rappor_parameters.h revision cedac228d2dd51db4b79ea1e72c7f249408ee061 
1// Copyright 2014 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#ifndef COMPONENTS_RAPPOR_RAPPOR_PARAMETERS_H_
6#define COMPONENTS_RAPPOR_RAPPOR_PARAMETERS_H_
7
8#include <string>
9
10namespace rappor {
11
12enum Probability {
13  PROBABILITY_75,    // 75%
14  PROBABILITY_50,    // 50%
15  PROBABILITY_25,    // 25%
16};
17
18// An object describing a rappor metric and the parameters used to generate it.
19//
20// For a full description of the rappor metrics, see
21// http://www.chromium.org/developers/design-documents/rappor
22struct RapporParameters {
23  // Get a string representing the parameters, for DCHECK_EQ.
24  std::string ToString() const;
25
26  // The maximum number of cohorts we divide clients into.
27  static const int kMaxCohorts;
28
29  // The number of cohorts to divide the reports for this metric into.
30  int num_cohorts;
31
32  // The number of bytes stored in the Bloom filter.
33  int bloom_filter_size_bytes;
34  // The number of hash functions used in the Bloom filter.
35  int bloom_filter_hash_function_count;
36
37  // The probability that a bit will be redacted with fake data.
38  Probability fake_prob;
39  // The probability that a fake bit will be a one.
40  Probability fake_one_prob;
41
42  // The probability that a one bit in the redacted data reports as one.
43  Probability one_coin_prob;
44  // The probability that a zero bit in the redacted data reports as one.
45  Probability zero_coin_prob;
46};
47
48}  // namespace rappor
49
50#endif  // COMPONENTS_RAPPOR_RAPPOR_PARAMETERS_H_
51