Fixes #1300

Author: Andrew Ochsner

src/Elasticsearch.Net/Extensions/StringExtensions.cs

@@ -1,4 +1,5 @@
-using System.Collections.Specialized;
+using System;
+using System.Collections.Specialized;
 
 namespace Elasticsearch.Net
 {
@@ -25,6 +26,36 @@ internal static NameValueCollection ToNameValueCollection(this string queryStrin
 
 			return queryParameters;
 		}
-		
+		internal static TimeSpan? ToTimeSpan(this string s)
+		{
+			if (s.IsNullOrEmpty())
+				return null;
+			long wholeNumber;
+			if (long.TryParse(s, out wholeNumber))
+			{
+				return TimeSpan.FromMilliseconds(wholeNumber);
+			}
+			double decimalNumber;
+			var unit = s.Substring(s.Length - 1);
+			if (s.Length <= 1 || !double.TryParse(s.Substring(0, s.Length - 1), out decimalNumber))
+			{
+				return null;
+			}
+			switch (unit)
+			{
+				case "s":
+					return TimeSpan.FromSeconds(decimalNumber);
+				case "m":
+					return TimeSpan.FromMinutes(decimalNumber);
+				case "h":
+					return TimeSpan.FromHours(decimalNumber);
+				case "d":
+					return TimeSpan.FromDays(decimalNumber);
+				case "w":
+					return TimeSpan.FromDays(decimalNumber * 7);
+				default:
+					return null;
+			}
+		}
 	}
 }

src/Tests/Nest.Tests.Unit/Extensions/StringExtensionsTests.cs

@@ -3,35 +3,76 @@
 
 namespace Nest.Tests.Unit.Extensions
 {
-    [TestFixture]
-    public class StringExtensionsTests
-    {
-        [Test]
-        public void CanConvertQueryStringToNameValueCollectionWithQuestionMark()
-        {
-            // Arrange
-            var queryString = "?test1=one&test2=two";
-
-            // Act
-            var queryCollection = queryString.ToNameValueCollection();
-
-            // Assert
-            Assert.IsTrue(queryCollection["test1"] == "one");
-            Assert.IsTrue(queryCollection["test2"] == "two");
-        }
-
-        [Test]
-        public void CanConvertQueryStringToNameValueCollectionWithoutQuestionMark()
-        {
-            // Arrange
-            var queryString = "test1=testone&test2=testtwo";
-
-            // Act
-            var queryCollection = queryString.ToNameValueCollection();
-
-            // Assert
-            Assert.IsTrue(queryCollection["test1"] == "testone");
-            Assert.IsTrue(queryCollection["test2"] == "testtwo");
-        }
-    }
+	[TestFixture]
+	public class StringExtensionsTests
+	{
+		[Test]
+		public void CanConvertQueryStringToNameValueCollectionWithQuestionMark()
+		{
+			// Arrange
+			var queryString = "?test1=one&test2=two";
+
+			// Act
+			var queryCollection = queryString.ToNameValueCollection();
+
+			// Assert
+			Assert.IsTrue(queryCollection["test1"] == "one");
+			Assert.IsTrue(queryCollection["test2"] == "two");
+		}
+
+		[Test]
+		public void CanConvertQueryStringToNameValueCollectionWithoutQuestionMark()
+		{
+			// Arrange
+			var queryString = "test1=testone&test2=testtwo";
+
+			// Act
+			var queryCollection = queryString.ToNameValueCollection();
+
+			// Assert
+			Assert.IsTrue(queryCollection["test1"] == "testone");
+			Assert.IsTrue(queryCollection["test2"] == "testtwo");
+		}
+
+		private const int s = 1000;
+		private const int m = 60 * s;
+		private const int h = 60 * m;
+		private const int d = 24 * h;
+		private const int w = 7 * d;
+
+		/// <summary />
+		[TestCase("0s", 0)]
+		[TestCase("1s", 1 * s)]
+		[TestCase("-1s", -1 * s)]
+		[TestCase("1.5s", 1.5 * s)]
+		[TestCase("90s", 90 * s)]
+		[TestCase("1m", 1 * m)]
+		[TestCase("1h", 1 * h)]
+		[TestCase("1d", 1 * d)]
+		[TestCase("1w", 1 * w)]
+		[TestCase("0", 0)]
+		[TestCase("1", 1)]
+		public void ParseElasticSearchTimeUnit_Success(string value, double timeInMillis)
+		{
+			// act
+			Assert.That(value.ToTimeSpan().Value.TotalMilliseconds, Is.EqualTo(timeInMillis));
+		}
+
+		[TestCase(null)]
+		[TestCase("")]
+		[TestCase(" ")]
+		[TestCase("1.5")]
+		[TestCase("2s2")]
+		[TestCase("2ss")]
+		[TestCase("4m2s")]
+		[TestCase("2M")]
+		[TestCase("2y")]
+		[TestCase("s")]
+		public void ParseElasticSearchTimeUnit_Fail_ReturnsNull(string value)
+		{
+			// act
+			Assert.That(value.ToTimeSpan(), Is.Null);
+		} 
+
+	}
 }