fixed string format

sdk/monitor/Azure.Monitor.Query/src/MetricsClient.cs

@@ -150,8 +150,12 @@ private async Task<Response<MetricsQueryResourcesResult>> ExecuteBatchAsync(IEnu
             {
                 if (options.TimeRange != null)
                 {
-                    startTime = options.TimeRange.Value.Start.ToString();
-                    endTime = options.TimeRange.Value.End.ToString();
+                    DateTimeOffset? startTimeDto = options.TimeRange.Value.Start;
+                    DateTimeOffset? endTimeDto = options.TimeRange.Value.End;
+                    TimeSpan duration = options.TimeRange.Value.Duration;
+
+                    startTime = startTimeDto.ToIsoString() ?? endTimeDto?.Subtract(duration).ToIsoString();
+                    endTime = endTimeDto.ToIsoString() ?? startTimeDto?.Add(duration).ToIsoString();
                 }
                 aggregations = MetricsClientExtensions.CommaJoin(options.Aggregations);
                 top = options.Size;

sdk/monitor/Azure.Monitor.Query/src/MetricsClientExtensions.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using System.Text;
 using Azure.Monitor.Query.Models;
@@ -51,5 +52,21 @@ internal static IList<string> CommaSplit(string value) =>
                 new List<string>() :
                 // TODO: #10600 - Verify we don't need to worry about escaping
                 new List<string>(value.Split(','));
+
+        internal static string ToIsoString(this DateTimeOffset value)
+        {
+            if (value.Offset == TimeSpan.Zero)
+            {
+                // Some Azure service required 0-offset dates to be formatted without the
+                // -00:00 part
+                const string roundtripZFormat = "yyyy-MM-ddTHH:mm:ss.fffffffZ";
+                return value.ToString(roundtripZFormat, CultureInfo.InvariantCulture);
+            }
+
+            return value.ToString("O", CultureInfo.InvariantCulture);
+        }
+
+        internal static string ToIsoString(this DateTimeOffset? value)
+            => value != null ? value.Value.ToIsoString() : null;
     }
 }

sdk/monitor/Azure.Monitor.Query/src/QueryTimeRange.cs

@@ -2,7 +2,6 @@
 // Licensed under the MIT License.
 
 using System;
-using System.Globalization;
 using System.Xml;
 using Azure.Core;
 
@@ -105,21 +104,8 @@ public override string ToString()
 
         internal string ToIsoString()
         {
-            string ToString(DateTimeOffset value)
-            {
-                if (value.Offset == TimeSpan.Zero)
-                {
-                    // Some Azure service required 0-offset dates to be formatted without the
-                    // -00:00 part
-                    const string roundtripZFormat = "yyyy-MM-ddTHH:mm:ss.fffffffZ";
-                    return value.ToString(roundtripZFormat, CultureInfo.InvariantCulture);
-                }
-
-                return value.ToString("O", CultureInfo.InvariantCulture);
-            }
-
-            var startTime = Start != null ? ToString(Start.Value) : null;
-            var endTime = End != null ? ToString(End.Value) : null;
+            var startTime = Start.ToIsoString();
+            var endTime = End.ToIsoString();
             var duration = XmlConvert.ToString(Duration);
 
             switch (startTime, endTime, duration)

sdk/monitor/Azure.Monitor.Query/tests/MetricsQueryClientLiveTests.cs

@@ -368,5 +368,37 @@ public void MetricsQueryResourcesInvalid()
                 metricNames: new List<string> { "Ingress" },
                 metricNamespace: "Microsoft.Storage/storageAccounts"));
         }
+
+        [RecordedTest]
+        public async Task MetricsQueryMetricsStartEnd()
+        {
+            var client = CreateMetricsClient();
+            var queryOptions = new MetricsQueryResourcesOptions
+            {
+                TimeRange = new QueryTimeRange(DateTimeOffset.MinValue, DateTimeOffset.MaxValue)
+            };
+            var resourceId = TestEnvironment.StorageAccountId;
+
+            Response<MetricsQueryResourcesResult> metricsResultsResponse = await client.QueryResourcesAsync(
+                resourceIds: new List<ResourceIdentifier> { new ResourceIdentifier(resourceId) },
+                metricNames: new List<string> { "Ingress" },
+                metricNamespace: "Microsoft.Storage/storageAccounts",
+                options: queryOptions).ConfigureAwait(false);
+
+            MetricsQueryResourcesResult metricsQueryResults = metricsResultsResponse.Value;
+            Assert.AreEqual(1, metricsQueryResults.Values.Count);
+            Assert.AreEqual(TestEnvironment.StorageAccountId + "/providers/Microsoft.Insights/metrics/Ingress", metricsQueryResults.Values[0].Metrics[0].Id);
+            Assert.AreEqual("Microsoft.Storage/storageAccounts", metricsQueryResults.Values[0].Namespace);
+            for (int i = 0; i < metricsQueryResults.Values.Count; i++)
+            {
+                foreach (MetricResult value in metricsQueryResults.Values[i].Metrics)
+                {
+                    for (int j = 0; j < value.TimeSeries.Count; j++)
+                    {
+                        Assert.GreaterOrEqual(value.TimeSeries[j].Values[i].Total, 0);
+                    }
+                }
+            }
+        }
     }
 }