Moved all UnitTests to a single project. Implemented parts of AspNetCore UnitTests.

UnitTests/Common/Extensions/CryptographyHelperExtensionsTests.cs

@@ -0,0 +1,74 @@
+using System.Security.Cryptography;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class CryptographyHelperExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReturnMd5Hash()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = new byte[] { 0xaf, 0xfe };
+
+			// act
+			string strHash = str.Md5();
+			string byteHash = bytes.Md5();
+
+			// assert
+			Assert.AreEqual("ed076287532e86365e841e92bfc50d8c", strHash);
+			Assert.AreEqual("63c983de427ce9e2430ba8554d2a822f", byteHash);
+		}
+
+		[TestMethod]
+		public void ShouldReturnSha1Hash()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = new byte[] { 0xaf, 0xfe };
+
+			// act
+			string strHash = str.Sha1();
+			string byteHash = bytes.Sha1();
+
+			// assert
+			Assert.AreEqual("2ef7bde608ce5404e97d5f042f95f89f1c232871", strHash);
+			Assert.AreEqual("ec2c39d500316044fa49f6c8f471ddec8b4fb9d1", byteHash);
+		}
+
+		[TestMethod]
+		public void ShouldReturnSha256Hash()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = new byte[] { 0xaf, 0xfe };
+
+			// act
+			string strHash = str.Sha256();
+			string byteHash = bytes.Sha256();
+
+			// assert
+			Assert.AreEqual("7f83b1657ff1fc53b92dc18148a1d65dfc2d4b1fa3d677284addd200126d9069", strHash);
+			Assert.AreEqual("4e0da689dc7a51957be426d6cfb1bd860169cb25dd1ac946a2f141228217804a", byteHash);
+		}
+
+		[TestMethod]
+		public void ShouldReturnSha512Hash()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = new byte[] { 0xaf, 0xfe };
+
+			// act
+			string strHash = str.Sha512();
+			string byteHash = bytes.Sha512();
+
+			// assert
+			Assert.AreEqual("861844d6704e8573fec34d967e20bcfef3d424cf48be04e6dc08f2bd58c729743371015ead891cc3cf1c9d34b49264b510751b1ff9e537937bc46b5d6ff4ecc8", strHash);
+			Assert.AreEqual("591098c5d470a09f0ff48a4fdb7769ab89f803eae9e23b6f9f69dd228cca46c074bbc11a5fceaa8a5f48d14d2bf19a83a629266c2c5b7d9ef34623b64cb2f8e7", byteHash);
+		}
+	}
+}

UnitTests/Common/Extensions/DateTimeExtensionsTests.cs

@@ -0,0 +1,355 @@
+using System;
+using UnitTests.Common.Utils;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class DateTimeExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReturnUtc()
+		{
+			// arrange
+			var timeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById("Europe/Berlin");
+			using var _ = TimeZoneInfoLocalMock.Create(timeZoneInfo);
+
+			var utc = new DateTime(2021, 11, 15, 11, 22, 33, DateTimeKind.Utc);
+			var local = new DateTime(2021, 11, 15, 11, 22, 33, DateTimeKind.Local);
+			var unspecified = new DateTime(2021, 11, 15, 11, 22, 33, DateTimeKind.Unspecified);
+
+			// act
+			var utcCorrected = utc.AsUtc();
+			var localCorrected = local.AsUtc();
+			var unspecifiedCorrected = unspecified.AsUtc();
+
+			// assert
+			Assert.AreEqual(DateTimeKind.Utc, utcCorrected.Kind);
+			Assert.AreEqual(DateTimeKind.Utc, localCorrected.Kind);
+			Assert.AreEqual(DateTimeKind.Utc, unspecifiedCorrected.Kind);
+
+			Assert.AreEqual(utc, utcCorrected);
+			Assert.AreEqual(utc.AddHours(-1), localCorrected);
+			Assert.AreEqual(utc, unspecifiedCorrected);
+		}
+
+		[TestMethod]
+		public void ShouldReturnLocal()
+		{
+			// arrange
+			var timeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById("Europe/Berlin");
+			using var _ = TimeZoneInfoLocalMock.Create(timeZoneInfo);
+
+			var utc = new DateTime(2021, 11, 15, 11, 22, 33, DateTimeKind.Utc);
+			var local = new DateTime(2021, 11, 15, 11, 22, 33, DateTimeKind.Local);
+			var unspecified = new DateTime(2021, 11, 15, 11, 22, 33, DateTimeKind.Unspecified);
+
+			// act
+			var utcCorrected = utc.AsLocal();
+			var localCorrected = local.AsLocal();
+			var unspecifiedCorrected = unspecified.AsLocal();
+
+			// assert
+			Assert.AreEqual(DateTimeKind.Local, utcCorrected.Kind);
+			Assert.AreEqual(DateTimeKind.Local, localCorrected.Kind);
+			Assert.AreEqual(DateTimeKind.Local, unspecifiedCorrected.Kind);
+
+			Assert.AreEqual(local.AddHours(1), utcCorrected);
+			Assert.AreEqual(local, localCorrected);
+			Assert.AreEqual(local, unspecifiedCorrected);
+		}
+
+		[TestMethod]
+		public void ShouldReturnCorrectUtcAlignmentDaylightSavingEnd()
+		{
+			// arrange
+			var dateTime = new DateTime(2021, 10, 30, 12, 15, 30, 45, DateTimeKind.Utc);
+
+			var intervalThreeSeconds = TimeSpan.FromSeconds(3);
+			var intervalSixMinutes = TimeSpan.FromMinutes(6);
+			var intervalTwoHours = TimeSpan.FromHours(2);
+			var intervalDay = TimeSpan.FromDays(1);
+
+			var offsetTwoMinutes = TimeSpan.FromMinutes(2);
+			var offsetFourHours = TimeSpan.FromHours(4);
+
+			// act
+			var diffThreeSeconds = intervalThreeSeconds.GetAlignedInterval(dateTime);
+			var diffSixMinutes = intervalSixMinutes.GetAlignedInterval(dateTime);
+			var diffTwoHours = intervalTwoHours.GetAlignedInterval(dateTime);
+			var diffDay = intervalDay.GetAlignedInterval(dateTime);
+
+			var diffTwoHoursOffset = intervalTwoHours.GetAlignedInterval(dateTime, offsetTwoMinutes);
+			var diffDayOffset = intervalDay.GetAlignedInterval(dateTime, offsetFourHours);
+
+			// assert
+			Assert.AreEqual(TimeSpan.Parse("00:00:02.955"), diffThreeSeconds);
+			Assert.AreEqual(TimeSpan.Parse("00:02:29.955"), diffSixMinutes);
+			Assert.AreEqual(TimeSpan.Parse("01:44:29.955"), diffTwoHours);
+			Assert.AreEqual(TimeSpan.Parse("11:44:29.955"), diffDay);
+
+			Assert.AreEqual(TimeSpan.Parse("01:46:29.955"), diffTwoHoursOffset);
+			Assert.AreEqual(TimeSpan.Parse("15:44:29.955"), diffDayOffset);   // must be the same whether daylight saving has ended
+		}
+
+		[TestMethod]
+		public void ShouldReturnCorrectUtcAlignmentDaylightSavingStart()
+		{
+			// arrange
+			var dateTime = new DateTime(2022, 3, 26, 12, 15, 30, 45, DateTimeKind.Utc);
+
+			var intervalThreeSeconds = TimeSpan.FromSeconds(3);
+			var intervalSixMinutes = TimeSpan.FromMinutes(6);
+			var intervalTwoHours = TimeSpan.FromHours(2);
+			var intervalDay = TimeSpan.FromDays(1);
+
+			var offsetTwoMinutes = TimeSpan.FromMinutes(2);
+			var offsetFourHours = TimeSpan.FromHours(4);
+
+			// act
+			var diffThreeSeconds = intervalThreeSeconds.GetAlignedInterval(dateTime);
+			var diffSixMinutes = intervalSixMinutes.GetAlignedInterval(dateTime);
+			var diffTwoHours = intervalTwoHours.GetAlignedInterval(dateTime);
+			var diffDay = intervalDay.GetAlignedInterval(dateTime);
+
+			var diffTwoHoursOffset = intervalTwoHours.GetAlignedInterval(dateTime, offsetTwoMinutes);
+			var diffDayOffset = intervalDay.GetAlignedInterval(dateTime, offsetFourHours);
+
+			// assert
+			Assert.AreEqual(TimeSpan.Parse("00:00:02.955"), diffThreeSeconds);
+			Assert.AreEqual(TimeSpan.Parse("00:02:29.955"), diffSixMinutes);
+			Assert.AreEqual(TimeSpan.Parse("01:44:29.955"), diffTwoHours);
+			Assert.AreEqual(TimeSpan.Parse("11:44:29.955"), diffDay);
+
+			Assert.AreEqual(TimeSpan.Parse("01:46:29.955"), diffTwoHoursOffset);
+			Assert.AreEqual(TimeSpan.Parse("15:44:29.955"), diffDayOffset);   // must be the same whether daylight saving has started
+		}
+
+		[TestMethod]
+		public void ShouldReturnCorrectLocalAlignmentDaylightSavingEnd()
+		{
+			// arrange
+			var timeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById("Europe/Berlin");
+			using var _ = TimeZoneInfoLocalMock.Create(timeZoneInfo);
+
+			var dateTime = new DateTime(2021, 10, 30, 12, 15, 30, 45, DateTimeKind.Local);
+
+			var intervalThreeSeconds = TimeSpan.FromSeconds(3);
+			var intervalSixMinutes = TimeSpan.FromMinutes(6);
+			var intervalTwoHours = TimeSpan.FromHours(2);
+			var intervalDay = TimeSpan.FromDays(1);
+
+			var offsetTwoMinutes = TimeSpan.FromMinutes(2);
+			var offsetFourHours = TimeSpan.FromHours(4);
+
+			// act
+			var diffThreeSeconds = intervalThreeSeconds.GetAlignedInterval(dateTime);
+			var diffSixMinutes = intervalSixMinutes.GetAlignedInterval(dateTime);
+			var diffTwoHours = intervalTwoHours.GetAlignedInterval(dateTime);
+			var diffDay = intervalDay.GetAlignedInterval(dateTime);
+
+			var diffTwoHoursOffset = intervalTwoHours.GetAlignedInterval(dateTime, offsetTwoMinutes);
+			var diffDayOffset = intervalDay.GetAlignedInterval(dateTime, offsetFourHours);
+
+			// assert
+			Assert.AreEqual(TimeSpan.Parse("00:00:02.955"), diffThreeSeconds);
+			Assert.AreEqual(TimeSpan.Parse("00:02:29.955"), diffSixMinutes);
+			Assert.AreEqual(TimeSpan.Parse("01:44:29.955"), diffTwoHours);
+			Assert.AreEqual(TimeSpan.Parse("11:44:29.955"), diffDay);
+
+			Assert.AreEqual(TimeSpan.Parse("01:46:29.955"), diffTwoHoursOffset);
+			Assert.AreEqual(TimeSpan.Parse("14:44:29.955"), diffDayOffset);   // has to be minus one hour due to daylight saving ended
+		}
+
+		[TestMethod]
+		public void ShouldReturnCorrectLocalAlignmentDaylightSavingStart()
+		{
+			// arrange
+			var timeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById("Europe/Berlin");
+			using var _ = TimeZoneInfoLocalMock.Create(timeZoneInfo);
+
+			var dateTime = new DateTime(2022, 3, 26, 12, 15, 30, 45, DateTimeKind.Local);
+
+			var intervalThreeSeconds = TimeSpan.FromSeconds(3);
+			var intervalSixMinutes = TimeSpan.FromMinutes(6);
+			var intervalTwoHours = TimeSpan.FromHours(2);
+			var intervalDay = TimeSpan.FromDays(1);
+
+			var offsetTwoMinutes = TimeSpan.FromMinutes(2);
+			var offsetFourHours = TimeSpan.FromHours(4);
+
+			// act
+			var diffThreeSeconds = intervalThreeSeconds.GetAlignedInterval(dateTime);
+			var diffSixMinutes = intervalSixMinutes.GetAlignedInterval(dateTime);
+			var diffTwoHours = intervalTwoHours.GetAlignedInterval(dateTime);
+			var diffDay = intervalDay.GetAlignedInterval(dateTime);
+
+			var diffTwoHoursOffset = intervalTwoHours.GetAlignedInterval(dateTime, offsetTwoMinutes);
+			var diffDayOffset = intervalDay.GetAlignedInterval(dateTime, offsetFourHours);
+
+			// assert
+			Assert.AreEqual(TimeSpan.Parse("00:00:02.955"), diffThreeSeconds);
+			Assert.AreEqual(TimeSpan.Parse("00:02:29.955"), diffSixMinutes);
+			Assert.AreEqual(TimeSpan.Parse("01:44:29.955"), diffTwoHours);
+			Assert.AreEqual(TimeSpan.Parse("11:44:29.955"), diffDay);
+
+			Assert.AreEqual(TimeSpan.Parse("01:46:29.955"), diffTwoHoursOffset);
+			Assert.AreEqual(TimeSpan.Parse("16:44:29.955"), diffDayOffset);   // has to be plus one hour due to daylight saving started
+		}
+
+		[TestMethod]
+		public void ShouldReturnCorrectAlignment()
+		{
+			// arrange
+			var timeZoneInfo = TimeZoneInfo.FindSystemTimeZoneById("Europe/Berlin");
+			using var _ = TimeZoneInfoLocalMock.Create(timeZoneInfo);
+
+			var interval = TimeSpan.FromDays(1);
+
+			// act
+			var intervalUtc = interval.GetAlignedIntervalUtc();
+			var intervalLocal = interval.GetAlignedIntervalLocal();
+
+			// assert
+			Assert.AreEqual(DateTime.UtcNow.TimeOfDay.RoundToSecond(), (interval - intervalUtc).RoundToSecond());
+			Assert.AreEqual(DateTime.Now.TimeOfDay.RoundToSecond(), (interval - intervalLocal).RoundToSecond());
+
+			Assert.AreEqual((DateTime.Now - DateTime.UtcNow).RoundToSecond(), (intervalUtc - intervalLocal).RoundToSecond());
+		}
+
+		[TestMethod]
+		public void ShouldReturnCorrectShortStringForTimeSpan()
+		{
+			// arrange
+			var timeSpan = TimeSpan.Parse("1.10:11:12.345");
+			var negativeTimeSpan = TimeSpan.FromDays(-1.234);
+
+			// act
+			string shortString = timeSpan.ToShortString(withMilliseconds: false);
+			string shortStringWithMillis = timeSpan.ToShortString(withMilliseconds: true);
+			string shortStringNegative = negativeTimeSpan.ToShortString(withMilliseconds: true);
+
+			// assert
+			Assert.AreEqual("1d 10h 11m 12s", shortString);
+			Assert.AreEqual("1d 10h 11m 12s 345ms", shortStringWithMillis);
+			Assert.AreEqual("-1d 5h 36m 57s 600ms", shortStringNegative);
+		}
+
+		[TestMethod]
+		public void ShouldRoundToSecond()
+		{
+			// arrange
+			var timestampUp = new DateTime(2021, 11, 16, 20, 15, 30, 500);
+			var timestampDown = new DateTime(2021, 11, 16, 20, 15, 30, 499);
+
+			var timespanUp = new TimeSpan(1, 2, 3, 4, 500);
+			var timespanDown = new TimeSpan(1, 2, 3, 4, 499);
+
+			// act
+			var timestampUpRounded = timestampUp.RoundToSecond();
+			var timestampDownRounded = timestampDown.RoundToSecond();
+
+			var timespanUpRounded = timespanUp.RoundToSecond();
+			var timespanDownRounded = timespanDown.RoundToSecond();
+
+			// assert
+			Assert.AreNotEqual(timestampUp, timestampUpRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-16 20:15:31.000"), timestampUpRounded);
+			Assert.AreNotEqual(timestampDown, timestampDownRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-16 20:15:30.000"), timestampDownRounded);
+
+			Assert.AreNotEqual(timespanUp, timespanUpRounded);
+			Assert.AreEqual(TimeSpan.Parse("1.02:03:05.000"), timespanUpRounded);
+			Assert.AreNotEqual(timespanDown, timespanDownRounded);
+			Assert.AreEqual(TimeSpan.Parse("1.02:03:04.000"), timespanDownRounded);
+		}
+
+		[TestMethod]
+		public void ShouldRoundToMinute()
+		{
+			// arrange
+			var timestampUp = new DateTime(2021, 11, 16, 20, 15, 30, 0);
+			var timestampDown = new DateTime(2021, 11, 16, 20, 15, 29, 999);
+
+			var timespanUp = new TimeSpan(1, 2, 3, 30, 0);
+			var timespanDown = new TimeSpan(1, 2, 3, 29, 999);
+
+			// act
+			var timestampUpRounded = timestampUp.RoundToMinute();
+			var timestampDownRounded = timestampDown.RoundToMinute();
+
+			var timespanUpRounded = timespanUp.RoundToMinute();
+			var timespanDownRounded = timespanDown.RoundToMinute();
+
+			// assert
+			Assert.AreNotEqual(timestampUp, timestampUpRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-16 20:16:00.000"), timestampUpRounded);
+			Assert.AreNotEqual(timestampDown, timestampDownRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-16 20:15:00.000"), timestampDownRounded);
+
+			Assert.AreNotEqual(timespanUp, timespanUpRounded);
+			Assert.AreEqual(TimeSpan.Parse("1.02:04:00.000"), timespanUpRounded);
+			Assert.AreNotEqual(timespanDown, timespanDownRounded);
+			Assert.AreEqual(TimeSpan.Parse("1.02:03:00.000"), timespanDownRounded);
+		}
+
+		[TestMethod]
+		public void ShouldRoundToHour()
+		{
+			// arrange
+			var timestampUp = new DateTime(2021, 11, 16, 20, 30, 0, 0);
+			var timestampDown = new DateTime(2021, 11, 16, 20, 29, 59, 999);
+
+			var timespanUp = new TimeSpan(1, 2, 30, 0, 0);
+			var timespanDown = new TimeSpan(1, 2, 29, 59, 999);
+
+			// act
+			var timestampUpRounded = timestampUp.RoundToHour();
+			var timestampDownRounded = timestampDown.RoundToHour();
+
+			var timespanUpRounded = timespanUp.RoundToHour();
+			var timespanDownRounded = timespanDown.RoundToHour();
+
+			// assert
+			Assert.AreNotEqual(timestampUp, timestampUpRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-16 21:00:00.000"), timestampUpRounded);
+			Assert.AreNotEqual(timestampDown, timestampDownRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-16 20:00:00.000"), timestampDownRounded);
+
+			Assert.AreNotEqual(timespanUp, timespanUpRounded);
+			Assert.AreEqual(TimeSpan.Parse("1.03:00:00.000"), timespanUpRounded);
+			Assert.AreNotEqual(timespanDown, timespanDownRounded);
+			Assert.AreEqual(TimeSpan.Parse("1.02:00:00.000"), timespanDownRounded);
+		}
+
+		[TestMethod]
+		public void ShouldRoundToDay()
+		{
+			// arrange
+			var timestampUp = new DateTime(2021, 11, 16, 12, 0, 0, 0);
+			var timestampDown = new DateTime(2021, 11, 16, 11, 59, 59, 999);
+
+			var timespanUp = new TimeSpan(1, 12, 0, 0, 0);
+			var timespanDown = new TimeSpan(1, 11, 59, 59, 999);
+
+			// act
+			var timestampUpRounded = timestampUp.RoundToDay();
+			var timestampDownRounded = timestampDown.RoundToDay();
+
+			var timespanUpRounded = timespanUp.RoundToDay();
+			var timespanDownRounded = timespanDown.RoundToDay();
+
+			// assert
+			Assert.AreNotEqual(timestampUp, timestampUpRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-17 00:00:00.000"), timestampUpRounded);
+			Assert.AreNotEqual(timestampDown, timestampDownRounded);
+			Assert.AreEqual(DateTime.Parse("2021-11-16 00:00:00.000"), timestampDownRounded);
+
+			Assert.AreNotEqual(timespanUp, timespanUpRounded);
+			Assert.AreEqual(TimeSpan.Parse("2.00:00:00.000"), timespanUpRounded);
+			Assert.AreNotEqual(timespanDown, timespanDownRounded);
+			Assert.AreEqual(TimeSpan.Parse("1.00:00:00.000"), timespanDownRounded);
+		}
+	}
+}

UnitTests/Common/Extensions/EnumExtensionsTests.cs

@@ -0,0 +1,121 @@
+using System;
+using System.Linq;
+using UnitTests.Common.Utils;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using DescriptionAttribute = System.ComponentModel.DescriptionAttribute;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class EnumExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReturnEmptyList()
+		{
+			// arrange
+			var enumValue = TestEnum.Two;
+
+			// act
+			var customList = enumValue.GetAttributes<CustomMultipleAttribute>();
+			var descriptionList = enumValue.GetAttributes<DescriptionAttribute>();
+
+			// assert
+			Assert.IsNotNull(customList);
+			Assert.IsFalse(customList.Any());
+			Assert.IsNotNull(descriptionList);
+			Assert.IsFalse(descriptionList.Any());
+		}
+
+		[TestMethod]
+		public void ShouldReturnList()
+		{
+			// arrange
+			var enumValue = TestEnum.Zero;
+
+			// act
+			var customList = enumValue.GetAttributes<CustomMultipleAttribute>();
+			var descriptionList = enumValue.GetAttributes<DescriptionAttribute>();
+
+			// assert
+			Assert.IsNotNull(customList);
+			Assert.IsTrue(customList.Any());
+			Assert.AreEqual(2, customList.Count());
+			Assert.IsNotNull(descriptionList);
+			Assert.IsTrue(descriptionList.Any());
+			Assert.AreEqual(1, descriptionList.Count());
+		}
+
+		[TestMethod]
+		public void ShouldReturnNothing()
+		{
+			// arrange
+			var enumValue = TestEnum.Two;
+
+			// act
+			var customAttribute = enumValue.GetAttribute<CustomMultipleAttribute>();
+			var descriptionAttribute = enumValue.GetAttribute<DescriptionAttribute>();
+
+			// assert
+			Assert.IsNull(customAttribute);
+			Assert.IsNull(descriptionAttribute);
+		}
+
+		[TestMethod]
+		public void ShouldReturnFirstAttribute()
+		{
+			// arrange
+			var enumValue = TestEnum.Zero;
+
+			// act
+			var customAttribute = enumValue.GetAttribute<CustomMultipleAttribute>();
+			var descriptionAttribute = enumValue.GetAttribute<DescriptionAttribute>();
+
+			// assert
+			Assert.IsNotNull(customAttribute);
+			Assert.AreEqual("nix", customAttribute.Name);
+			Assert.IsNotNull(descriptionAttribute);
+			Assert.AreEqual("Null", descriptionAttribute.Description);
+		}
+
+		[TestMethod]
+		public void ShouldReturnDescriptionOrStringRepresentation()
+		{
+			// arrange
+			var enumWithDescription = TestEnum.One;
+			var enumWithoutDescripton = TestEnum.Two;
+
+			// act
+			string description = enumWithDescription.GetDescription();
+			string noDescription = enumWithoutDescripton.GetDescription();
+
+			// assert
+			Assert.AreEqual("Eins", description);
+			Assert.AreEqual(enumWithoutDescripton.ToString(), noDescription);
+		}
+
+		[TestMethod]
+		public void ShouldReturnEmptyListOnNotDefinedEnumValue()
+		{
+			// arrange
+			var notDefinedEnum = (TestEnum)10;
+
+			// act
+			var list = notDefinedEnum.GetAttributes<DescriptionAttribute>();
+
+			// assert
+			Assert.IsFalse(list.Any());
+		}
+
+		internal enum TestEnum
+		{
+			[CustomMultiple("nix")]
+			[CustomMultiple("Null")]
+			[Description("Null")]
+			Zero,
+			[Description("Eins")]
+			One,
+			Two,
+		}
+	}
+}

UnitTests/Common/Extensions/ExceptionExtensionsTests.cs

@@ -0,0 +1,75 @@
+using System;
+using System.Collections.Generic;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class ExceptionExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReturnExceptionMessage()
+		{
+			// arrange
+			var exception = new Exception("This is a message.");
+
+			// act
+			string message = exception.GetMessage();
+
+			// assert
+			Assert.AreEqual(exception.Message, message);
+		}
+
+		[TestMethod]
+		public void ShouldReturnInnerExceptionMessage()
+		{
+			// arrange
+			var innerException = new Exception("Message from the inner side.");
+			var outerException = new Exception("Message from the outer side.", innerException);
+
+			// act
+			string message = outerException.GetMessage();
+
+			// assert
+			Assert.AreEqual(innerException.Message, message);
+		}
+
+		[TestMethod]
+		public void ShouldReturnRecursiveExceptionMessageFoInnerException()
+		{
+			// arrange
+			var innerException = new Exception("Message from the inner side.");
+			var outerException = new Exception("Message from the outer side. See the inner exception for details.", innerException);
+			string expectedMessage = $"Message from the outer side. Message from the inner side.";
+
+			// act
+			string message = outerException.GetRecursiveMessage();
+
+			// assert
+			Assert.AreEqual(expectedMessage, message);
+		}
+
+		[TestMethod]
+		public void ShouldReturnRecursiveExceptionMessageFoInnerExceptions()
+		{
+			// arrange
+			var innerExceptions = new List<Exception>
+			{
+				new Exception("Inner Exception 1."),
+				new Exception("Inner Exception 2. See the inner exception for details.", new Exception("Inner Exception of Exception 2.")),
+				new Exception("Inner Exception 3."),
+				new Exception("Inner Exception 4."),
+				new Exception("Inner Exception 5.")
+			};
+			var aggregateException = new AggregateException("Lots of exceptions.", innerExceptions);
+			string expectedMessage = "Inner Exception 1. Inner Exception 2. Inner Exception of Exception 2. Inner Exception 3.";
+
+			// act
+			string message = aggregateException.GetRecursiveMessage();
+
+			// assert
+			Assert.AreEqual(expectedMessage, message);
+		}
+	}
+}

UnitTests/Common/Extensions/JsonExtensionsTests.cs

@@ -0,0 +1,341 @@
+using System;
+using System.Collections;
+using UnitTests.Common.Utils;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class JsonExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReturnJson()
+		{
+			// arrange
+			var testObject = new JsonTestClass();
+			string expected = @"{""stringValue"":""Hello World!"",""isBoolTrue"":true,""floatValue"":12.34,""doubleValue"":21.42,""decimalValue"":42.21,""localTimestamp"":""2021-11-16T20:15:34+01:00"",""utcTimestamp"":""2021-11-16T20:15:34Z"",""object"":{""integerValue"":42,""stringValue"":""Foo-Bar""}}";
+
+			// act
+			string json = testObject.SerializeJson();
+
+			// assert
+			Assert.IsFalse(string.IsNullOrWhiteSpace(json));
+			Assert.AreEqual(expected, json);
+		}
+
+		[TestMethod]
+		public void ShouldReturnJsonIndented()
+		{
+			// arrange
+			var testObject = new JsonTestClass();
+			string expected = @"{
+  ""stringValue"": ""Hello World!"",
+  ""isBoolTrue"": true,
+  ""floatValue"": 12.34,
+  ""doubleValue"": 21.42,
+  ""decimalValue"": 42.21,
+  ""localTimestamp"": ""2021-11-16T20:15:34+01:00"",
+  ""utcTimestamp"": ""2021-11-16T20:15:34Z"",
+  ""object"": {
+    ""integerValue"": 42,
+    ""stringValue"": ""Foo-Bar""
+  }
+}";
+
+			// act
+			string json = testObject.SerializeJson(indented: true);
+
+			// assert
+			Assert.IsFalse(string.IsNullOrWhiteSpace(json));
+			Assert.AreEqual(expected.Replace("\r", ""), json.Replace("\r", ""));
+		}
+
+		[TestMethod]
+		public void ShouldReturnJsonWithSingleQuotes()
+		{
+			// arrange
+			var testObject = new JsonTestClass
+			{
+				StringValue = "Sam's Pub"
+			};
+			string expected = "{'stringValue':'Sam\\'s Pub','isBoolTrue':true,'floatValue':12.34,'doubleValue':21.42,'decimalValue':42.21,'localTimestamp':'2021-11-16T20:15:34+01:00','utcTimestamp':'2021-11-16T20:15:34Z','object':{'integerValue':42,'stringValue':'Foo-Bar'}}";
+
+			// act
+			string json = testObject.SerializeJson(useSingleQuotes: true);
+
+			// assert
+			Assert.IsFalse(string.IsNullOrWhiteSpace(json));
+			Assert.AreEqual(expected, json);
+		}
+
+		[TestMethod]
+		public void ShouldReturnJsonWithoutCamelCase()
+		{
+			// arrange
+			var testObject = new JsonTestClass();
+			string expected = @"{""StringValue"":""Hello World!"",""IsBoolTrue"":true,""FloatValue"":12.34,""DoubleValue"":21.42,""DecimalValue"":42.21,""LocalTimestamp"":""2021-11-16T20:15:34+01:00"",""UtcTimestamp"":""2021-11-16T20:15:34Z"",""Object"":{""IntegerValue"":42,""StringValue"":""Foo-Bar""}}";
+
+			// act
+			string json = testObject.SerializeJson(useCamelCase: false);
+
+			// assert
+			Assert.IsFalse(string.IsNullOrWhiteSpace(json));
+			Assert.AreEqual(expected, json);
+		}
+
+		[TestMethod]
+		public void ShouldReturnJsonWithType()
+		{
+			// arrange
+			var testObject = new JsonTestClass();
+			string expected = @"{""$type"":""UnitTests.Common.Utils.JsonTestClass, UnitTests"",""stringValue"":""Hello World!"",""isBoolTrue"":true,""floatValue"":12.34,""doubleValue"":21.42,""decimalValue"":42.21,""localTimestamp"":""2021-11-16T20:15:34+01:00"",""utcTimestamp"":""2021-11-16T20:15:34Z"",""object"":{""$type"":""UnitTests.Common.Utils.JsonTestSubClass, UnitTests"",""integerValue"":42,""stringValue"":""Foo-Bar""}}";
+
+			// act
+			string json = testObject.SerializeJson(includeType: true);
+
+			// assert
+			Assert.IsFalse(string.IsNullOrWhiteSpace(json));
+			Assert.AreEqual(expected, json);
+		}
+
+		[TestMethod]
+		public void ShouldDeserializeWithoutFallback()
+		{
+			// arrange
+			string workingJson = @"{""stringValue"":""Some fancy string"",""isBoolTrue"":false,""floatValue"":12.34,""doubleValue"":21.42,""decimalValue"":123.45,""localTimestamp"":""2021-11-15T20:15:34+01:00"",""utcTimestamp"":""2021-10-16T20:15:34Z"",""object"":{""integerValue"":21,""stringValue"":""FooBar""}}";
+			string brokenJson = @"{""strValue"":""Some fancy string"",""isBoolTrue"":false,""floatValue"":12.34,""doubleValue"":21.42,""decimalValue"":123.45,""localTimestamp"":""2021-11-15T20:15:34+01:00"",""utcTimestamp"":""2021-10-16T20:15:34Z"",""object"":{""integerValue"":21.12,""stringValue"":""FooBar""}}";
+			string emptyString = "";
+
+			// act
+			var workingObj = workingJson.DeserializeJson<JsonTestClass>();
+			var emptyObj = emptyString.DeserializeJson<JsonTestClass>();
+
+			try
+			{
+				var brokenObj = brokenJson.DeserializeJson<JsonTestClass>();
+				Assert.Fail();
+			}
+			catch (JsonReaderException)
+			{ }
+
+			// assert
+			Assert.IsNotNull(workingObj);
+			Assert.IsNull(emptyObj);
+
+			Assert.AreEqual("Some fancy string", workingObj.StringValue);
+			Assert.IsFalse(workingObj.IsBoolTrue);
+			Assert.AreEqual(123.45m, workingObj.DecimalValue);
+			Assert.AreEqual(DateTimeKind.Local, workingObj.LocalTimestamp.Kind);
+			Assert.AreEqual("15.11.2021 20:15:34", workingObj.LocalTimestamp.ToString("dd.MM.yyyy HH:mm:ss"));
+			Assert.AreEqual(DateTimeKind.Utc, workingObj.UtcTimestamp.Kind);
+			Assert.AreEqual("16.10.2021 20:15:34", workingObj.UtcTimestamp.ToString("dd.MM.yyyy HH:mm:ss"));
+		}
+
+		[TestMethod]
+		public void ShouldDeserializeWithFallback()
+		{
+			// arrange
+			string workingJson = @"{""stringValue"":""Some fancy string"",""isBoolTrue"":false,""floatValue"":12.34,""doubleValue"":21.42,""decimalValue"":123.45,""localTimestamp"":""2021-11-15T20:15:34+01:00"",""utcTimestamp"":""2021-10-16T20:15:34Z"",""object"":{""integerValue"":21,""stringValue"":""FooBar""}}";
+			string brokenJson = @"{""strValue"":""Some fancy string"",""isBoolTrue"":false,""floatValue"":12.34,""doubleValue"":21.42,""decimalValue"":123.45,""localTimestamp"":""2021-11-15T20:15:34+01:00"",""utcTimestamp"":""2021-10-16T20:15:34Z"",""object"":{""integerValue"":21.12,""stringValue"":""FooBar""}}";
+			string emptyString = "";
+			var fallback = new JsonTestClass
+			{
+				DoubleValue = 0.815
+			};
+
+			// act
+			var workingObj = workingJson.DeserializeJson(fallback);
+			var brokenObj = brokenJson.DeserializeJson(fallback);
+			var emptyObj = emptyString.DeserializeJson(fallback);
+
+			// assert
+			Assert.IsNotNull(workingObj);
+			Assert.IsNotNull(brokenObj);
+			Assert.IsNull(emptyObj);
+
+			Assert.AreEqual("Some fancy string", workingObj.StringValue);
+			Assert.IsFalse(workingObj.IsBoolTrue);
+			Assert.AreEqual(123.45m, workingObj.DecimalValue);
+			Assert.AreEqual(21.42, workingObj.DoubleValue);
+			Assert.AreEqual(DateTimeKind.Local, workingObj.LocalTimestamp.Kind);
+			Assert.AreEqual("15.11.2021 20:15:34", workingObj.LocalTimestamp.ToString("dd.MM.yyyy HH:mm:ss"));
+			Assert.AreEqual(DateTimeKind.Utc, workingObj.UtcTimestamp.Kind);
+			Assert.AreEqual("16.10.2021 20:15:34", workingObj.UtcTimestamp.ToString("dd.MM.yyyy HH:mm:ss"));
+
+			Assert.AreEqual(fallback.StringValue, brokenObj.StringValue);
+			Assert.AreEqual(fallback.IsBoolTrue, brokenObj.IsBoolTrue);
+			Assert.AreEqual(fallback.DecimalValue, brokenObj.DecimalValue);
+			Assert.AreEqual(fallback.DoubleValue, brokenObj.DoubleValue);
+			Assert.AreEqual(fallback.LocalTimestamp.Kind, brokenObj.LocalTimestamp.Kind);
+			Assert.AreEqual(fallback.LocalTimestamp, brokenObj.LocalTimestamp);
+			Assert.AreEqual(fallback.UtcTimestamp.Kind, brokenObj.UtcTimestamp.Kind);
+			Assert.AreEqual(fallback.UtcTimestamp, brokenObj.UtcTimestamp);
+		}
+
+		[TestMethod]
+		public void ShouldDeserializeUsingPopulate()
+		{
+			// arrange
+			string json = @"{""stringValue"":""Some fancy string"",""isBoolTrue"":false,""floatValue"":12.34,""doubleValue"":21.42,""decimalValue"":123.45,""localTimestamp"":""2021-11-15T20:15:34+01:00"",""utcTimestamp"":""2021-10-16T20:15:34Z"",""object"":{""integerValue"":21,""stringValue"":""FooBar""}}";
+			var obj = new JsonTestClass();
+
+			// act
+			obj.DeserializeJson(json);
+
+			// assert
+			Assert.AreEqual("Some fancy string", obj.StringValue);
+			Assert.IsFalse(obj.IsBoolTrue);
+			Assert.AreEqual(123.45m, obj.DecimalValue);
+			Assert.AreEqual(21.42, obj.DoubleValue);
+			Assert.AreEqual(DateTimeKind.Local, obj.LocalTimestamp.Kind);
+			Assert.AreEqual("15.11.2021 20:15:34", obj.LocalTimestamp.ToString("dd.MM.yyyy HH:mm:ss"));
+			Assert.AreEqual(DateTimeKind.Utc, obj.UtcTimestamp.Kind);
+			Assert.AreEqual("16.10.2021 20:15:34", obj.UtcTimestamp.ToString("dd.MM.yyyy HH:mm:ss"));
+		}
+
+		[TestMethod]
+		public void ShouldConvertToJObject()
+		{
+			// arrange
+			var obj = new JsonTestClass
+			{
+				StringValue = "Hello JSON",
+				DecimalValue = 0.815m
+			};
+
+			// act
+			var jObj = obj.ConvertToJObject();
+
+			// assert
+			Assert.IsNotNull(jObj);
+			Assert.AreEqual(typeof(JObject), jObj.GetType());
+			Assert.AreEqual(obj.StringValue, jObj.Value<string>("stringValue"));
+			Assert.AreEqual(obj.DecimalValue, jObj.Value<decimal>("decimalValue"));
+			Assert.AreEqual(obj.LocalTimestamp.Kind, jObj.Value<DateTime>("localTimestamp").Kind);
+			Assert.AreEqual(obj.LocalTimestamp, jObj.Value<DateTime>("localTimestamp"));
+			Assert.AreEqual(obj.UtcTimestamp.Kind, jObj.Value<DateTime>("utcTimestamp").Kind);
+			Assert.AreEqual(obj.UtcTimestamp, jObj.Value<DateTime>("utcTimestamp"));
+		}
+
+		[TestMethod]
+		public void ShouldConvertToJArray()
+		{
+			// arrange
+			string[] stringArray = new[] { "one", "two", "three" };
+			var objectArray = new[]
+			{
+				new JsonTestClass { StringValue = "One" },
+				new JsonTestClass { StringValue = "Two" },
+				new JsonTestClass { StringValue = "Three" }
+			};
+
+			// act
+			var stringJArray = stringArray.ConvertToJArray();
+			var objectJArray = objectArray.ConvertToJArray();
+
+			// assert
+			Assert.IsNotNull(stringJArray);
+			Assert.AreEqual(typeof(JArray), stringJArray.GetType());
+			Assert.AreEqual(stringArray[0], stringJArray[0]);
+			Assert.AreEqual(stringArray[1], stringJArray[1]);
+			Assert.AreEqual(stringArray[2], stringJArray[2]);
+
+			Assert.IsNotNull(objectJArray);
+			Assert.AreEqual(typeof(JArray), objectJArray.GetType());
+			Assert.AreEqual(objectArray[0].StringValue, objectJArray[0].Value<string>("stringValue"));
+			Assert.AreEqual(objectArray[1].StringValue, objectJArray[1].Value<string>("stringValue"));
+			Assert.AreEqual(objectArray[2].StringValue, objectJArray[2].Value<string>("stringValue"));
+		}
+
+		[TestMethod]
+		public void ShouldRunJsonTreeWithoutDefault()
+		{
+			// arrange
+			var obj = new JsonTestClass { StringValue = "Running Json", Object = new JsonTestSubClass { IntegerValue = 4711 } };
+			var jObj = obj.ConvertToJObject();
+
+			// act
+			string topLevelString = jObj.GetValue<string>("stringValue");
+			decimal topLevelDecimal = jObj.GetValue<decimal>("decimalValue");
+			int subLevelInteger = jObj.GetValue<int>("object:integerValue");
+			string subLevelString = jObj.GetValue<string>("object:stringValue");
+
+			string notExistingOnTopLevel = jObj.GetValue<string>("fancyValue");
+			string notExistingOnSubLevel = jObj.GetValue<string>("object:fancyValue");
+			int? notExistingLevel = jObj.GetValue<int?>("fancy:int");
+
+			// assert
+			Assert.AreEqual(obj.StringValue, topLevelString);
+			Assert.AreEqual(obj.DecimalValue, topLevelDecimal);
+			Assert.AreEqual(obj.Object.IntegerValue, subLevelInteger);
+			Assert.AreEqual(obj.Object.StringValue, subLevelString);
+
+			Assert.IsNull(notExistingOnTopLevel);
+			Assert.IsNull(notExistingOnSubLevel);
+			Assert.IsNull(notExistingLevel);
+		}
+
+		[TestMethod]
+		public void ShouldRunJsonTreeWithDefault()
+		{
+			// arrange
+			var obj = new JsonTestClass { StringValue = "Running Json", Object = new JsonTestSubClass { IntegerValue = 4711 } };
+			var jObj = obj.ConvertToJObject();
+
+			// act
+			string topLevelString = jObj.GetValue("stringValue", "Test String");
+			decimal topLevelDecimal = jObj.GetValue("decimalValue", 13.24m);
+			int subLevelInteger = jObj.GetValue("object:integerValue", 55);
+			string subLevelString = jObj.GetValue("object:stringValue", "Yeah!");
+
+			string notExistingOnTopLevel = jObj.GetValue("fancyValue", "Party!");
+			string notExistingOnSubLevel = jObj.GetValue("object:fancyValue", "Well Done");
+			int? notExistingLevel = jObj.GetValue<int?>("fancy:int", 13);
+
+			// assert
+			Assert.AreEqual(obj.StringValue, topLevelString);
+			Assert.AreEqual(obj.DecimalValue, topLevelDecimal);
+			Assert.AreEqual(obj.Object.IntegerValue, subLevelInteger);
+			Assert.AreEqual(obj.Object.StringValue, subLevelString);
+
+			Assert.AreEqual("Party!", notExistingOnTopLevel);
+			Assert.AreEqual("Well Done", notExistingOnSubLevel);
+			Assert.AreEqual(13, notExistingLevel);
+		}
+
+		[TestMethod]
+		public void ShouldReturnNull()
+		{
+			// arrange
+			object obj = null;
+			IEnumerable list = null;
+			JObject jObj = null;
+
+			// act
+			var objTest = obj.ConvertToJObject();
+			var listTest = list.ConvertToJArray();
+			object getTest = jObj.GetValue<object>("Nothing");
+
+			// assert
+			Assert.IsNull(objTest);
+			Assert.IsNull(listTest);
+			Assert.IsNull(getTest);
+		}
+
+		[TestMethod]
+		public void ShouldHandleSerializationError()
+		{
+			// arrange
+			var obj = new JsonErrorClass();
+
+			// act
+			string json = obj.SerializeJson();
+
+			// assert
+			Assert.AreEqual("{}", json);
+		}
+	}
+}

UnitTests/Common/Extensions/ReaderWriterLockSlimExtensionsTests.cs

@@ -0,0 +1,221 @@
+using System;
+using System.Threading;
+using System.Threading.Tasks;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class ReaderWriterLockSlimExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldEnterReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+
+			// act
+			using var disposable = rwLock.GetReadLock();
+
+			// assert
+			Assert.IsNotNull(disposable);
+			Assert.IsTrue(rwLock.IsReadLockHeld);
+			Assert.IsFalse(rwLock.IsUpgradeableReadLockHeld);
+			Assert.IsFalse(rwLock.IsWriteLockHeld);
+		}
+
+		[TestMethod]
+		public void ShouldEnterUpgradeableReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+
+			// act
+			using var disposable = rwLock.GetUpgradeableReadLock();
+
+			// assert
+			Assert.IsNotNull(disposable);
+			Assert.IsFalse(rwLock.IsReadLockHeld);
+			Assert.IsTrue(rwLock.IsUpgradeableReadLockHeld);
+			Assert.IsFalse(rwLock.IsWriteLockHeld);
+		}
+
+		[TestMethod]
+		public void ShouldAllowWriteLockAfterUpgradableReadLock()
+		{
+			// arrange
+			var rwLockUsing = new ReaderWriterLockSlim();
+			var rwLockClassic = new ReaderWriterLockSlim();
+
+			// act
+			using var disposableReadUsing = rwLockUsing.GetUpgradeableReadLock();
+			using (rwLockUsing.GetWriteLock())
+			{
+				// assert
+				Assert.IsTrue(rwLockUsing.IsUpgradeableReadLockHeld);
+				Assert.IsTrue(rwLockUsing.IsWriteLockHeld);
+			}
+			// assert
+			Assert.IsTrue(rwLockUsing.IsUpgradeableReadLockHeld);
+			Assert.IsFalse(rwLockUsing.IsWriteLockHeld);
+
+			// act
+			using (rwLockClassic.GetUpgradeableReadLock())
+			{
+				rwLockClassic.EnterWriteLock();
+
+				// assert
+				Assert.IsTrue(rwLockClassic.IsUpgradeableReadLockHeld);
+				Assert.IsTrue(rwLockClassic.IsWriteLockHeld);
+			}
+			// assert
+			Assert.IsFalse(rwLockClassic.IsUpgradeableReadLockHeld);
+			Assert.IsFalse(rwLockClassic.IsWriteLockHeld);
+		}
+
+		[TestMethod]
+		public void ShouldEnterWriteLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+
+			// act
+			using var disposable = rwLock.GetWriteLock();
+
+			// assert
+			Assert.IsNotNull(disposable);
+			Assert.IsFalse(rwLock.IsReadLockHeld);
+			Assert.IsFalse(rwLock.IsUpgradeableReadLockHeld);
+			Assert.IsTrue(rwLock.IsWriteLockHeld);
+		}
+
+		[TestMethod]
+		public void ShouldNotAllowWriteLockAfterReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+
+			// act
+			using var disposableRead = rwLock.GetReadLock();
+			try
+			{
+				using var disposaleWrite = rwLock.GetWriteLock();
+				Assert.Fail();
+			}
+			catch (LockRecursionException)
+			{ }
+
+			// assert
+			Assert.IsNotNull(disposableRead);
+			Assert.IsTrue(rwLock.IsReadLockHeld);
+			Assert.IsFalse(rwLock.IsUpgradeableReadLockHeld);
+			Assert.IsFalse(rwLock.IsWriteLockHeld);
+		}
+
+		[TestMethod]
+		public void ShouldAllowWriteLockAfterUpgradeableReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+
+			// act
+			using var disposableRead = rwLock.GetUpgradeableReadLock();
+			using var disposableWrite = rwLock.GetWriteLock();
+
+			// assert
+			Assert.IsNotNull(disposableRead);
+			Assert.IsNotNull(disposableWrite);
+			Assert.IsFalse(rwLock.IsReadLockHeld);
+			Assert.IsTrue(rwLock.IsUpgradeableReadLockHeld);
+			Assert.IsTrue(rwLock.IsWriteLockHeld);
+		}
+
+		[TestMethod]
+		public void ShouldGetTimeoutOnReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+			bool isTimeout = false;
+
+			// act
+			using var disposableRead = rwLock.GetWriteLock();
+			var awaitableTask = Task.Run(() =>
+			{
+				try
+				{
+					using var disposableRead = rwLock.GetReadLock(10);
+					Assert.Fail();
+				}
+				catch (TimeoutException)
+				{
+					isTimeout = true;
+				}
+				catch (Exception)
+				{ /* keep it quiet */ }
+			});
+			Task.WaitAll(awaitableTask);
+
+			// assert
+			Assert.IsTrue(isTimeout);
+		}
+
+		[TestMethod]
+		public void ShouldGetTimeoutOnUpgradeableReadLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+			bool isTimeout = false;
+
+			// act
+			using var disposableRead = rwLock.GetWriteLock();
+			var awaitableTask = Task.Run(() =>
+			{
+				try
+				{
+					using var disposableRead = rwLock.GetUpgradeableReadLock(10);
+					Assert.Fail();
+				}
+				catch (TimeoutException)
+				{
+					isTimeout = true;
+				}
+				catch (Exception)
+				{ /* keep it quiet */ }
+			});
+			Task.WaitAll(awaitableTask);
+
+			// assert
+			Assert.IsTrue(isTimeout);
+		}
+
+		[TestMethod]
+		public void ShouldGetTimeoutOnWriteLock()
+		{
+			// arrange
+			var rwLock = new ReaderWriterLockSlim();
+			bool isTimeout = false;
+
+			// act
+			using var disposableRead = rwLock.GetReadLock();
+			var awaitableTask = Task.Run(() =>
+			{
+				try
+				{
+					using var disposableRead = rwLock.GetWriteLock(10);
+					Assert.Fail();
+				}
+				catch (TimeoutException)
+				{
+					isTimeout = true;
+				}
+				catch (Exception)
+				{ /* keep it quiet */ }
+			});
+			Task.WaitAll(awaitableTask);
+
+			// assert
+			Assert.IsTrue(isTimeout);
+		}
+	}
+}

UnitTests/Common/Extensions/StreamExtensionsTests.cs

@@ -0,0 +1,139 @@
+using System;
+using System.IO;
+using System.Text;
+using System.Threading.Tasks;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class StreamExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReadLineFromStreamSynchronous()
+		{
+			// arrange
+			var sb = new StringBuilder();
+			sb.AppendLine("First Line");
+			sb.AppendLine("Second Line");
+			byte[] buffer = Encoding.UTF8.GetBytes(sb.ToString().Trim());
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = stream.ReadLine();
+
+			// assert
+			Assert.AreEqual("First Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public void ShouldReadUntilEndAsLineSynchronous()
+		{
+			// arrange
+			byte[] buffer = Encoding.UTF8.GetBytes("Single Line");
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = stream.ReadLine();
+
+			// assert
+			Assert.AreEqual("Single Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public void ShouldReturnNullWhenNotReadableSynchronous()
+		{
+			// arrange
+			var stream = new WriteOnlyStream();
+
+			// act
+			string line = stream.ReadLine();
+
+			// assert
+			Assert.IsNull(line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public async Task ShouldReadLineFromStreamAsynchronous()
+		{
+			// arrange
+			var sb = new StringBuilder();
+			sb.AppendLine("First Line");
+			sb.AppendLine("Second Line");
+			byte[] buffer = Encoding.UTF8.GetBytes(sb.ToString().Trim());
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = await stream.ReadLineAsync();
+
+			// assert
+			Assert.AreEqual("First Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public async Task ShouldReadUntilEndAsLineAsynchronous()
+		{
+			// arrange
+			byte[] buffer = Encoding.UTF8.GetBytes("Single Line");
+			var stream = new MemoryStream(buffer);
+
+			// act
+			string line = await stream.ReadLineAsync();
+
+			// assert
+			Assert.AreEqual("Single Line", line);
+
+			stream.Dispose();
+		}
+
+		[TestMethod]
+		public async Task ShouldReturnNullWhenNotReadableAsynchronous()
+		{
+			// arrange
+			var stream = new WriteOnlyStream();
+
+			// act
+			string line = await stream.ReadLineAsync();
+
+			// assert
+			Assert.IsNull(line);
+
+			stream.Dispose();
+		}
+
+		private class WriteOnlyStream : Stream
+		{
+			public override bool CanRead => false;
+
+			public override bool CanSeek => false;
+
+			public override bool CanWrite => true;
+
+			public override long Length => 0;
+
+			public override long Position { get => 0; set => throw new NotImplementedException(); }
+
+			public override void Flush()
+			{ }
+
+			public override int Read(byte[] buffer, int offset, int count) => 0;
+
+			public override long Seek(long offset, SeekOrigin origin) => 0;
+
+			public override void SetLength(long value)
+			{ }
+
+			public override void Write(byte[] buffer, int offset, int count)
+			{ }
+		}
+	}
+}

UnitTests/Common/Extensions/StringExtensionsTests.cs

@@ -0,0 +1,353 @@
+using System;
+using System.Linq;
+using System.Net;
+using System.Text;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Extensions
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class StringExtensionsTests
+	{
+		[TestMethod]
+		public void ShouldReturnEmptyList()
+		{
+			// arrange
+			string hex = "";
+
+			// act
+			var bytes = hex.HexToBytes();
+
+			// assert
+			Assert.IsNotNull(bytes);
+			Assert.IsFalse(bytes.Any());
+		}
+
+		[TestMethod]
+		public void ShouldReturnEmptyListWhenInvalid()
+		{
+			// arrange
+			string hex1 = "aff";
+			string hex2 = "de:ad:be:e";
+			string hex3 = "hell";
+
+			// act
+			var bytes1 = hex1.HexToBytes();
+			var bytes2 = hex2.HexToBytes(":");
+			var bytes3 = hex3.HexToBytes();
+
+			// assert
+			Assert.IsNotNull(bytes1);
+			Assert.IsFalse(bytes1.Any());
+
+			Assert.IsNotNull(bytes2);
+			Assert.IsFalse(bytes2.Any());
+
+			Assert.IsNotNull(bytes3);
+			Assert.IsFalse(bytes3.Any());
+		}
+
+		[TestMethod]
+		public void ShouldConvertHexToBytes()
+		{
+			// arrange
+			string hex = "deadbeef";
+
+			// act
+			var bytes = hex.HexToBytes();
+
+			// assert
+			Assert.IsNotNull(bytes);
+			Assert.AreEqual(4, bytes.Count());
+			Assert.AreEqual(0xde, bytes.ElementAt(0));
+			Assert.AreEqual(0xad, bytes.ElementAt(1));
+			Assert.AreEqual(0xbe, bytes.ElementAt(2));
+			Assert.AreEqual(0xef, bytes.ElementAt(3));
+		}
+
+		[TestMethod]
+		public void ShouldConvertHexToBytesWithDelimiter()
+		{
+			// arrange
+			string hex = "af:fe";
+
+			// act
+			var bytes = hex.HexToBytes(":");
+
+			// assert
+			Assert.IsNotNull(bytes);
+			Assert.AreEqual(2, bytes.Count());
+			Assert.AreEqual(0xaf, bytes.ElementAt(0));
+			Assert.AreEqual(0xfe, bytes.ElementAt(1));
+		}
+
+		[TestMethod]
+		public void ShouldReturnNullWhenInvalid()
+		{
+			// arrange
+			byte[] bytes1 = null;
+			byte[] bytes2 = Array.Empty<byte>();
+
+			// act
+			string hex1 = bytes1.BytesToHex();
+			string hex2 = bytes2.BytesToHex();
+
+			// assert
+			Assert.IsNull(hex1);
+			Assert.IsNull(hex2);
+		}
+
+		[TestMethod]
+		public void ShouldReturnHexString()
+		{
+			// arrange
+			byte[] bytes = new byte[] { 0xaf, 0xfe };
+
+			// act
+			string hex = bytes.BytesToHex();
+
+			// assert
+			Assert.IsNotNull(hex);
+			Assert.AreEqual("affe", hex);
+		}
+
+		[TestMethod]
+		public void ShouldReturnHexStringWithDelimiter()
+		{
+			// arrange
+			byte[] bytes = new byte[] { 0xde, 0xad, 0xbe, 0xef };
+
+			// act
+			string hex = bytes.BytesToHex("_");
+
+			// assert
+			Assert.IsNotNull(hex);
+			Assert.AreEqual("de_ad_be_ef", hex);
+		}
+
+		[TestMethod]
+		public void ShouldEncodeStringToHex()
+		{
+			// arrange
+			string plain = "Hello";
+
+			// act
+			string hex1 = plain.HexEncode();
+			string hex2 = plain.HexEncode(Encoding.Default);
+
+			// assert
+			Assert.AreEqual("48656c6c6f", hex1);
+			Assert.AreEqual("48656c6c6f", hex2);
+		}
+
+		[TestMethod]
+		public void ShouldDecodeStringFromHex()
+		{
+			// arrange
+			string hex = "48656c6c6f";
+
+			// act
+			string plain1 = hex.HexDecode();
+			string plain2 = hex.HexDecode(Encoding.Default);
+
+			// assert
+			Assert.AreEqual("Hello", plain1);
+			Assert.AreEqual("Hello", plain2);
+		}
+
+		[TestMethod]
+		public void ShouldEncodeStringToBase64()
+		{
+			// arrange
+			string plain = "Hello";
+
+			// act
+			string base641 = plain.Base64Encode();
+			string base642 = plain.Base64Encode(Encoding.Default);
+
+			// assert
+			Assert.AreEqual("SGVsbG8=", base641);
+			Assert.AreEqual("SGVsbG8=", base642);
+		}
+
+		[TestMethod]
+		public void ShouldDecodeStringFromBase64()
+		{
+			// arrange
+			string base64 = "SGVsbG8=";
+
+			// act
+			string plain1 = base64.Base64Decode();
+			string plain2 = base64.Base64Decode(Encoding.Default);
+
+			// assert
+			Assert.AreEqual("Hello", plain1);
+			Assert.AreEqual("Hello", plain2);
+		}
+
+		[TestMethod]
+		public void ShouldReplaceStart()
+		{
+			// arrange
+			string str = "Hello World!";
+
+			// act
+			string test1 = str.ReplaceStart("Hello", "Bye");
+			string test2 = str.ReplaceStart("World!", "Mars?");
+
+			// assert
+			Assert.AreNotEqual(str, test1);
+			Assert.AreEqual("Bye World!", test1);
+
+			Assert.AreEqual(str, test2);
+			Assert.AreNotEqual("Hello Mars?", test2);
+		}
+
+		[TestMethod]
+		public void ShouldReplaceEnd()
+		{
+			// arrange
+			string str = "Hello World!";
+
+			// act
+			string test1 = str.ReplaceEnd("Hello", "Bye");
+			string test2 = str.ReplaceEnd("World!", "Mars?");
+
+			// assert
+			Assert.AreEqual(str, test1);
+			Assert.AreNotEqual("Bye World!", test1);
+
+			Assert.AreNotEqual(str, test2);
+			Assert.AreEqual("Hello Mars?", test2);
+		}
+
+		[TestMethod]
+		public void ShouldParseDecimal()
+		{
+			// arrange
+			decimal number = 1234.56m;
+			string stringNumberEn = "1234.56";
+			string stringNumberDe = "1234,56";
+
+			// act
+			decimal numberEn = stringNumberEn.ParseDecimal();
+			decimal numberDe = stringNumberDe.ParseDecimal();
+
+			// assert
+			Assert.AreEqual(number, numberEn);
+			Assert.AreEqual(number, numberDe);
+		}
+
+		[TestMethod]
+		public void ShouldParseDecimalWithThousandsSeparator()
+		{
+			// arrange
+			decimal number = 1234.56m;
+			string stringNumberEn = "1,234.56";
+			string stringNumberDe = "1.234,56";
+
+			// act
+			decimal numberEn = stringNumberEn.ParseDecimal();
+			decimal numberDe = stringNumberDe.ParseDecimal();
+
+			// assert
+			Assert.AreEqual(number, numberEn);
+			Assert.AreEqual(number, numberDe);
+		}
+
+		[TestMethod]
+		public void ShouldValidateEmailAddressWithoutRecordCheck()
+		{
+			// arrange
+			string validEmailWithoutTag = "test@gmail.com";
+			string validEmailWithTag = "test+tag@not.exists";
+			string invalidEmailWithoutTag = "<Test Account> test@gmail.com";
+			string invalidEmailWithTag = "<Test Account> test+tag@not.exists";
+			string nullStr = null;
+
+			// act
+			bool validWithoutTag = validEmailWithoutTag.IsValidEmailAddress(checkRecordExists: false);
+			bool validWithTag = validEmailWithTag.IsValidEmailAddress(checkRecordExists: false);
+			bool invalidWithoutTag = !invalidEmailWithoutTag.IsValidEmailAddress(checkRecordExists: false);
+			bool invalidWithTag = !invalidEmailWithTag.IsValidEmailAddress(checkRecordExists: false);
+			bool nullTest = nullStr.IsValidEmailAddress(checkRecordExists: false);
+
+			// assert
+			Assert.IsTrue(validWithoutTag);
+			Assert.IsTrue(validWithTag);
+			Assert.IsTrue(invalidWithoutTag);
+			Assert.IsTrue(invalidWithTag);
+			Assert.IsFalse(nullTest);
+		}
+
+		[TestMethod]
+		public void ShouldValidateEmailAddressWithRecordCheck()
+		{
+			// arrange
+			string validEmail = "test@gmail.com";
+			string invalidEmail = "test@not.exists";
+
+			// act
+			bool valid = validEmail.IsValidEmailAddress(checkRecordExists: true);
+			bool invalid = !invalidEmail.IsValidEmailAddress(checkRecordExists: true);
+
+			// assert
+			Assert.IsTrue(valid);
+			Assert.IsTrue(invalid);
+		}
+
+		[TestMethod]
+		public void ShouldValidateEmailAddressWithRecordCheckDefinedNameservers()
+		{
+			// arrange
+			string validEmail = "test@gmail.com";
+			string invalidEmail = "test@not.exists";
+			var nameserver = new IPEndPoint(IPAddress.Parse("1.1.1.1"), 53);
+
+			// act
+			bool valid = validEmail.IsValidEmailAddress(new[] { nameserver });
+			bool invalid = !invalidEmail.IsValidEmailAddress(new[] { nameserver });
+
+			// assert
+			Assert.IsTrue(valid);
+			Assert.IsTrue(invalid);
+		}
+
+		[TestMethod]
+		public void ShouldWorkWithNullOrEmptyString()
+		{
+			// arrange
+			string nullStr = null;
+			string emptyStr = "";
+
+			// act
+			string hexEncodeNull = nullStr.HexEncode();
+			string hexEncodeEmpty = emptyStr.HexEncode();
+			string hexDecodeNull = nullStr.HexDecode();
+			string hexDecodeEmpty = emptyStr.HexDecode();
+
+			// assert
+			Assert.IsNull(hexEncodeNull);
+			Assert.AreEqual("", hexEncodeEmpty);
+			Assert.IsNull(hexDecodeNull);
+			Assert.AreEqual("", hexDecodeEmpty);
+		}
+
+		[TestMethod]
+		public void ShouldAddCustomLineTermination()
+		{
+			// arrange
+			string value = "abc";
+			var sb = new StringBuilder();
+
+			// act
+			sb.AppendLine(value, "\r");
+			sb.AppendLine(value, "\r");
+
+			// assert
+			Assert.AreEqual($"{value}\r{value}\r", sb.ToString());
+			Assert.IsFalse(sb.ToString().Contains('\n'));
+		}
+	}
+}

UnitTests/Common/Utilities/CryptographyHelperTests.cs

@@ -0,0 +1,635 @@
+using System;
+using System.Diagnostics;
+using System.IO;
+using System.Security.Cryptography;
+using System.Text.RegularExpressions;
+using UnitTests.Common.Utils;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Utilities
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class CryptographyHelperTests
+	{
+		private string keyFile;
+		private CryptographyHelper cryptoHelper;
+
+		[TestInitialize]
+		public void Initialize()
+		{
+			keyFile = Path.GetTempFileName();
+			cryptoHelper = new CryptographyHelper(keyFile);
+		}
+
+		[TestCleanup]
+		public void Cleanup()
+		{
+			File.Delete(keyFile);
+		}
+
+		#region Static
+
+		#region Encryption
+
+		#region AES
+
+		[TestMethod]
+		public void ShouldEncryptAesWithoutSalt()   // required to test the encryption itself
+		{
+			// arrange
+			using var _ = CryptographyHelperSaltMock.Create(0);
+
+			byte[] bytes = new byte[] { 0xaf, 0xfe };
+			string str = "ABC";
+			string password1 = "P@ssw0rd!";
+			string password2 = "P@ssw0rd";
+
+			byte[] expectedBytes = new byte[] { 0x7c, 0x7b, 0x77, 0x56, 0x91, 0x1a, 0xd9, 0xc0, 0x72, 0x70, 0x36, 0x88, 0x9f, 0xb4, 0xb5, 0xbc };
+
+			// act
+			byte[] cipherBytes1 = CryptographyHelper.AesEncrypt(bytes, password1);
+			string cipherStr1 = CryptographyHelper.AesEncrypt(str, password1);
+			byte[] cipherBytes2 = CryptographyHelper.AesEncrypt(bytes, password2);
+			string cipherStr2 = CryptographyHelper.AesEncrypt(str, password2);
+
+			// assert
+			CollectionAssert.AreEqual(expectedBytes, cipherBytes1);
+			Assert.AreEqual("ueLuhFNpCuYmx8v3hczHtg==", cipherStr1);
+
+			CollectionAssert.AreNotEqual(expectedBytes, cipherBytes2);
+			Assert.AreNotEqual("ueLuhFNpCuYmx8v3hczHtg==", cipherStr2);
+		}
+
+		[TestMethod]
+		public void ShouldDecryptAesWithoutSalt()   // required to test the decryption itself
+		{
+			// arrange
+			using var _ = CryptographyHelperSaltMock.Create(0);
+
+			string cipherStr = "ueLuhFNpCuYmx8v3hczHtg==";
+			byte[] cipherBytes = new byte[] { 0x7c, 0x7b, 0x77, 0x56, 0x91, 0x1a, 0xd9, 0xc0, 0x72, 0x70, 0x36, 0x88, 0x9f, 0xb4, 0xb5, 0xbc };
+
+			string password1 = "P@ssw0rd!";
+			string password2 = "P@ssw0rd";
+
+			byte[] expectedBytes = new byte[] { 0xaf, 0xfe };
+
+			// act
+			byte[] plainBytes1 = CryptographyHelper.AesDecrypt(cipherBytes, password1);
+			string plainStr1 = CryptographyHelper.AesDecrypt(cipherStr, password1);
+
+			try
+			{
+				CryptographyHelper.AesDecrypt(cipherBytes, password2);
+				Assert.Fail();
+			}
+			catch (CryptographicException)
+			{ }
+
+			try
+			{
+				CryptographyHelper.AesDecrypt(cipherStr, password2);
+				Assert.Fail();
+			}
+			catch (CryptographicException)
+			{ }
+
+			// assert
+			CollectionAssert.AreEqual(expectedBytes, plainBytes1);
+			Assert.AreEqual("ABC", plainStr1);
+		}
+
+		[TestMethod]
+		public void ShouldEncryptDecryptAesBytes()
+		{
+			// arrange
+			byte[] plain = new byte[] { 0xaf, 0xfe };
+			string password = "P@ssw0rd!";
+
+			// act
+			byte[] cipher1 = CryptographyHelper.AesEncrypt(plain, password);
+			byte[] cipher2 = CryptographyHelper.AesEncrypt(plain, password);
+
+			byte[] plain1 = CryptographyHelper.AesDecrypt(cipher1, password);
+			byte[] plain2 = CryptographyHelper.AesDecrypt(cipher2, password);
+
+			// assert
+			CollectionAssert.AreNotEqual(cipher1, cipher2);
+			Assert.AreEqual(24, cipher1.Length);
+			Assert.AreEqual(24, cipher2.Length);
+			CollectionAssert.AreEqual(plain, plain1);
+			CollectionAssert.AreEqual(plain, plain2);
+		}
+
+		[TestMethod]
+		public void ShouldEncryptDecryptAesString()
+		{
+			// arrange
+			string plain = "ABC";
+			string password = "P@ssw0rd!";
+
+			// act
+			string cipher1 = CryptographyHelper.AesEncrypt(plain, password);
+			string cipher2 = CryptographyHelper.AesEncrypt(plain, password);
+
+			string plain1 = CryptographyHelper.AesDecrypt(cipher1, password);
+			string plain2 = CryptographyHelper.AesDecrypt(cipher2, password);
+
+			// assert
+			Assert.AreNotEqual(cipher1, cipher2);
+			Assert.AreEqual(32, cipher1.Length);
+			Assert.AreEqual(32, cipher2.Length);
+			Assert.AreEqual(plain, plain1);
+			Assert.AreEqual(plain, plain2);
+		}
+
+		#endregion AES
+
+		#region TripleDES
+
+		[TestMethod]
+		public void ShouldEncryptTdesWithoutSalt()   // required to test the encryption itself
+		{
+			// arrange
+			using var _ = CryptographyHelperSaltMock.Create(0);
+
+			byte[] bytes = new byte[] { 0xaf, 0xfe };
+			string str = "ABC";
+			string password1 = "P@ssw0rd!";
+			string password2 = "P@ssw0rd";
+
+			byte[] expectedBytes = new byte[] { 0xbf, 0x59, 0x1f, 0x48, 0x69, 0xab, 0x18, 0xc7 };
+
+			// act
+			byte[] cipherBytes1 = CryptographyHelper.TripleDesEncrypt(bytes, password1);
+			string cipherStr1 = CryptographyHelper.TripleDesEncrypt(str, password1);
+			byte[] cipherBytes2 = CryptographyHelper.TripleDesEncrypt(bytes, password2);
+			string cipherStr2 = CryptographyHelper.TripleDesEncrypt(str, password2);
+
+			// assert
+			CollectionAssert.AreEqual(expectedBytes, cipherBytes1);
+			Assert.AreEqual("1l74soBuuEI=", cipherStr1);
+
+			CollectionAssert.AreNotEqual(expectedBytes, cipherBytes2);
+			Assert.AreNotEqual("1l74soBuuEI=", cipherStr2);
+		}
+
+		[TestMethod]
+		public void ShouldDecryptTdesWithoutSalt()   // required to test the decryption itself
+		{
+			// arrange
+			using var _ = CryptographyHelperSaltMock.Create(0);
+
+			string cipherStr = "1l74soBuuEI=";
+			byte[] cipherBytes = new byte[] { 0xbf, 0x59, 0x1f, 0x48, 0x69, 0xab, 0x18, 0xc7 };
+
+			string password1 = "P@ssw0rd!";
+			string password2 = "P@ssw0rd";
+
+			byte[] expectedBytes = new byte[] { 0xaf, 0xfe };
+
+			// act
+			byte[] plainBytes1 = CryptographyHelper.TripleDesDecrypt(cipherBytes, password1);
+			string plainStr1 = CryptographyHelper.TripleDesDecrypt(cipherStr, password1);
+
+			try
+			{
+				CryptographyHelper.TripleDesDecrypt(cipherBytes, password2);
+				Assert.Fail();
+			}
+			catch (CryptographicException)
+			{ }
+
+			try
+			{
+				CryptographyHelper.TripleDesDecrypt(cipherStr, password2);
+				Assert.Fail();
+			}
+			catch (CryptographicException)
+			{ }
+
+			// assert
+			CollectionAssert.AreEqual(expectedBytes, plainBytes1);
+			Assert.AreEqual("ABC", plainStr1);
+		}
+
+		[TestMethod]
+		public void ShouldEncryptDecryptTdesBytes()
+		{
+			// arrange
+			byte[] plain = new byte[] { 0xaf, 0xfe };
+			string password = "P@ssw0rd!";
+
+			// act
+			byte[] cipher1 = CryptographyHelper.TripleDesEncrypt(plain, password);
+			byte[] cipher2 = CryptographyHelper.TripleDesEncrypt(plain, password);
+
+			byte[] plain1 = CryptographyHelper.TripleDesDecrypt(cipher1, password);
+			byte[] plain2 = CryptographyHelper.TripleDesDecrypt(cipher2, password);
+
+			// assert
+			CollectionAssert.AreNotEqual(cipher1, cipher2);
+			Assert.AreEqual(16, cipher1.Length);
+			Assert.AreEqual(16, cipher2.Length);
+			CollectionAssert.AreEqual(plain, plain1);
+			CollectionAssert.AreEqual(plain, plain2);
+		}
+
+		[TestMethod]
+		public void ShouldEncryptDecryptTdesString()
+		{
+			// arrange
+			string plain = "ABC";
+			string password = "P@ssw0rd!";
+
+			// act
+			string cipher1 = CryptographyHelper.TripleDesEncrypt(plain, password);
+			string cipher2 = CryptographyHelper.TripleDesEncrypt(plain, password);
+
+			string plain1 = CryptographyHelper.TripleDesDecrypt(cipher1, password);
+			string plain2 = CryptographyHelper.TripleDesDecrypt(cipher2, password);
+
+			// assert
+			Assert.AreNotEqual(cipher1, cipher2);
+			Assert.AreEqual(24, cipher1.Length);
+			Assert.AreEqual(24, cipher2.Length);
+			Assert.AreEqual(plain, plain1);
+			Assert.AreEqual(plain, plain2);
+		}
+
+		#endregion TripleDES
+
+		#endregion Encryption
+
+		#region Hash
+
+		[TestMethod]
+		public void ShouldReturnMd5Hash()
+		{
+			// arrange
+			string text = "Hello World!";
+			byte[] bytes = new byte[] { 0xde, 0xad, 0xbe, 0xef };
+			string fileName = Path.GetTempFileName();
+
+			// act
+			string textHash = CryptographyHelper.Md5(text);
+			string bytesHash = CryptographyHelper.Md5(bytes);
+
+			File.WriteAllText(fileName, text);
+			string fileHash = CryptographyHelper.Md5File(fileName);
+			File.Delete(fileName);
+
+			// assert
+			Assert.AreEqual("ed076287532e86365e841e92bfc50d8c", textHash);
+			Assert.AreEqual("2f249230a8e7c2bf6005ccd2679259ec", bytesHash);
+			Assert.AreEqual("ed076287532e86365e841e92bfc50d8c", fileHash);
+		}
+
+		[TestMethod]
+		public void ShouldReturnSha1Hash()
+		{
+			// arrange
+			string text = "Hello World!";
+			byte[] bytes = new byte[] { 0xde, 0xad, 0xbe, 0xef };
+			string fileName = Path.GetTempFileName();
+
+			// act
+			string textHash = CryptographyHelper.Sha1(text);
+			string bytesHash = CryptographyHelper.Sha1(bytes);
+
+			File.WriteAllText(fileName, text);
+			string fileHash = CryptographyHelper.Sha1File(fileName);
+			File.Delete(fileName);
+
+			// assert
+			Assert.AreEqual("2ef7bde608ce5404e97d5f042f95f89f1c232871", textHash);
+			Assert.AreEqual("d78f8bb992a56a597f6c7a1fb918bb78271367eb", bytesHash);
+			Assert.AreEqual("2ef7bde608ce5404e97d5f042f95f89f1c232871", fileHash);
+		}
+
+		[TestMethod]
+		public void ShouldReturnSha256Hash()
+		{
+			// arrange
+			string text = "Hello World!";
+			byte[] bytes = new byte[] { 0xde, 0xad, 0xbe, 0xef };
+			string fileName = Path.GetTempFileName();
+
+			// act
+			string textHash = CryptographyHelper.Sha256(text);
+			string bytesHash = CryptographyHelper.Sha256(bytes);
+
+			File.WriteAllText(fileName, text);
+			string fileHash = CryptographyHelper.Sha256File(fileName);
+			File.Delete(fileName);
+
+			// assert
+			Assert.AreEqual("7f83b1657ff1fc53b92dc18148a1d65dfc2d4b1fa3d677284addd200126d9069", textHash);
+			Assert.AreEqual("5f78c33274e43fa9de5659265c1d917e25c03722dcb0b8d27db8d5feaa813953", bytesHash);
+			Assert.AreEqual("7f83b1657ff1fc53b92dc18148a1d65dfc2d4b1fa3d677284addd200126d9069", fileHash);
+		}
+
+		[TestMethod]
+		public void ShouldReturnSha512Hash()
+		{
+			// arrange
+			string text = "Hello World!";
+			byte[] bytes = new byte[] { 0xde, 0xad, 0xbe, 0xef };
+			string fileName = Path.GetTempFileName();
+
+			// act
+			string textHash = CryptographyHelper.Sha512(text);
+			string bytesHash = CryptographyHelper.Sha512(bytes);
+
+			File.WriteAllText(fileName, text);
+			string fileHash = CryptographyHelper.Sha512File(fileName);
+			File.Delete(fileName);
+
+			// assert
+			Assert.AreEqual("861844d6704e8573fec34d967e20bcfef3d424cf48be04e6dc08f2bd58c729743371015ead891cc3cf1c9d34b49264b510751b1ff9e537937bc46b5d6ff4ecc8", textHash);
+			Assert.AreEqual("1284b2d521535196f22175d5f558104220a6ad7680e78b49fa6f20e57ea7b185d71ec1edb137e70eba528dedb141f5d2f8bb53149d262932b27cf41fed96aa7f", bytesHash);
+			Assert.AreEqual("861844d6704e8573fec34d967e20bcfef3d424cf48be04e6dc08f2bd58c729743371015ead891cc3cf1c9d34b49264b510751b1ff9e537937bc46b5d6ff4ecc8", fileHash);
+		}
+
+		#endregion Hash
+
+		#region Random
+
+		[TestMethod]
+		public void ShouldReturnRandomBytes()
+		{
+			// arrange
+			int length1 = 12;
+			int length2 = 12;
+			int length3 = 42;
+
+			// act
+			byte[] bytes1 = CryptographyHelper.GetRandomBytes(length1);
+			byte[] bytes2 = CryptographyHelper.GetRandomBytes(length2);
+			byte[] bytes3 = CryptographyHelper.GetRandomBytes(length3);
+
+			// assert
+			Assert.AreEqual(length1, bytes1.Length);
+			Assert.AreEqual(length2, bytes2.Length);
+			Assert.AreEqual(length3, bytes3.Length);
+
+			Assert.IsTrue(bytes1.Length == bytes2.Length);
+			CollectionAssert.AreNotEqual(bytes1, bytes2);
+		}
+
+		[TestMethod]
+		public void ShouldReturnRandomString()
+		{
+			// arrange
+			int length1 = 12;
+			int length2 = 12;
+			int length3 = 42;
+
+			// act
+			string str1 = CryptographyHelper.GetRandomString(length1);
+			string str2 = CryptographyHelper.GetRandomString(length2);
+			string str3 = CryptographyHelper.GetRandomString(length3);
+
+			// assert
+			Assert.AreEqual(length1, str1.Length);
+			Assert.AreEqual(length2, str2.Length);
+			Assert.AreEqual(length3, str3.Length);
+
+			Assert.IsTrue(str1.Length == str2.Length);
+			Assert.IsFalse(str1 == str2);
+		}
+
+		[TestMethod]
+		public void ShouldReturnRandomStringWithPool()
+		{
+			// arrange
+			int length = 12;
+			string pool = "0123456789abcdef";
+
+			// act
+			string str1 = CryptographyHelper.GetRandomString(length, pool);
+			string str2 = CryptographyHelper.GetRandomString(length, pool);
+
+			// assert
+			Assert.AreEqual(length, str1.Length);
+			Assert.AreEqual(length, str2.Length);
+			Assert.IsFalse(str1 == str2);
+			Assert.IsFalse(Regex.IsMatch(str1, "[^0-9a-f]"));
+			Assert.IsFalse(Regex.IsMatch(str2, "[^0-9a-f]"));
+		}
+
+		#endregion Random
+
+		#region Secure probing
+
+		[TestMethod]
+		public void ShouldTakeSameTimeToCompareString()
+		{
+			// arrange
+			string str1 = "Hello World!";
+			string str2 = "Hello World!";
+			string str3 = "Hallo World!";
+			string str4 = "Hello World?";
+			string nullStr = null;
+			string strLen = "Hello World";
+
+			var sw = new Stopwatch();
+
+			// act
+			bool nullCompare = CryptographyHelper.SecureEquals(nullStr, str1);
+			bool lenCompare = CryptographyHelper.SecureEquals(strLen, str1);
+
+			sw.Start();
+			bool compare1 = CryptographyHelper.SecureEquals(str1, str2);
+			long time1 = sw.ElapsedMilliseconds;
+
+			bool compare2 = CryptographyHelper.SecureEquals(str1, str3);
+			long time2 = sw.ElapsedMilliseconds;
+
+			bool compare3 = CryptographyHelper.SecureEquals(str1, str4);
+			long time3 = sw.ElapsedMilliseconds;
+			sw.Stop();
+
+			// assert
+			Assert.IsFalse(nullCompare);
+			Assert.IsFalse(lenCompare);
+			Assert.IsTrue(compare1);
+			Assert.IsFalse(compare2);
+			Assert.IsFalse(compare3);
+
+			Assert.AreEqual(time1, time2);
+			Assert.AreEqual(time1, time3);
+			Assert.AreEqual(time2, time3);
+		}
+
+		[TestMethod]
+		public void ShouldTakeSameTimeToCompareBytes()
+		{
+			// arrange
+			byte[] bytes1 = CryptographyHelper.GetRandomBytes(200);
+			byte[] bytes2 = new byte[bytes1.Length];
+			byte[] bytes3 = new byte[bytes1.Length];
+			byte[] bytes4 = new byte[bytes1.Length];
+			byte[] nullBytes = null;
+			byte[] lenBytes = new byte[bytes1.Length + 1];
+
+			Array.Copy(bytes1, bytes2, bytes1.Length);
+			Array.Copy(bytes1, bytes3, bytes1.Length);
+			Array.Copy(bytes1, bytes4, bytes1.Length);
+
+			bytes3[10] = (byte)(bytes1[10] + 1);
+			bytes4[190] = (byte)(bytes1[190] + 1);
+
+			var sw = new Stopwatch();
+
+			// act
+			bool nullCompare = CryptographyHelper.SecureEquals(nullBytes, bytes1);
+			bool lenCompare = CryptographyHelper.SecureEquals(lenBytes, bytes1);
+
+			sw.Start();
+			bool compare1 = CryptographyHelper.SecureEquals(bytes1, bytes2);
+			long time1 = sw.ElapsedMilliseconds;
+
+			bool compare2 = CryptographyHelper.SecureEquals(bytes1, bytes3);
+			long time2 = sw.ElapsedMilliseconds;
+
+			bool compare3 = CryptographyHelper.SecureEquals(bytes1, bytes4);
+			long time3 = sw.ElapsedMilliseconds;
+			sw.Stop();
+
+			// assert
+			Assert.IsFalse(nullCompare);
+			Assert.IsFalse(lenCompare);
+			Assert.IsTrue(compare1);
+			Assert.IsFalse(compare2);
+			Assert.IsFalse(compare3);
+
+			Assert.AreEqual(time1, time2);
+			Assert.AreEqual(time1, time3);
+			Assert.AreEqual(time2, time3);
+		}
+
+		#endregion Secure probing
+
+		#endregion Static
+
+		#region Instance
+
+		[TestMethod]
+		public void ShouldCreateDefaultFile()
+		{
+			// arrange
+			string executingAssemblyDir = AppContext.BaseDirectory;
+			string filePath = Path.Combine(executingAssemblyDir, "crypto.key");
+
+			// act
+			bool fileExistsBefore = File.Exists(filePath);
+			var helper = new CryptographyHelper();
+			bool fileExistsAfter = File.Exists(filePath);
+			string content = fileExistsAfter ? File.ReadAllText(filePath) : null;
+			File.Delete(filePath);
+
+			// assert
+			Assert.IsFalse(fileExistsBefore);
+			Assert.IsNotNull(helper);
+			Assert.IsTrue(fileExistsAfter);
+			Assert.IsTrue(!string.IsNullOrWhiteSpace(content));
+		}
+
+
+		[TestMethod]
+		public void ShouldEncryptAesUsingKeyFile()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = CryptographyHelper.GetRandomBytes(32);
+
+			string password = File.ReadAllText(keyFile);
+
+			// act
+			string cipherStr = cryptoHelper.EncryptAes(str);
+			byte[] cipherBytes = cryptoHelper.EncryptAes(bytes);
+
+			string plainStr = CryptographyHelper.AesDecrypt(cipherStr, password);
+			byte[] plainBytes = CryptographyHelper.AesDecrypt(cipherBytes, password);
+
+			// assert
+			Assert.AreNotEqual(str, cipherStr);
+			Assert.AreEqual(str, plainStr);
+			CollectionAssert.AreNotEqual(bytes, cipherBytes);
+			CollectionAssert.AreEqual(bytes, plainBytes);
+		}
+
+		[TestMethod]
+		public void ShouldDecryptAesUsingKeyFile()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = CryptographyHelper.GetRandomBytes(32);
+
+			string password = File.ReadAllText(keyFile);
+
+			// act
+			string cipherStr = CryptographyHelper.AesEncrypt(str, password);
+			byte[] cipherBytes = CryptographyHelper.AesEncrypt(bytes, password);
+
+			string plainStr = cryptoHelper.DecryptAes(cipherStr);
+			byte[] plainBytes = cryptoHelper.DecryptAes(cipherBytes);
+
+			// assert
+			Assert.AreNotEqual(str, cipherStr);
+			Assert.AreEqual(str, plainStr);
+			CollectionAssert.AreNotEqual(bytes, cipherBytes);
+			CollectionAssert.AreEqual(bytes, plainBytes);
+		}
+
+		[TestMethod]
+		public void ShouldEncryptTdesUsingKeyFile()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = CryptographyHelper.GetRandomBytes(32);
+
+			string password = File.ReadAllText(keyFile);
+
+			// act
+			string cipherStr = cryptoHelper.EncryptTripleDes(str);
+			byte[] cipherBytes = cryptoHelper.EncryptTripleDes(bytes);
+
+			string plainStr = CryptographyHelper.TripleDesDecrypt(cipherStr, password);
+			byte[] plainBytes = CryptographyHelper.TripleDesDecrypt(cipherBytes, password);
+
+			// assert
+			Assert.AreNotEqual(str, cipherStr);
+			Assert.AreEqual(str, plainStr);
+			CollectionAssert.AreNotEqual(bytes, cipherBytes);
+			CollectionAssert.AreEqual(bytes, plainBytes);
+		}
+
+		[TestMethod]
+		public void ShouldDecryptTdesUsingKeyFile()
+		{
+			// arrange
+			string str = "Hello World!";
+			byte[] bytes = CryptographyHelper.GetRandomBytes(32);
+
+			string password = File.ReadAllText(keyFile);
+
+			// act
+			string cipherStr = CryptographyHelper.TripleDesEncrypt(str, password);
+			byte[] cipherBytes = CryptographyHelper.TripleDesEncrypt(bytes, password);
+
+			string plainStr = cryptoHelper.DecryptTripleDes(cipherStr);
+			byte[] plainBytes = cryptoHelper.DecryptTripleDes(cipherBytes);
+
+			// assert
+			Assert.AreNotEqual(str, cipherStr);
+			Assert.AreEqual(str, plainStr);
+			CollectionAssert.AreNotEqual(bytes, cipherBytes);
+			CollectionAssert.AreEqual(bytes, plainBytes);
+		}
+
+		#endregion Instance
+	}
+}

UnitTests/Common/Utilities/DelayedTaskTests.cs

@@ -0,0 +1,288 @@
+using System;
+using System.Diagnostics;
+using System.Threading;
+using System.Threading.Tasks;
+using AMWD.Common.Utilities;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Utilities
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class DelayedTaskTests
+	{
+		[TestMethod]
+		public void ShouldCreateNewDelayedTaskNotStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Create(action, delay);
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(0, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldCreateNewDelayedTaskStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Run(action, delay);
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldRunOnceAfterReset()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Create(action, delay);
+			delayedTask.Reset();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldCancelWaitingTask()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTask = DelayedTask.Run(action, delay);
+			delayedTask.Cancel();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(0, executionCount);
+		}
+
+		[TestMethod]
+		public async Task ShouldResetRunningDelay()
+		{
+			// arrange
+			int executionCount = 0;
+			var sw = new Stopwatch();
+
+			var delay = TimeSpan.FromMilliseconds(200);
+			var action = () => { sw.Stop(); executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			sw.Start();
+			var delayedTask = DelayedTask.Run(action, delay);
+			await Task.Delay(50);
+			delayedTask.Reset();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+			// delta of 60ms as the precision below 50ms is really bad for System.Timer
+			Assert.AreEqual(250, sw.ElapsedMilliseconds, 60);
+		}
+
+		[TestMethod]
+		public async Task ShouldNotExecutedImmediateOnCreated()
+		{
+			// arrange
+			int executionCount = 0;
+			var sw = new Stopwatch();
+
+			var delay = TimeSpan.FromMilliseconds(200);
+			var action = () => { sw.Stop(); executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			sw.Start();
+			var delayedTask = DelayedTask.Create(action, delay);
+			await Task.Delay(50);
+			bool isSuccess = delayedTask.ExecutePending();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+			sw.Stop();
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(0, executionCount);
+			// delta of 60ms as the precision below 50ms is really bad for System.Timer
+			Assert.AreEqual(1250, sw.ElapsedMilliseconds, 60);
+			Assert.IsFalse(isSuccess);
+		}
+
+		[TestMethod]
+		public async Task ShouldExecuteImmediateOnExecutePendingWhenRunning()
+		{
+			// arrange
+			int executionCount = 0;
+			var sw = new Stopwatch();
+
+			var delay = TimeSpan.FromMilliseconds(200);
+			var action = () => { sw.Stop(); executionCount++; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			sw.Start();
+			var delayedTask = DelayedTask.Run(action, delay);
+			await Task.Delay(50);
+			bool isSuccess = delayedTask.ExecutePending();
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.AreEqual(delay, delayedTask.Delay);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+			// delta of 60ms as the precision below 50ms is really bad for System.Timer
+			Assert.AreEqual(50, sw.ElapsedMilliseconds, 60);
+			Assert.IsTrue(isSuccess);
+		}
+
+		[TestMethod]
+		public void ShouldReturnAnAwaiter()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+			var delayedTask = DelayedTask.Create(action, delay);
+
+			// act
+			delayedTask.Reset();
+			var awaiter = delayedTask.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsNotNull(awaiter);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNull(delayedTask.Exception);
+			Assert.AreEqual(1, executionCount);
+		}
+
+		[TestMethod]
+		public void ShouldHaveAnExceptionSet()
+		{
+			// arrange
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { throw new Exception("TEST :D"); };
+
+			// act
+			var delayedTask = DelayedTask.Run(action, delay);
+
+			var awaiter = delayedTask.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNotNull(delayedTask.Exception);
+		}
+
+		[TestMethod]
+		public void ShouldUseExceptionHandler()
+		{
+			// arrange
+			string exceptionText = null;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { throw new Exception("TEST :D"); };
+			var exceptionHandler = (Exception ex) =>
+			{
+				exceptionText = ex.Message;
+			};
+
+			// act
+			var delayedTask = DelayedTask.Run(action, delay)
+				.WithExceptionHandler(exceptionHandler);
+
+			var awaiter = delayedTask.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.IsNotNull(delayedTask.Exception);
+			Assert.AreEqual("TEST :D", exceptionText);
+		}
+
+		[TestMethod]
+		public async Task ShouldReturnNormalTask()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var action = () => { executionCount++; };
+			var delayedTask = DelayedTask.Create(action, delay);
+
+			// act
+			delayedTask.Reset();
+			var task = delayedTask.Task;
+			await task;
+
+			// assert
+			Assert.IsNotNull(delayedTask);
+			Assert.IsNotNull(task);
+			Assert.IsInstanceOfType(task, typeof(Task));
+			Assert.IsFalse(delayedTask.IsRunning);
+			Assert.IsFalse(delayedTask.IsWaitingToRun);
+			Assert.AreEqual(1, executionCount);
+			Assert.AreEqual(TaskStatus.RanToCompletion, task.Status);
+		}
+	}
+}

UnitTests/Common/Utilities/DelayedTaskWithResultTests.cs

@@ -0,0 +1,134 @@
+using System;
+using System.Diagnostics;
+using System.Threading;
+using System.Threading.Tasks;
+using AMWD.Common.Utilities;
+using Microsoft.VisualStudio.TestTools.UnitTesting;
+
+namespace UnitTests.Common.Utilities
+{
+	[TestClass]
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	public class DelayedTaskWithResultTests
+	{
+		[TestMethod]
+		public void ShouldCreateNewDelayedTaskNotStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var function = () => { executionCount++; return new[] { 42, 21 }; };
+
+			// act
+			var cts = new CancellationTokenSource(delay.Add(TimeSpan.FromSeconds(1)));
+			var delayedTaskWithResult = DelayedTask.Create(function, delay);
+			SpinWait.SpinUntil(() => executionCount > 0 || cts.IsCancellationRequested);
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.AreEqual(delay, delayedTaskWithResult.Delay);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNull(delayedTaskWithResult.Exception);
+			Assert.AreEqual(0, executionCount);
+		}
+
+		[TestMethod]
+		public async Task ShouldCreateNewDelayedTaskStarting()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var function = () => { executionCount++; return new[] { 42, 21 }; };
+
+			// act
+			var delayedTaskWithResult = DelayedTask.Run(function, delay);
+			int[] result = await delayedTaskWithResult;
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.AreEqual(delay, delayedTaskWithResult.Delay);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNull(delayedTaskWithResult.Exception);
+			Assert.AreEqual(1, executionCount);
+			CollectionAssert.AreEqual(new[] { 42, 21 }, result);
+		}
+
+		[TestMethod]
+		public void ShouldHaveAnExceptionSet()
+		{
+			// arrange
+			var delay = TimeSpan.FromMilliseconds(100);
+#pragma warning disable CS0162 // Unreachable Code detected.
+			var function = () => { throw new Exception("TEST :D"); return new[] { 42, 21 }; };
+#pragma warning restore CS0162 // Unreachable Code detected
+
+			// act
+			var delayedTaskWithResult = DelayedTask.Run(function, delay);
+
+			var awaiter = delayedTaskWithResult.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNotNull(delayedTaskWithResult.Exception);
+		}
+
+		[TestMethod]
+		public void ShouldUseExceptionHandler()
+		{
+			// arrange
+			string exceptionText = null;
+			var delay = TimeSpan.FromMilliseconds(100);
+#pragma warning disable CS0162 // Unreachable Code detected.
+			var function = () => { throw new Exception("TEST :D"); return new[] { 42, 21 }; };
+#pragma warning restore CS0162 // Unreachable Code detected
+			var exceptionHandler = (Exception ex) =>
+			{
+				exceptionText = ex.Message;
+			};
+
+			// act
+			var delayedTaskWithResult = DelayedTask.Run(function, delay)
+				.WithExceptionHandler(exceptionHandler);
+
+			var awaiter = delayedTaskWithResult.GetAwaiter();
+			SpinWait.SpinUntil(() => awaiter.IsCompleted);
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.IsNotNull(delayedTaskWithResult.Exception);
+			Assert.AreEqual("TEST :D", exceptionText);
+		}
+
+		[TestMethod]
+		public async Task ShouldReturnNormalTask()
+		{
+			// arrange
+			int executionCount = 0;
+			var delay = TimeSpan.FromMilliseconds(100);
+			var function = () => { executionCount++; return new[] { 42, 21 }; };
+			var delayedTaskWithResult = DelayedTask.Create(function, delay);
+
+			// act
+			delayedTaskWithResult.Reset();
+			var task = delayedTaskWithResult.Task;
+			int[] result = await task;
+
+			// assert
+			Assert.IsNotNull(delayedTaskWithResult);
+			Assert.IsNotNull(task);
+			Assert.IsInstanceOfType(task, typeof(Task));
+			Assert.IsFalse(delayedTaskWithResult.IsRunning);
+			Assert.IsFalse(delayedTaskWithResult.IsWaitingToRun);
+			Assert.AreEqual(1, executionCount);
+			Assert.AreEqual(TaskStatus.RanToCompletion, task.Status);
+			CollectionAssert.AreEqual(new int[] { 42, 21 }, result);
+		}
+	}
+}

UnitTests/Common/Utils/CryptographyHelperSaltMock.cs

@@ -0,0 +1,27 @@
+using System;
+using System.Security.Cryptography;
+using ReflectionMagic;
+
+namespace UnitTests.Common.Utils
+{
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	internal class CryptographyHelperSaltMock : IDisposable
+	{
+		private readonly int saltLength;
+
+		private CryptographyHelperSaltMock(int saltLength)
+		{
+			this.saltLength = typeof(CryptographyHelper).AsDynamicType().saltLength;
+			SetSaltLength(saltLength);
+		}
+
+		public static IDisposable Create(int saltLength)
+			=> new CryptographyHelperSaltMock(saltLength);
+
+		public void Dispose()
+			=> SetSaltLength(saltLength);
+
+		private static void SetSaltLength(int length)
+			=> typeof(CryptographyHelper).AsDynamicType().saltLength = length;
+	}
+}

UnitTests/Common/Utils/CustomMultipleAttribute.cs

@@ -0,0 +1,16 @@
+using System;
+
+namespace UnitTests.Common.Utils
+{
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	[AttributeUsage(AttributeTargets.All, AllowMultiple = true)]
+	internal class CustomMultipleAttribute : Attribute
+	{
+		public CustomMultipleAttribute(string name)
+		{
+			Name = name;
+		}
+
+		public string Name { get; set; }
+	}
+}

UnitTests/Common/Utils/JsonTestClass.cs

@@ -0,0 +1,50 @@
+using System;
+
+namespace UnitTests.Common.Utils
+{
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	internal class JsonTestClass
+	{
+		public string StringValue { get; set; } = "Hello World!";
+
+		public bool IsBoolTrue { get; set; } = true;
+
+		public float FloatValue { get; set; } = 12.34f;
+
+		public double DoubleValue { get; set; } = 21.42;
+
+		public decimal DecimalValue { get; set; } = 42.21m;
+
+		public DateTime LocalTimestamp { get; set; } = new(2021, 11, 16, 20, 15, 34, DateTimeKind.Local);
+
+		public DateTime UtcTimestamp { get; set; } = new(2021, 11, 16, 20, 15, 34, DateTimeKind.Utc);
+
+		public JsonTestSubClass Object { get; set; } = new();
+	}
+
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	internal class JsonTestSubClass
+	{
+		public int IntegerValue { get; set; } = 42;
+
+		public string StringValue { get; set; } = "Foo-Bar";
+	}
+
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	internal class JsonErrorClass
+	{
+		private int? number;
+
+		public int Number
+		{
+			get
+			{
+				if (number.HasValue)
+					return number.Value;
+
+				throw new Exception("Null value");
+			}
+			set { number = value; }
+		}
+	}
+}

UnitTests/Common/Utils/TimeZoneInfoLocalMock.cs

@@ -0,0 +1,26 @@
+using System;
+using ReflectionMagic;
+
+namespace UnitTests.Common.Utils
+{
+	[System.Diagnostics.CodeAnalysis.ExcludeFromCodeCoverage]
+	internal class TimeZoneInfoLocalMock : IDisposable
+	{
+		private readonly TimeZoneInfo localTimeZoneInfo;
+
+		private TimeZoneInfoLocalMock(TimeZoneInfo timeZoneInfo)
+		{
+			localTimeZoneInfo = TimeZoneInfo.Local;
+			SetLocalTimeZone(timeZoneInfo);
+		}
+
+		public static IDisposable Create(TimeZoneInfo mockTimeZoneInfo)
+			=> new TimeZoneInfoLocalMock(mockTimeZoneInfo);
+
+		public void Dispose()
+			=> SetLocalTimeZone(localTimeZoneInfo);
+
+		private static void SetLocalTimeZone(TimeZoneInfo timeZoneInfo)
+			=> typeof(TimeZoneInfo).AsDynamicType().s_cachedData._localTimeZone = timeZoneInfo;
+	}
+}