Radarr/src/NzbDrone.Core/HealthCheck/Checks/DownloadClientCheck.cs

using System;
using System.Linq;
using NLog;
using NzbDrone.Core.Download;

namespace NzbDrone.Core.HealthCheck.Checks
{
    public class DownloadClientCheck : HealthCheckBase
    {
        private readonly IProvideDownloadClient _downloadClientProvider;
        private readonly Logger _logger;

        public DownloadClientCheck(IProvideDownloadClient downloadClientProvider, Logger logger)
        {
            _downloadClientProvider = downloadClientProvider;
            _logger = logger;
        }

        public override HealthCheck Check()
        {
            var downloadClients = _downloadClientProvider.GetDownloadClients().ToList();

            if (!downloadClients.Any())
            {
                return new HealthCheck(GetType(), HealthCheckResult.Warning, "No download client is available");
            }

            foreach (var downloadClient in downloadClients)
            {
                try
                {
                    downloadClient.GetItems();
                }
                catch (Exception ex)
                {
                    var message = String.Format("Unable to communicate with {0}.", downloadClient.Definition.Name);

                    _logger.ErrorException(message, ex);
                    return new HealthCheck(GetType(), HealthCheckResult.Error, message + " " + ex.Message);
                }
            }

            return new HealthCheck(GetType());
        }
    }
}