/// <inheritdoc/>
public static Protobuf.TimeSeriesPayload Append(this Protobuf.TimeSeriesPayload payload, IEnumerable <Protobuf.DataPoint> dataPoints)
{
payload = new Protobuf.TimeSeriesPayload(payload);
var originTimestamp = (payload.Timestep.Count > 0) ? payload.LastTimestamp : dataPoints.First().Timestamp;
var timeOffsets = dataPoints.Select(_ => _.Timestamp).TimestampToStepLength(originTimestamp).ToList();
payload.Timestep.AddRange(timeOffsets);
var values = dataPoints.Where(_ => _.MeasurementCase == Protobuf.DataPoint.MeasurementOneofCase.Value).Select(_ => _.Value);
var longitudes = dataPoints.Where(_ => _.MeasurementCase == Protobuf.DataPoint.MeasurementOneofCase.Coordinate).Select(_ => _.Coordinate.Longitude);
var latitudes = dataPoints.Where(_ => _.MeasurementCase == Protobuf.DataPoint.MeasurementOneofCase.Coordinate).Select(_ => _.Coordinate.Latitude);
if (payload.PayloadCase == Protobuf.TimeSeriesPayload.PayloadOneofCase.None)
{
switch (dataPoints.First().MeasurementCase)
{
case Protobuf.DataPoint.MeasurementOneofCase.Value:
payload.Values = new Protobuf.TimeSeriesPayload.Types.Values();
break;
case Protobuf.DataPoint.MeasurementOneofCase.Coordinate:
payload.Coordinates = new Protobuf.TimeSeriesPayload.Types.Coordinates();
break;
}
}
payload.Values?.Value?.AddRange(values);
payload.Coordinates?.Longitudes?.AddRange(longitudes);
payload.Coordinates?.Latitudes?.AddRange(latitudes);
payload.LastTimestamp = dataPoints.Last().Timestamp;
return(payload);
}
/// <summary>
///
/// </summary>
/// <param name="dataPoints"></param>
/// <returns></returns>
public static IEnumerable <byte> Compress(IEnumerable <DataPoint <dynamic> > dataPoints)
{
if (dataPoints.Select(_ => _.TimeSeries).Distinct().Count() > 1)
{
throw new Exception("Unable to compress data points: All data points must come from the same time series.");
}
var timeSeries = ByteString.CopyFrom(dataPoints.First().TimeSeries.Value.ToByteArray());
var firstTimestamp = dataPoints.First().Timestamp.Value;
var protobufDataPoints = dataPoints.Select(_ => _.ToProtobuf()).ToArray();
var frame = new Protobuf.TimeSeriesFrame {
TimeSeries = timeSeries, Timestamp = (ulong)firstTimestamp
};
var payload = new Protobuf.TimeSeriesPayload();
payload = payload.Append(protobufDataPoints);
frame.UncompressedPayload = payload;
frame = frame.Compress();
var encoded = frame.ToByteArray();
byte[] length = BitConverter.GetBytes((int)encoded.Length);
return(length.Concat(encoded));
}
