public IEnumerable <Reading> GetReadings(string stationId, DateTime date, LookBack lookBack = LookBack.Day)
{
var startDate = date.AddDays(-(int)lookBack);
using var con = new SQLiteConnection(@"URI=file:" + _configuration["DatabasePath"]);
con.Open();
using var cmd = new SQLiteCommand(con);
cmd.CommandText = "SELECT timestamp, temperature, humidity FROM dht_data WHERE station = @station AND timestamp >= @startTimestamp AND timestamp < @endTimestamp ORDER BY timestamp ASC LIMIT 30000;";
cmd.Parameters.AddWithValue("@station", stationId);
cmd.Parameters.AddWithValue("@startTimestamp", ((DateTimeOffset)startDate).ToUnixTimeSeconds());
cmd.Parameters.AddWithValue("@endTimestamp", ((DateTimeOffset)date).ToUnixTimeSeconds());
cmd.Prepare();
using SQLiteDataReader rdr = cmd.ExecuteReader();
while (rdr.Read())
{
yield return(new Reading
{
Timestamp = rdr.GetInt64(0),
Temperature = rdr.GetDouble(1),
Humidity = rdr.GetInt32(2),
});
}
con.Close();
}
private async Task CheckMeter(long size, CancellationToken cancellationToken)
{
if (BytesSent <= AverageBytesPerSecond)
{
DateTime meterTime = DateTime.Now.Subtract(LookBackWindow);
var current = LookBack.First;
while (!cancellationToken.IsCancellationRequested && current != null && current.Value.Time <= meterTime)
{
BytesSent -= current.Value.Value;
EventCount--;
current = current.Next;
LookBack.RemoveFirst();
}
}
LookBack.AddLast(new MeterItem <long>(size));
BytesSent += size;
EventCount++;
var time = (DateTime.UtcNow - LookBack.First.Value.Time).TotalMilliseconds;
if (BytesSent / time >= AverageBytesPerSecond)
{
await Backoff(cancellationToken);
}
}
public ActionResult Get(string stationId, string dateString, LookBack lookBack)
{
ViewBag.DateString = dateString;
ViewBag.StationId = stationId;
ViewBag.LookBack = lookBack;
return(View());
}
public Dictionary <string, double[][]> GetDay(string stationId, string dateString, LookBack lookBack)
{
var date = DateTime.ParseExact(dateString, "yyyy-MM-dd", CultureInfo.InvariantCulture);
var readings = GetReadings(stationId, date, lookBack).ToArray();
return(new Dictionary <string, double[][]>
{
{ "Temperature", readings.Select(x => new double[] { x.Timestamp * 1000, x.Temperature }).ToArray() },
{ "Humidity", readings.Select(x => new double[] { x.Timestamp * 1000, x.Humidity }).ToArray() },
});
}
