NR-480384: Add QOE metrics

[swatijha23]

KPIs are calculated based on this doc - https://newrelic.atlassian.net/wiki/spaces/VERTSOL/pages/4702274467/KPIs+Transformation+QOE+Score

1. kpi.startupTime
   kpi.startupTime = timeSinceRequested
   Source: TimeSince mechanism tracking time from CONTENT_REQUEST to current moment

2. kpi.peakBitrate
   Formula: Maximum value tracking
   kpi.peakBitrate = MAX(bitrate_1, bitrate_2, ..., bitrate_n)

3. kpi.hadStartupFailure

Formula: Boolean logic based on playback state
kpi.hadStartupFailure = (timeSinceStarted == null)

Logic:

• true = Error occurred before CONTENT_START (no timeSinceStarted attribute exists)
• false = Playback started successfully

4. kpi.hadPlaybackFailure

Formula: Boolean flag set on error during playback
kpi.hadPlaybackFailure = qoeHadPlaybackFailure

Tracking Logic:
// On CONTENT_ERROR:

5. kpi.totalRebufferingTime

Formula: Cumulative sum of rebuffering durations
kpi.totalRebufferingTime = Σ(rebuffer_duration_i) where buffer_type ≠ "initial"

Tracking Logic:
// On each CONTENT_BUFFER_END:

6. kpi.rebufferingRatio

Formula: Percentage of time spent rebuffering
double rebufferingRatio = ((double) qoeTotalRebufferingTime / totalPlaytime) * 100;

7. kpi.totalPlaytime

Formula: Direct attribute mapping
kpi.totalPlaytime = totalPlaytime

Source: Accumulated through updatePlaytime() mechanism

8. kpi.averageBitrate (NEW: Time-Weighted)

Formula: Time-weighted average of bitrates
// Primary calculation (time-weighted):
if (qoeTotalActiveTime > 0) {
kpi.averageBitrate = qoeTotalBitrateWeightedTime / qoeTotalActiveTime
}

// Fallback calculation (simple average):
else if (qoeBitrateCount > 0) {
kpi.averageBitrate = qoeBitrateSum / qoeBitrateCount
}

Time-Weighted Tracking:
// On each rendition change:
segmentDuration = currentTime - qoeLastRenditionChangeTime
qoeTotalBitrateWeightedTime += (previousBitrate × segmentDuration)
qoeTotalActiveTime += segmentDuration

// During calculation, include current segment:
currentSegmentDuration = currentTime - qoeLastRenditionChangeTime
totalWeightedTime = qoeTotalBitrateWeightedTime + (currentBitrate × currentSegmentDuration)
totalTime = qoeTotalActiveTime + currentSegmentDuration

averageBitrate = totalWeightedTime / totalTime

Mathematical Representation:
Average = Σ(bitrate_i × duration_i) / Σ(duration_i)

Where:

• bitrate_i = bitrate during segment i
• duration_i = time duration of segment i
• i = 1 to n rendition changes

[ametku]

I have added some comments as initial review. I need to verify more for qoe attrs.

[ametku]

The QOE_AGGREGATE data is has a lot more attrs. The attrs in QOE_AGGREGATE should be selected. Please check browser implementation for the same

[ametku]

@swatijha23 There is sometime wrong. these files should not be part of your PR. They are already part of master. can you fix it?

[ametku]

Even these files. I would suggest add your changes only part of this PR

[ametku]

This is actually not rendition change but bitrate change. Can you refer to browser implementation

[ametku]

why are we including timeSinceRequested for QOE ? Please check browser implementation to verify the attrs part of QOE event

[swatijha23]

#75