Form Event message correctly

Previously the Event message for MEET_DEVICE_TELEMETRY was not formed
correctly. This CL forms it correctly and adds some comments to make it
easier to understand.

Bug: chromium:1078512 b:169427520
Change-Id: Ic6af71cebaf15c37f43dea54f9b4eff9d6ba1e4a
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2468836
Commit-Queue: Zach Trudo <zatrudo@google.com>
Reviewed-by: Leonid Baraz <lbaraz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#816727}

chrome/browser/policy/messaging_layer/upload/meet_device_telemetry_report_handler.cc

@@ -32,15 +32,33 @@ namespace reporting {
 
 namespace {
 
-// Common Key names used when building the dictionary to pass to the Chrome
-// Reporting API.
+// Common Key names used when building the Event dictionary to pass to the
+// Chrome Reporting API.
+// When sent the event should look like this:
+// {
+//   "time": "2017-01-15T01:30:15.01Z", // Timestamp in RFC3339 format
+//   "reportingRecordEvent": {
+//     "destination": 3,
+//     "dmToken": "abcdef1234",
+//     "timestampUs"": 123456,
+//     "data": "String of Data"
+//   }
+// }
+constexpr char kTime[] = "time";
+constexpr char kReportingRecordEvent[] = "reportingRecordEvent";
+
+// Common key names used when builing the ReportingRecordEvent dictionary to
+// pass to Chrome Reporting API. This is the dictionary indicated by
+// |kReportingRecordEvent|. This dictionary is a direct 1:1 relation to the
+// reporting::Record proto.
 constexpr char kDestination[] = "destination";
 constexpr char kDmToken[] = "dmToken";
 constexpr char kTimestampUs[] = "timestampUs";
 constexpr char kData[] = "data";
 
-base::Value ConvertRecordProtoToValue(const Record& record,
-                                      const base::Value& context) {
+// Takes a reporting::Record and converts it to the |kReportingRecordEvent|
+// dictionary.
+base::Value ConvertRecordProtoToValue(const Record& record) {
   base::Value record_fields{base::Value::Type::DICTIONARY};
   if (record.has_destination()) {
     record_fields.SetIntKey(kDestination, record.destination());
@@ -58,8 +76,39 @@ base::Value ConvertRecordProtoToValue(const Record& record,
   if (record.has_data()) {  // No data indicates gap, empty data is still data.
     record_fields.SetStringKey(kData, record.data());
   }
+  return record_fields;
+}
+
+// Generates a RFC3999 time string.
+std::string GetTimeString(const base::Time& timestamp) {
+  base::Time::Exploded time_exploded;
+  timestamp.UTCExplode(&time_exploded);
+  std::string time_str = base::StringPrintf(
+      "%d-%02d-%02dT%02d:%02d:%02d.%03dZ", time_exploded.year,
+      time_exploded.month, time_exploded.day_of_month, time_exploded.hour,
+      time_exploded.minute, time_exploded.second, time_exploded.millisecond);
+  return time_str;
+}
+
+// Creates a list of Event dictionaries from a Record. (Note: Currently takes
+// one Record and makes a list with one Event).
+base::Value ConvertRecordProtoToEventList(const Record& record) {
+  // Create the Event Dictionary
+  base::Value event{base::Value::Type::DICTIONARY};
+
+  // Set the |kReportingRecordEvent| key to the Record dictionary.
+  event.SetKey(kReportingRecordEvent, ConvertRecordProtoToValue(record));
+
+  // Build the timestamp and set the |kTime| to the RFC3999 version.
+  base::Time timestamp =
+      base::Time::UnixEpoch() +
+      base::TimeDelta::FromMicroseconds(record.timestamp_us());
+  event.SetStringKey(kTime, GetTimeString(timestamp));
+
+  // Build the list and append the event.
   base::Value records_list{base::Value::Type::LIST};
-  records_list.Append(std::move(record_fields));
+  records_list.Append(std::move(event));
+
   return records_list;
 }
 
@@ -85,7 +134,7 @@ Status MeetDeviceTelemetryReportHandler::ValidateRecord(
 StatusOr<base::Value> MeetDeviceTelemetryReportHandler::ConvertRecord(
     const Record& record) const {
   base::Value context = reporting::GetContext(profile_);
-  base::Value event_list = ConvertRecordProtoToValue(record, context);
+  base::Value event_list = ConvertRecordProtoToEventList(record);
   return policy::RealtimeReportingJobConfiguration::BuildReport(
       std::move(event_list), std::move(context));
 }

chrome/browser/policy/messaging_layer/upload/meet_device_telemetry_report_handler_unittest.cc

@@ -45,13 +45,20 @@ MATCHER_P(MatchValue, expected, "matches base::Value") {
     return false;
   }
   const base::Value& event = *events_list.begin();
-  const auto destination = event.FindIntKey("destination");
+
+  const auto* reporting_record_event = event.FindKey("reportingRecordEvent");
+  if (reporting_record_event == nullptr) {
+    LOG(ERROR) << "'reportingRecordEvent' is missing" << event;
+    return false;
+  }
+
+  const auto destination = reporting_record_event->FindIntKey("destination");
   if (!destination.has_value() ||
       destination.value() != Destination::MEET_DEVICE_TELEMETRY) {
     LOG(ERROR) << "'destination' is wrong or missing";
     return false;
   }
-  const std::string* const data = event.FindStringKey("data");
+  const std::string* const data = reporting_record_event->FindStringKey("data");
   if (!data) {
     LOG(ERROR) << "'data' is missing";
     return false;