HostedServiceBase.cs

/// <summary>
/// Hosted service base class
/// </summary>
public abstract class HostedServiceBase : IHostedService, IDisposable
{
    private readonly TimeSpan dueTime;
    private readonly TimeSpan period;
    private Timer timer;

    /// <summary>
    /// Service provider
    /// </summary>
    protected IServiceProvider Services { get; }

    protected HostedServiceBase(IServiceProvider services, TimeSpan dueTime, TimeSpan period)
    {
        Services = services;
        this.dueTime = dueTime;
        this.period = period;
    }

    /// <summary>
    /// Background worker task
    /// </summary>
    protected abstract Task DoWork();

    /// <inheritdoc cref="IHostedService.StartAsync"/>
    public Task StartAsync(CancellationToken cancellationToken)
    {
        // RollbarLocator.RollbarInstance.Info($"{GetType().Name} started.");

        timer = new Timer(DoWork, null, dueTime, period);
        return Task.CompletedTask;
    }

    /// <summary>
    /// Timer update loop
    /// </summary>
    private async void DoWork(object state)
    {
        // RollbarLocator.RollbarInstance.Info($"{GetType().Name} DoWork.");

        try
        {
            await DoWork();
        }
        catch (Exception e)
        {
            RollbarLocator.RollbarInstance.Error(e);
        }
    }

    /// <inheritdoc cref="IHostedService.StopAsync"/>
    public Task StopAsync(CancellationToken cancellationToken)
    {
        // RollbarLocator.RollbarInstance.Info($"{GetType().Name} stopped.");

        timer?.Change(Timeout.Infinite, 0);
        return Task.CompletedTask;
    }

    /// <inheritdoc cref="IDisposable.Dispose" />
    public void Dispose()
    {
        timer?.Dispose();
    }
}