_METRICS_H_
#define CONTENT_BROWSER_INTEREST_GROUP_AD_AUCTION_RESULT_METRICS_H_
#include <climits>
#include "base/numerics/clamped_math.h"
#include "base/time/time.h"
#include "content/public/browser/page_user_data.h"
namespace content {
class Page;
// Reports UMA about success / failure auction patterns, and implements a
// feature parameter to control the maximum number of auctions per-page.
class AdAuctionResultMetrics
: public content::PageUserData<AdAuctionResultMetrics> {
public:
enum class AuctionResult { kSucceeded, kFailed };
explicit AdAuctionResultMetrics(content::Page& page);
~AdAuctionResultMetrics() override;
// To reduce the amount of information that may be exposed to the page from
// auction outcomes, the number of auctions per page may be limited by a
// feature parameter.
//
// Before starting an auction, this function should be consulted to check if
// this limit has already been encountered.
//
// This function should be called only once per auction attempt, since it
// modifies internal state.
bool ShouldRunAuction();
// After an auction as completed, this function should be called to report
// whether the auction succeeded or failed.
//
// This function should *not* be called for configuration failures where the
// auction result reveals no information about stored interest groups.
void ReportAuctionResult(AuctionResult result);
private:
// Number of bits to record for the first N auctions, including a leading 1.
// That is, kNumFirstAuctionBits - 1 auctions will be recorded. Increasing
// this number will increase the number of UMA buckets, so don't set it too
// high.
static constexpr int kNumFirstAuctionBits = 7;
// The number of calls to ShouldRunAuction(); used for enforcing auction
// limits.
base::ClampedNumeric<int> num_requested_auctions_ = 0;
// The number of auctions that ran to completion, successful and failed --
// this is also the number of ReportAuctionResult() calls.
base::ClampedNumeric<int> num_completed_auctions_ = 0;
// The number of auctions that ran to completion and succeeded.
base::ClampedNumeric<int> num_successful_auctions_ = 0;
// The number of auctions requested that didn't run because the page auction
// limit had been reached. Should equal num_requested_auctions_ -
// num_completed_auctions_, which is DCHECK'd on destruction.
base::ClampedNumeric<int> num_auctions_not_run_due_to_auction_limit_ = 0;
// Stores the bitfield of the first kNumFirstAuctionBits auction results.
uint8_t first_auction_bits_ = 1u;
// Stores the time of the last completed auction.
base::TimeTicks last_auction_time_ = base::TimeTicks::Min();
static_assert(kNumFirstAuctionBits <=
sizeof(AdAuctionResultMetrics::first_auction_bits_) *
CHAR_BIT,
"Not enough bits in `first_auction_bits_`.");
friend PageUserData;
PAGE_USER_DATA_KEY_DECL();
};
} // namespace content
#endif // CONTENT_BROWSER_INTEREST_GROUP_AD_AUCTION_RESULT_METRICS_H_