Compress and checksum pending logs that are going to be persisted. ...

chrome/browser/metrics/metrics_service_unittest.cc

Index: chrome/browser/metrics/metrics_service_unittest.cc
===================================================================
--- chrome/browser/metrics/metrics_service_unittest.cc	(revision 52082)
+++ chrome/browser/metrics/metrics_service_unittest.cc	(working copy)
@@ -5,6 +5,11 @@
 #include "chrome/browser/metrics/metrics_service.h"
 
 #include <string>
+#include <vector>
+
+#include "base/base64.h"
+#include "base/md5.h"
+
 #include "testing/gtest/include/gtest/gtest.h"
 
 #if defined(OS_POSIX) && defined(LINUX2)
@@ -43,3 +48,177 @@
   EXPECT_EQ("unknown", hardware_class);
 }
 #endif  // OS_CHROMEOS
+
+class MetricsServiceTest : public ::testing::Test {
+};
+
+static const size_t kMaxLocalListSize = 3;
+
+// Store and retrieve empty list.
+TEST(MetricsServiceTest, EmptyLogList) {
+  ListValue list;
+  std::vector<std::string> local_list;
+
+  MetricsService::StoreUnsentLogsHelper(local_list, kMaxLocalListSize, &list);
+  EXPECT_EQ(0U, list.GetSize());
+
+  local_list.clear();  // RecallUnsentLogsHelper() expects empty |local_list|.
+  EXPECT_EQ(MetricsService::LIST_EMPTY,
+            MetricsService::RecallUnsentLogsHelper(list, &local_list));
+  EXPECT_EQ(0U, local_list.size());
+}
+
+// Store and retrieve a single log value.
+TEST(MetricsServiceTest, SingleElementLogList) {
+  ListValue list;
+  std::vector<std::string> local_list;
+
+  local_list.push_back("Hello world!");
+  EXPECT_EQ(1U, local_list.size());
+
+  MetricsService::StoreUnsentLogsHelper(local_list, kMaxLocalListSize, &list);
+
+  // |list| will now contain the following:
+  // [1, Base64Encode("Hello world!"), MD5("Hello world!")].
+  EXPECT_EQ(3U, list.GetSize());
+
+  // Examine each element.
+  ListValue::const_iterator it = list.begin();
+  int size = 0;
+  (*it)->GetAsInteger(&size);
+  EXPECT_EQ(1, size);
+
+  ++it;
+  std::string str;
+  (*it)->GetAsString(&str);  // Base64 encoded "Hello world!" string.
+  std::string encoded;
+  base::Base64Encode("Hello world!", &encoded);
+  EXPECT_TRUE(encoded == str);
+
+  ++it;
+  (*it)->GetAsString(&str);  // MD5 for encoded "Hello world!" string.
+  EXPECT_TRUE(MD5String(encoded) == str);
+
+  ++it;
+  EXPECT_TRUE(it == list.end());  // Reached end of list.
+
+  local_list.clear();
+  EXPECT_EQ(MetricsService::RECALL_SUCCESS,
+            MetricsService::RecallUnsentLogsHelper(list, &local_list));
+  EXPECT_EQ(1U, local_list.size());
+}
+
+// Store elements greater than the limit.
+TEST(MetricsServiceTest, OverLimitLogList) {
+  ListValue list;
+  std::vector<std::string> local_list;
+
+  local_list.push_back("one");
+  local_list.push_back("two");
+  local_list.push_back("three");
+  local_list.push_back("four");
+  EXPECT_EQ(4U, local_list.size());
+
+  std::string expected_first;
+  base::Base64Encode(local_list[local_list.size() - kMaxLocalListSize],
+                     &expected_first);
+  std::string expected_last;
+  base::Base64Encode(local_list[local_list.size() - 1],
+                     &expected_last);
+
+  MetricsService::StoreUnsentLogsHelper(local_list, kMaxLocalListSize, &list);
+  EXPECT_EQ(kMaxLocalListSize + 2, list.GetSize());
+
+  std::string actual_first;
+  EXPECT_TRUE((*(list.begin() + 1))->GetAsString(&actual_first));
+  EXPECT_TRUE(expected_first == actual_first);
+
+  std::string actual_last;
+  EXPECT_TRUE((*(list.end() - 2))->GetAsString(&actual_last));
+  EXPECT_TRUE(expected_last == actual_last);
+
+  local_list.clear();
+  EXPECT_EQ(MetricsService::RECALL_SUCCESS,
+            MetricsService::RecallUnsentLogsHelper(list, &local_list));
+  EXPECT_EQ(kMaxLocalListSize, local_list.size());
+}
+
+// Induce LIST_SIZE_TOO_SMALL corruption
+TEST(MetricsServiceTest, SmallRecoveredListSize) {
+  ListValue list;
+  std::vector<std::string> local_list;
+
+  local_list.push_back("Hello world!");
+  EXPECT_EQ(1U, local_list.size());
+  MetricsService::StoreUnsentLogsHelper(local_list, kMaxLocalListSize, &list);
+  EXPECT_EQ(3U, list.GetSize());
+
+  // Remove last element.
+  list.Remove(list.GetSize() - 1, NULL);
+  EXPECT_EQ(2U, list.GetSize());
+
+  local_list.clear();
+  EXPECT_EQ(MetricsService::LIST_SIZE_TOO_SMALL,
+            MetricsService::RecallUnsentLogsHelper(list, &local_list));
+}
+
+// Remove size from the stored list.
+TEST(MetricsServiceTest, RemoveSizeFromLogList) {
+  ListValue list;
+  std::vector<std::string> local_list;
+
+  local_list.push_back("one");
+  local_list.push_back("two");
+  EXPECT_EQ(2U, local_list.size());
+  MetricsService::StoreUnsentLogsHelper(local_list, kMaxLocalListSize, &list);
+  EXPECT_EQ(4U, list.GetSize());
+
+  list.Remove(0, NULL);  // Delete size (1st element).
+  EXPECT_EQ(3U, list.GetSize());
+
+  local_list.clear();
+  EXPECT_EQ(MetricsService::LIST_SIZE_MISSING,
+            MetricsService::RecallUnsentLogsHelper(list, &local_list));
+}
+
+// Corrupt size of stored list.
+TEST(MetricsServiceTest, CorruptSizeOfLogList) {
+  ListValue list;
+  std::vector<std::string> local_list;
+
+  local_list.push_back("Hello world!");
+  EXPECT_EQ(1U, local_list.size());
+  MetricsService::StoreUnsentLogsHelper(local_list, kMaxLocalListSize, &list);
+  EXPECT_EQ(3U, list.GetSize());
+
+  // Change list size from 1 to 2.
+  EXPECT_TRUE(list.Set(0, Value::CreateIntegerValue(2)));
+  EXPECT_EQ(3U, list.GetSize());
+
+  local_list.clear();
+  EXPECT_EQ(MetricsService::LIST_SIZE_CORRUPTION,
+            MetricsService::RecallUnsentLogsHelper(list, &local_list));
+}
+
+// Corrupt checksum of stored list.
+TEST(MetricsServiceTest, CorruptChecksumOfLogList) {
+  ListValue list;
+  std::vector<std::string> local_list;
+
+  local_list.clear();
+  local_list.push_back("Hello world!");
+  EXPECT_EQ(1U, local_list.size());
+  MetricsService::StoreUnsentLogsHelper(local_list, kMaxLocalListSize, &list);
+  EXPECT_EQ(3U, list.GetSize());
+
+  // Fetch checksum (last element) and change it.
+  std::string checksum;
+  EXPECT_TRUE((*(list.end() - 1))->GetAsString(&checksum));
+  checksum[0] = (checksum[0] == 'a') ? 'b' : 'a';
+  EXPECT_TRUE(list.Set(2, Value::CreateStringValue(checksum)));
+  EXPECT_EQ(3U, list.GetSize());
+
+  local_list.clear();
+  EXPECT_EQ(MetricsService::CHECKSUM_CORRUPTION,
+            MetricsService::RecallUnsentLogsHelper(list, &local_list));
+}