chromium/net/dns/httpssvc_metrics.h

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef NET_DNS_HTTPSSVC_METRICS_H_
#define NET_DNS_HTTPSSVC_METRICS_H_

#include <optional>
#include <string>
#include <string_view>
#include <vector>

#include "base/containers/flat_set.h"
#include "base/time/time.h"
#include "net/base/net_export.h"

namespace net {

// These values are persisted to logs. Entries should not be renumbered and
// numeric values should never be reused. (See HttpssvcDnsRcode in
// tools/metrics/histograms/enums.xml.)
enum HttpssvcDnsRcode { … };

// Translate an RCODE value to the |HttpssvcDnsRcode| enum, which is used for
// HTTPSSVC experimentation. The goal is to keep these values in a small,
// contiguous range in order to satisfy the UMA enumeration function's
// requirements. This function never returns |kTimedOut| |kUnrecognizedRcode|,
// or |kMissingDnsResponse|.
enum HttpssvcDnsRcode TranslateDnsRcodeForHttpssvcExperiment(uint8_t rcode);

// Tool for aggregating HTTPS RR metrics. Accumulates metrics via the Save*
// methods. Records metrics to UMA on destruction.
// TODO(crbug.com/40239736): Rework this class once we've finished with
// HTTPS-related rollouts and have decided what metrics we want to keep
// permanently.
class NET_EXPORT_PRIVATE HttpssvcMetrics { … };

}  // namespace net

#endif  // NET_DNS_HTTPSSVC_METRICS_H_