Google Trace Event Format Metrics

//! The logger is created from a compile time hash of the "SampleEventLogger" string using the FNV-1a 64 bit algorithm
constexpr AZ::Metrics::EventLoggerId SampleLoggerId{ static_cast<AZ::u32>(AZStd::hash<AZStd::string_view>{}("SampleEventLogger")) };

//! This is a google test fixture class used for illustration purposes of recording using the Event Logger API
class JsonTraceEventLoggerTest
    : public ::UnitTest::ScopedAllocatorSetupFixture
{
public:
    JsonTraceEventLoggerTest()
    {
        // Create an event logger factory
        m_eventLoggerFactory = AZStd::make_unique<AZ::Metrics::EventLoggerFactoryImpl>();

        // Register it as a global instance
        AZ::Metrics::EventLoggerFactory::Register(m_eventLoggerFactory.get());

        //...
    }

protected:
    AZStd::string m_metricsOutput;
    AZStd::unique_ptr<AZ::Metrics::IEventLoggerFactory> m_eventLoggerFactory;
};

    JsonTraceEventLoggerTest()
    {
        //... Previous logic to register event factory

        // Create an byte container stream that allows event logger output to be logged in-memory
        auto metricsStream = AZStd::make_unique<AZ::IO::ByteContainerStream<AZStd::string>>(&m_metricsOutput);
        // Create the trace event logger that logs to the Google Trace Event format
        auto eventLogger = AZStd::make_unique<AZ::Metrics::JsonTraceEventLogger>(AZStd::move(metricsStream));

        // Register the Google Trace Event Logger with the Event Logger Factory
        auto registerOutcome = m_eventLoggerFactory->RegisterEventLogger(SampleLoggerId, AZStd::move(eventLogger));
        // Validate that the registration of the factory succeeded
        EXPECT_TRUE(registerOutcome);
    }

{
    constexpr AZStd::string_view eventString = "Hello world";
    constexpr AZ::s64 eventInt64 = -2;


    // Populate the "args" container to associate with each events "args" field
    AZ::Metrics::EventObjectStorage argsContainer;
    argsContainer.emplace_back("string", eventString);
    argsContainer.emplace_back("int64_t", eventInt64);

    {
        // Record Duration Begin and End Events
        AZ::Metrics::DurationArgs durationArgs;
        durationArgs.m_name = "Duration Event";
        durationArgs.m_cat = "Test";
        durationArgs.m_args = argsContainer;
        durationArgs.m_id = "0";
        auto resultOutcome = AZ::Metrics::RecordEvent(SampleLoggerId, AZ::Metrics::EventPhase::DurationBegin, durationArgs);
        EXPECT_TRUE(resultOutcome);

        // Update the string value to "GoodbyeWorld and the integer value to "400"
        argsContainer[0].m_value = "Goodbye world";
        argsContainer[1]= 400;

        // Re-update the durationArgs argument container to have the latetst argument values
        durationArgs.m_args = argsContainer;

        resultOutcome = AZ::Metrics::RecordEvent(SampleLoggerId, AZ::Metrics::EventPhase::DurationEnd, durationArgs);
        EXPECT_TRUE(resultOutcome);
    }
}

{
    constexpr AZ::IO::OpenMode openMode = AZ::IO::OpenMode::ModeWrite;
    auto metricsFilepath = AZ::IO::FixedMaxPath(AZ::Utils::GetProjectUserPath()) / "metrics/sample_metrics_";
    //! Append a ISO 8601 timestamp to the metrics filename to make it unique across runs
    AZ::Date::Iso8601TimestampString currentUtcTimestamp;
    AZ::Date::GetFilenameCompatibleFormatNowWithMicroseconds(currentUtcTimestamp)
    metricsFilepath.Native() += currentUtcTimestamp;
    metricsFilepath.Native() += ".json";

    AZ::IO::SystemFileStream systemFileStream(metricsFilepath.c_str(), openMode);
    // The metrics were written to the ByteContainerStream which was backed by the @m_metricsOutput member
    systemFileStream.Write(m_metricsOutput.size(), m_metricsOutput.c_str());
}

[
  {"name":"Duration Event","id":"0","cat":"Test","ph":"B","ts":1664329933375019,"pid":31760,"tid":36036,"args":{"string":"Hello world","int64_t":-2}},
  {"name":"Duration Event","id":"0","cat":"Test","ph":"E","ts":1664329933375119,"pid":31760,"tid":36036,"args":{"string":"Goodbye world","int64_t":400}}
]