Merge pull request #562 from Artemis-RGB/feature/process-monitor

Core - Added Process Monitor Service

src/Artemis.Core/Services/ProcessMonitor/Events/ProcessEventArgs.cs

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+using System;
+using System.Diagnostics;
+
+namespace Artemis.Core.Services
+{
+    /// <summary>
+    /// Contains data for the ProcessMonitor process events
+    /// </summary>
+    public class ProcessEventArgs : EventArgs
+    {
+        /// <summary>
+        /// Gets the process related to the event
+        /// </summary>
+        public Process Process { get; }
+
+        internal ProcessEventArgs(Process process)
+        {
+            Process = process;
+        }
+    }
+}

src/Artemis.Core/Services/ProcessMonitor/Interfaces/IProcessMonitorService.cs

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+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Artemis.Core.Services
+{
+    /// <summary>
+    /// A service that provides events for started and stopped processes and a list of all running processes.
+    /// </summary>
+    public interface IProcessMonitorService : IArtemisService
+    {
+        /// <summary>
+        /// Occurs when a process starts.
+        /// </summary>
+        event EventHandler<ProcessEventArgs> ProcessStarted;
+
+        /// <summary>
+        /// Occurs when a process stops.
+        /// </summary>
+        event EventHandler<ProcessEventArgs> ProcessStopped;
+
+        /// <summary>
+        /// Returns an enumerable with the processes running on the system.
+        /// </summary>
+        IEnumerable<Process> GetRunningProcesses();
+    }
+}

src/Artemis.Core/Services/ProcessMonitor/ProcessMonitorService.cs

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+using Serilog;
+using System;
+using System.Collections.Generic;
+using System.Diagnostics;
+using System.Linq;
+using System.Timers;
+
+namespace Artemis.Core.Services
+{
+    internal class ProcessMonitorService : IProcessMonitorService
+    {
+        private readonly ILogger _logger;
+        private readonly Timer _processScanTimer;
+        private readonly ProcessComparer _comparer;
+        private Process[] _lastScannedProcesses;
+
+        public ProcessMonitorService(ILogger logger)
+        {
+            _logger = logger;
+            _lastScannedProcesses = Process.GetProcesses();
+            _processScanTimer = new Timer(1000);
+            _processScanTimer.Elapsed += OnTimerElapsed;
+            _processScanTimer.Start();
+            _comparer = new ProcessComparer();
+        }
+
+        public event EventHandler<ProcessEventArgs>? ProcessStarted;
+
+        public event EventHandler<ProcessEventArgs>? ProcessStopped;
+
+        public IEnumerable<Process> GetRunningProcesses()
+        {
+            return _lastScannedProcesses;
+        }
+
+        private void OnTimerElapsed(object sender, ElapsedEventArgs e)
+        {
+            Process[] newProcesses = Process.GetProcesses();
+            foreach (Process startedProcess in newProcesses.Except(_lastScannedProcesses, _comparer))
+            {
+                ProcessStarted?.Invoke(this, new ProcessEventArgs(startedProcess));
+                _logger.Debug("Started Process: {startedProcess}", startedProcess.ProcessName);
+            }
+
+            foreach (Process stoppedProcess in _lastScannedProcesses.Except(newProcesses, _comparer))
+            {
+                ProcessStopped?.Invoke(this, new ProcessEventArgs(stoppedProcess));
+                _logger.Debug("Stopped Process: {stoppedProcess}", stoppedProcess.ProcessName);
+            }
+
+            _lastScannedProcesses = newProcesses;
+        }
+    }
+
+    internal class ProcessComparer : IEqualityComparer<Process>
+    {
+        public bool Equals(Process? x, Process? y)
+        {
+            if (x == null && y == null) return true;
+            if (x == null || y == null) return false;
+            return x.Id == y.Id && x.ProcessName == y.ProcessName && x.SessionId == y.SessionId;
+        }
+
+        public int GetHashCode(Process obj)
+        {
+            if (obj == null) return 0;
+            return obj.Id;
+        }
+    }
+}