Create a histogram serialization mechanism in components/metrics

components/metrics/chromeos/serialization_utils_unittest.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "components/metrics/chromeos/serialization_utils.h"
+
+#include "base/file_util.h"
+#include "base/files/scoped_temp_dir.h"
+#include "base/logging.h"
+#include "base/strings/stringprintf.h"
+#include "components/metrics/chromeos/metric_sample.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace metrics {
+namespace {
+
+class SerializationUtilsChromeOSTest : public testing::Test {
+ protected:
+  SerializationUtilsChromeOSTest() {
+    bool success = temporary_dir.CreateUniqueTempDir();
+    if (success) {
+      base::FilePath dir_path = temporary_dir.path();
+      filename = dir_path.value() + "chromeossampletest";
+      filepath = base::FilePath(filename);
+    }
+  }
+
+  virtual void SetUp() OVERRIDE {
+    base::DeleteFile(filepath, false);
+  }
+
+  void TestSerialization(MetricSample* sample) {
+    std::string serialized(sample->ToString());
+    ASSERT_EQ('\0', serialized[serialized.length() - 1]);
+    scoped_ptr<MetricSample> deserialized =
+        SerializationUtils::ParseSample(serialized);
+    ASSERT_TRUE(deserialized);
+    EXPECT_TRUE(sample->IsEqual(*deserialized.get()));
+  }
+
+  std::string filename;
+  base::ScopedTempDir temporary_dir;
+  base::FilePath filepath;
+};
+
+TEST_F(SerializationUtilsChromeOSTest, CrashSerializeTest) {
+  TestSerialization(MetricSample::CrashSample("test").get());
+}
+
+TEST_F(SerializationUtilsChromeOSTest, HistogramSerializeTest) {
+  TestSerialization(
+      MetricSample::HistogramSample("myhist", 13, 1, 100, 10).get());
+}
+
+TEST_F(SerializationUtilsChromeOSTest, LinearSerializeTest) {
+  TestSerialization(
+      MetricSample::LinearHistogramSample("linearhist", 12, 30).get());
+}
+
+TEST_F(SerializationUtilsChromeOSTest, SparseSerializeTest) {
+  TestSerialization(MetricSample::SparseHistogramSample("mysparse", 30).get());
+}
+
+TEST_F(SerializationUtilsChromeOSTest, UserActionSerializeTest) {
+  TestSerialization(MetricSample::UserActionSample("myaction").get());
+}
+
+TEST_F(SerializationUtilsChromeOSTest, IllegalNameAreFilteredTest) {
+  scoped_ptr<MetricSample> sample1 =
+      MetricSample::SparseHistogramSample("no space", 10);
+  scoped_ptr<MetricSample> sample2 = MetricSample::LinearHistogramSample(
+      base::StringPrintf("here%cbhe", '\0'), 1, 3);
+
+  EXPECT_FALSE(SerializationUtils::WriteMetricToFile(*sample1.get(), filename));
+  EXPECT_FALSE(SerializationUtils::WriteMetricToFile(*sample2.get(), filename));
+  int64 size = 0;
+
+  ASSERT_TRUE(!PathExists(filepath) || base::GetFileSize(filepath, &size));
+
+  EXPECT_EQ(0, size);
+}
+
+TEST_F(SerializationUtilsChromeOSTest, BadInputIsCaughtTest) {
+  std::string input(
+      base::StringPrintf("sparsehistogram%cname foo%c", '\0', '\0'));
+  EXPECT_EQ(NULL, MetricSample::ParseSparseHistogram(input).get());
+}
+
+TEST_F(SerializationUtilsChromeOSTest, MessageSeparatedByZero) {
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample("mycrash");
+
+  SerializationUtils::WriteMetricToFile(*crash.get(), filename);
+  int64 size = 0;
+  ASSERT_TRUE(base::GetFileSize(filepath, &size));
+  // 4 bytes for the size
+  // 5 bytes for crash
+  // 7 bytes for mycrash
+  // 2 bytes for the \0
+  // -> total of 18
+  EXPECT_EQ(size, 18);
+}
+
+TEST_F(SerializationUtilsChromeOSTest, MessagesTooLongAreDiscardedTest) {
+  // Creates a message that is bigger than the maximum allowed size.
+  // As we are adding extra character (crash, \0s, etc), if the name is
+  // kMessageMaxLength long, it will be too long.
+  std::string name(SerializationUtils::kMessageMaxLength, 'c');
+
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample(name);
+  EXPECT_FALSE(SerializationUtils::WriteMetricToFile(*crash.get(), filename));
+  int64 size = 0;
+  ASSERT_TRUE(base::GetFileSize(filepath, &size));
+  EXPECT_EQ(0, size);
+}
+
+TEST_F(SerializationUtilsChromeOSTest, ReadLongMessageTest) {
+  base::File test_file(filepath,
+                       base::File::FLAG_OPEN_ALWAYS | base::File::FLAG_APPEND);
+  std::string message(SerializationUtils::kMessageMaxLength + 1, 'c');
+
+  int32 message_size = message.length() + sizeof(int32);
+  test_file.WriteAtCurrentPos(reinterpret_cast<const char*>(&message_size),
+                              sizeof(message_size));
+  test_file.WriteAtCurrentPos(message.c_str(), message.length());
+  test_file.Close();
+
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample("test");
+  SerializationUtils::WriteMetricToFile(*crash.get(), filename);
+
+  ScopedVector<MetricSample> samples;
+  SerializationUtils::ReadAndTruncateMetricsFromFile(filename, &samples);
+  ASSERT_EQ(size_t(1), samples.size());
+  ASSERT_TRUE(samples[0] != NULL);
+  EXPECT_TRUE(crash->IsEqual(*samples[0]));
+}
+
+TEST_F(SerializationUtilsChromeOSTest, WriteReadTest) {
+  scoped_ptr<MetricSample> hist =
+      MetricSample::HistogramSample("myhist", 1, 2, 3, 4);
+  scoped_ptr<MetricSample> crash = MetricSample::CrashSample("mycrash");
+  scoped_ptr<MetricSample> lhist =
+      MetricSample::LinearHistogramSample("linear", 1, 10);
+  scoped_ptr<MetricSample> shist =
+      MetricSample::SparseHistogramSample("mysparse", 30);
+  scoped_ptr<MetricSample> action = MetricSample::UserActionSample("myaction");
+
+  SerializationUtils::WriteMetricToFile(*hist.get(), filename);
+  SerializationUtils::WriteMetricToFile(*crash.get(), filename);
+  SerializationUtils::WriteMetricToFile(*lhist.get(), filename);
+  SerializationUtils::WriteMetricToFile(*shist.get(), filename);
+  SerializationUtils::WriteMetricToFile(*action.get(), filename);
+  ScopedVector<MetricSample> vect;
+  SerializationUtils::ReadAndTruncateMetricsFromFile(filename, &vect);
+  ASSERT_EQ(vect.size(), size_t(5));
+  for (int i = 0; i < 5; i++) {
+    ASSERT_TRUE(vect[0] != NULL);
+  }
+  EXPECT_TRUE(hist->IsEqual(*vect[0]));
+  EXPECT_TRUE(crash->IsEqual(*vect[1]));
+  EXPECT_TRUE(lhist->IsEqual(*vect[2]));
+  EXPECT_TRUE(shist->IsEqual(*vect[3]));
+  EXPECT_TRUE(action->IsEqual(*vect[4]));
+
+  int64 size = 0;
+  ASSERT_TRUE(base::GetFileSize(filepath, &size));
+  ASSERT_EQ(0, size);
+}
+
+}  // namespace
+}  // namespace metrics