components/rappor/sampler_unittest.cc

   1 // Copyright 2015 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 #include "components/rappor/sampler.h"
   6
   7 #include "components/rappor/byte_vector_utils.h"
   8 #include "components/rappor/proto/rappor_metric.pb.h"
   9 #include "testing/gtest/include/gtest/gtest.h"
  10
  11 namespace rappor {
  12
  13 const RapporParameters kTestRapporParameters = {
  14     1 /* Num cohorts */,
  15     1 /* Bloom filter size bytes */,
  16     4 /* Bloom filter hash count */,
  17     PROBABILITY_75 /* Fake data probability */,
  18     PROBABILITY_50 /* Fake one probability */,
  19     PROBABILITY_75 /* One coin probability */,
  20     PROBABILITY_50 /* Zero coin probability */,
  21     UMA_RAPPOR_GROUP /* Recording group (not used) */};
  22
  23 class TestSamplerFactory {
  24  public:
  25   static scoped_ptr<Sample> CreateSample() {
  26     return scoped_ptr<Sample>(new Sample(0, kTestRapporParameters));
  27   }
  28 };
  29
  30 namespace internal {
  31
  32 // Test that exporting deletes samples.
  33 TEST(RapporSamplerTest, TestExport) {
  34   Sampler sampler;
  35
  36   scoped_ptr<Sample> sample1 = TestSamplerFactory::CreateSample();
  37   sample1->SetStringField("Foo", "Junk");
  38   sampler.AddSample("Metric1", sample1.Pass());
  39
  40   scoped_ptr<Sample> sample2 = TestSamplerFactory::CreateSample();
  41   sample2->SetStringField("Foo", "Junk2");
  42   sampler.AddSample("Metric1", sample2.Pass());
  43
  44   // Since the two samples were for one metric, we should randomly get one
  45   // of the two.
  46   RapporReports reports;
  47   std::string secret = HmacByteVectorGenerator::GenerateEntropyInput();
  48   sampler.ExportMetrics(secret, &reports);
  49   EXPECT_EQ(1, reports.report_size());
  50   EXPECT_EQ(1u, reports.report(0).bits().size());
  51
  52   // First export should clear the metric.
  53   RapporReports reports2;
  54   sampler.ExportMetrics(secret, &reports2);
  55   EXPECT_EQ(0, reports2.report_size());
  56 }
  57
  58 }  // namespace internal
  59
  60 }  // namespace rappor