[UMA] Use proper C++ objects to serialize tracked_objects across process boundaries.

chrome/browser/task_profiler/task_profiler_data_serializer_unittest.cc

+// Copyright (c) 2012 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 <string>
+
+#include "base/basictypes.h"
+#include "base/json/json_writer.h"
+#include "base/process_util.h"
+#include "base/string_number_conversions.h"
+#include "base/tracked_objects.h"
+#include "base/values.h"
+#include "chrome/browser/task_profiler/task_profiler_data_serializer.h"
+#include "content/public/common/process_type.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace {
+
+std::string GetProcessIdString() {
+  return base::IntToString(base::GetCurrentProcId());
+}
+
+void ExpectSerialization(
+    const tracked_objects::SerializedProcessData& process_data,
+    content::ProcessType process_type,
+    const std::string& expected_json) {
+  base::DictionaryValue serialized_value;
+  task_profiler::TaskProfilerDataSerializer::SerializeToJson(
+      process_data, process_type, &serialized_value);
+
+  std::string serialized_json;
+  base::JSONWriter::Write(&serialized_value, &serialized_json);
+
+  EXPECT_EQ(expected_json, serialized_json);
+}
+
+}  // anonymous namespace
+
+// Tests the JSON serialization format for profiled process data.
+TEST(TaskProfilerDataSerializerTest, SerializeProcessDataToJson) {
+  {
+    // Empty data.
+    tracked_objects::SerializedProcessData process_data;
+    content::ProcessType process_type = content::PROCESS_TYPE_BROWSER;
+    ExpectSerialization(process_data, process_type,
+                        "{"
+                          "\"descendants\":["
+                          "],"
+                          "\"list\":["
+                          "],"
+                          "\"process_id\":" + GetProcessIdString() + ","
+                          "\"process_type\":\"Browser\""
+                        "}");
+  }
+
+  {
+    // Non-empty data.
+    tracked_objects::SerializedProcessData process_data;
+
+    tracked_objects::SerializedBirthOnThread parent;
+    parent.location.file_name = "path/to/foo.cc";
+    parent.location.function_name = "WhizBang";
+    parent.location.line_number = 101;
+    parent.thread_name = "CrBrowserMain";
+
+    tracked_objects::SerializedBirthOnThread child;
+    child.location.file_name = "path/to/bar.cc";
+    child.location.function_name = "FizzBoom";
+    child.location.line_number = 433;
+    child.thread_name = "Chrome_IOThread";
+
+
+    // Add a snapshot.
+    process_data.snapshots.push_back(tracked_objects::SerializedSnapshot());
+    process_data.snapshots.back().birth = parent;
+    process_data.snapshots.back().death_data.count = 37;
+    process_data.snapshots.back().death_data.run_duration_sum = 3;
+    process_data.snapshots.back().death_data.run_duration_max = 17;
+    process_data.snapshots.back().death_data.run_duration_sample = 5;
+    process_data.snapshots.back().death_data.queue_duration_sum = 13;

[jar (doing other things), 2012/04/04 17:55:35]

sums should probably be larger than max or sample values.  It would be tempting
to push asserts into the object... so we may as well "keep it real" in case such
happens.

[Ilya Sherman, 2012/04/05 02:51:04]

Oops, maxes should probably be larger than samples, too.  That's how I'd meant
to set things up, but I guess the variables got swapped around...  Thanks for
catching that!

+    process_data.snapshots.back().death_data.queue_duration_max = 79;
+    process_data.snapshots.back().death_data.queue_duration_sample = 53;
+    process_data.snapshots.back().death_thread_name = "WorkerPool/-1340960768";
+
+    // Add a second snapshot.
+    process_data.snapshots.push_back(tracked_objects::SerializedSnapshot());
+    process_data.snapshots.back().birth = child;
+    process_data.snapshots.back().death_data.count = 41;
+    process_data.snapshots.back().death_data.run_duration_sum = 203;
+    process_data.snapshots.back().death_data.run_duration_max = 2017;
+    process_data.snapshots.back().death_data.run_duration_sample = 205;
+    process_data.snapshots.back().death_data.queue_duration_sum = 2013;
+    process_data.snapshots.back().death_data.queue_duration_max = 2079;
+    process_data.snapshots.back().death_data.queue_duration_sample = 2053;
+    process_data.snapshots.back().death_thread_name = "PAC thread #3";
+
+    // Add a parent-child pair.
+    process_data.descendants.push_back(
+        tracked_objects::SerializedParentChildPair());
+    process_data.descendants.back().parent = parent;
+    process_data.descendants.back().child = child;
+
+    content::ProcessType process_type = content::PROCESS_TYPE_RENDERER;
+    ExpectSerialization(process_data, process_type,
+                       "{"
+                          "\"descendants\":["
+                             "{"
+                               "\"child_location\":{"
+                                  "\"file_name\":\"path/to/bar.cc\","
+                                  "\"function_name\":\"FizzBoom\","
+                                 "\"line_number\":433"
+                               "},"
+                               "\"child_thread\":\"Chrome_IOThread\","
+                               "\"parent_location\":{"
+                                  "\"file_name\":\"path/to/foo.cc\","
+                                  "\"function_name\":\"WhizBang\","
+                                  "\"line_number\":101"
+                               "},"
+                               "\"parent_thread\":\"CrBrowserMain\""
+                             "}"
+                          "],"
+                          "\"list\":[{"
+                             "\"birth_location\":{"
+                                "\"file_name\":\"path/to/foo.cc\","
+                                "\"function_name\":\"WhizBang\","
+                                "\"line_number\":101"
+                             "},"
+                             "\"birth_thread\":\"CrBrowserMain\","
+                             "\"death_data\":{"
+                                "\"count\":37,"
+                                "\"queue_ms\":13,"
+                                "\"queue_ms_max\":79,"
+                                "\"queue_ms_sample\":53,"
+                                "\"run_ms\":3,"
+                                "\"run_ms_max\":17,"
+                                "\"run_ms_sample\":5"
+                             "},"
+                             "\"death_thread\":\"WorkerPool/-1340960768\""
+                          "},{"
+                             "\"birth_location\":{"
+                                "\"file_name\":\"path/to/bar.cc\","
+                                "\"function_name\":\"FizzBoom\","
+                                "\"line_number\":433"
+                             "},"
+                             "\"birth_thread\":\"Chrome_IOThread\","
+                             "\"death_data\":{"
+                                "\"count\":41,"
+                                "\"queue_ms\":2013,"
+                                "\"queue_ms_max\":2079,"
+                                "\"queue_ms_sample\":2053,"
+                                "\"run_ms\":203,"
+                                "\"run_ms_max\":2017,"
+                                "\"run_ms_sample\":205"
+                             "},"
+                             "\"death_thread\":\"PAC thread #3\""
+                          "}],"
+                          "\"process_id\":" + GetProcessIdString() + ","
+                          "\"process_type\":\"Tab\""
+                        "}");
+  }
+}