IegTools.FluentPollster 1.1.0-rc.1

IegTools.FluentPollster

FluentPollster provides a user-friendly fluent interface for creating easy-to-read polling tasks.
The library is written in C# 11.0 and targets .NET Standard 2.0 (.NET Core and .NET Framework).

Why another polling library?

I need polling for two scenarios

• get data from an third party Api
• get Temperatures from 1-Wire Bus DS18B20 sensors

I found that FluentScheduler didn't meet my requirements.
I had some ideas and well it's less than 500 loc at the moment, so that's nothing.
Hey and it's fun.

Usage

To get into the details, explore the Integration-Tests.

Simple polling job

You can add any Action as job to the PollsterBuilder,
specify the poll-interval and the condition,
build the Pollster and run it.

private IPollster _pollster;

public void SimplePolling()
{
    var counter = 0;
    var uut = PollsterBuilder.Create()
        .AddJob(() => counter++, TimeSpan.FromMilliseconds(100), () => HasWhatSoEverCondition());

    _pollster = uut.Build();
    
    // executes only once, so when and how you call it belongs to you
    _pollster.Execute();
}

Execute the pollster automatically every x minutes, seconds,...

You can add Actions also without any condition,
build the Pollster and run it in automatic-mode.

private IPollster _pollster;

public void AutomaticPolling()
{
    var counter = 0;
    var uut = PollsterBuilder.Create()
        .AddJob(() => counter++, TimeSpan.FromSeconds(5));

    _pollster = uut.Build();
    
    // run automatic (like FluentScheduler does it...)
    _pollster.RunAutomaticEvery(TimeSpan.FromSeconds(10));
}

Multiple interval polling job

You can add any Action with multiple interval/condition combinations as job to the PollsterBuilder,
build the Pollster and run it.

private IPollster _pollster;

public void MultipleIntervalPolling()
{
    var counter = 0;

    var intervals = new List<(TimeSpan, Func<bool>)>
    {
        (TimeSpan.FromSeconds(60),  () => Condition1()),
        (TimeSpan.FromSeconds(120), () => Condition2()),
    };

    var uut = PollsterBuilder.Create()
        .AddJob(() => counter++, intervals);

    var pollster = uut.Build();

    _pollster.Execute();
}

Additional settings

The FluentPollster needs no dependency injection but you can inject an ILogger so you will be informed about any exceptions thrown in your poll actions.
(all other important events are logged as 'Trace' at the moment)

And you can set the maximum number of poll tasks that should be executed during one poll cycle.

    _pollster = PollsterBuilder.Create()
        .SetLogger(logger)
        .SetMaxJobsPerPoll(10)
        .AddJob(() => Job1(), TimeSpan.FromSeconds(5));
        .AddJob(() => Job2(), TimeSpan.FromSeconds(10));
        .Build();

    _pollster.RunAutomaticEvery(TimeSpan.FromSeconds(1));

ExtensionMethods

At the moment there is only one ExtensionMethod, you can use
DateTime.Now.IsCurrentMinuteDivisibleBy(...) to force your polling task to run only at 'special' minutes within an hour.

Example:
Use DateTime.Now.IsCurrentMinuteDivisibleBy(5) as condition and your action will be called only in minute 0, 5, 10, 15 and so on
or:
Use DateTime.Now.IsCurrentMinuteDivisibleBy(15) as condition and your action will be called only in minute 0, 15, 30 and 45

for further information → IntegrationsTests...

    IsCurrentMinuteDivisibleBy(this DateTime time, int everyMinutes, int offsetMinute = 0)