Converting a polling based API into a streaming API with the Reactive Extensions
Recently my building has been having issues with its boilers, and the heat has been going out for longer than is comfortable. The superintendent that makes a habit of periodically checking on the status of each of the boilers. A workable approach certainly, but figured this would be ideal for a technology assist.
For $9, I purchased a USB thermometer, word on the web is that the software comes with its fairly miserable (and crashed immediately on machine), but with some Google and reflector, was able to come up with a polling based API to read the temperature
public interface IUsbTEMPer
{
double Temperature { get; }
}
With the RX, converting the API into a stream of data is just one line:
IObservable<double> ts = Observable.Generate(
Scheduler.Later,
() => new Notification<double>.OnNext(usbTempReader.Temperature)
).Publish();
And getting some simple alerts is easy too:
ts.Buffer(new TimeSpan(1, 5, 0))
.Select(fiveminOfTemp => fiveminOfTemp.Average())
.Where(avgtemp => avgtemp < 65)
.Subscribe(cold => ToTwiter("buildingstatus account..."));