/// <summary>
/// Gets the history of a specific storage site and environmental factor.
/// </summary>
/// <param name="siteId">The ID of the storage site to get the history for.</param>
/// <param name="factor">The factor to get the history for.</param>
/// <param name="startTime">Start time of the period to get value for.</param>
/// <param name="endTime">End time of the period to get value for.</param>
/// <param name="maxPoints">Optional upper bound of points for data density reduction.</param>
/// <returns>Returns the matching values.</returns>
public IEnumerable <DataPoint> GetHistory(Guid siteId, EnvironmentalFactor factor, DateTime startTime, DateTime endTime, int?maxPoints)
{
StorageSite site = LocationsService.GetStorageSite(siteId);
IEnumerable <DataPoint> history = EnvironmentalDataRepository.GetHistory(site, factor, startTime, endTime);
if (maxPoints.HasValue && history.Count() > maxPoints)
{
history = DataDensityReducer.ReduceDensity(history, maxPoints.Value);
}
return(history);
}
/// <summary>
/// Sets up the service with all necessare components. Gets all known storage sites and starts data readers for each of them.
/// </summary>
/// <param name="loggerFactory">A factory to create loggers from.</param>
/// <param name="configuration">The app configuration.</param>
/// <param name="locationsService">Provides storage sites.</param>
/// <param name="environmentalDataRepository">Repository of environmental data.</param>
/// <param name="dataDensityReducer">Data density reducing strategy.</param>
public EnvironmentService(ILoggerFactory loggerFactory,
IConfiguration configuration,
LocationsService locationsService,
IEnvironmentalDataRepository environmentalDataRepository,
IDataDensityReducer dataDensityReducer)
{
LoggerFactory = loggerFactory;
Logger = LoggerFactory.CreateLogger <EnvironmentService>();
LocationsService = locationsService;
EnvironmentalDataRepository = environmentalDataRepository;
SnapshotQueue = new ConcurrentQueue <EnvironmentSnapshot>();
DataDensityReducer = dataDensityReducer;
// Get Kafka endpoint
KafkaEndpoint = configuration.GetValue("Kafka", "");
if (string.IsNullOrEmpty(KafkaEndpoint))
{
throw new Exception("Invalid Kafka endpoint provided!");
}
else
{
Logger.LogInformation($"Configured Kafka endpoint `{KafkaEndpoint}`.");
}
// Start reading from snapshot queue
QueueConsumer = new TaskFactory().StartNew(() =>
{
while (true)
{
if (SnapshotQueue.TryDequeue(out EnvironmentSnapshot snapshot))
{
EnvironmentalDataRepository.RecordEnvironmentalSnapshot(snapshot);
}
else
{
Task.Delay(1000);
}
}
});
// Set up data readers for all existing storage sites
DataReaders = new Dictionary <Guid, EnvironmentalDataReader>();
foreach (StorageSite site in LocationsService.GetAllStorageSites())
{
CreateAndRegisterDataReader(site);
}
// Subscribe to the creation of new storage sites
LocationsService.Subscribe(this);
// TODO: check for failed readers (Kafka not available?) and restart them
}
/// <summary>
/// Gets the min and max values for a specific storage site and environmental factor.
/// </summary>
/// <param name="siteId">The ID of the storage site to get the history for.</param>
/// <param name="factor">The factor to get the history for.</param>
/// <param name="startTime">Start time of the period to get value for.</param>
/// <param name="endTime">End time of the period to get value for.</param>
/// <returns>Returns the extrema.</returns>
public Extrema GetExtrema(Guid siteId, EnvironmentalFactor factor, DateTime startTime, DateTime endTime)
{
StorageSite site = LocationsService.GetStorageSite(siteId);
return(EnvironmentalDataRepository.GetExtrema(site, factor, startTime, endTime));
}
/// <summary>
/// Gets the latest value for a specific storage site and environmental factor.
/// </summary>
/// <param name="siteId">The ID of the storage site to get the latest value for.</param>
/// <param name="factor">The factor to get the latest value for.</param>
/// <returns>Returns the latest value, or null.</returns>
public DataPoint GetLatestValue(Guid siteId, EnvironmentalFactor factor)
{
StorageSite site = LocationsService.GetStorageSite(siteId);
return(EnvironmentalDataRepository.GetLatestValue(site, factor));
}