Fixing integer overflow issue in RTS metrics (Azure#6539)

src/WebJobs.Script.WebHost/Scale/TableEntityConverter.cs

@@ -91,7 +91,9 @@ public static bool TryGetEntityProperty(JProperty property, out EntityProperty e
                     entityProperty = new EntityProperty(value.ToObject<Guid>());
                     return true;
                 case JTokenType.Integer:
-                    entityProperty = new EntityProperty(value.ToObject<int>());
+                    // to handle both ints and longs, we normalize integer values
+                    // to type long
+                    entityProperty = new EntityProperty(value.ToObject<long>());
                     return true;
                 case JTokenType.String:
                     entityProperty = new EntityProperty(value.ToObject<string>());

src/WebJobs.Script.WebHost/Scale/TableStorageScaleMetricsRepository.cs

@@ -22,7 +22,7 @@ namespace Microsoft.Azure.WebJobs.Script.WebHost
     public class TableStorageScaleMetricsRepository : IScaleMetricsRepository
     {
         internal const string TableNamePrefix = "AzureFunctionsScaleMetrics";
-        private const string MonitorIdPropertyName = "MonitorId";
+        internal const string MonitorIdPropertyName = "MonitorId";
         private const string SampleTimestampPropertyName = "SampleTimestamp";
         private const int MetricsPurgeDelaySeconds = 30;
         private const int DefaultTableCreationRetries = 3;
@@ -272,7 +272,7 @@ internal static TableOperation CreateMetricsInsertOperation(ScaleMetrics metrics
 
             // Use an inverted ticks rowkey to order the table in descending order, allowing us to easily
             // query for latest logs. Adding a guid as part of the key to ensure uniqueness.
-            string rowKey = string.Format("{0:D19}-{1}", DateTime.MaxValue.Ticks - now.Value.Ticks, Guid.NewGuid());
+            string rowKey = GetRowKey(now.Value);
 
             var entity = TableEntityConverter.ToEntity(metrics, hostId, rowKey, metrics.Timestamp);
             entity.Properties.Add(MonitorIdPropertyName, EntityProperty.GeneratePropertyForString(descriptor.Id));
@@ -285,6 +285,11 @@ internal static TableOperation CreateMetricsInsertOperation(ScaleMetrics metrics
             return TableOperation.Insert(entity);
         }
 
+        internal static string GetRowKey(DateTime now)
+        {
+            return string.Format("{0:D19}-{1}", DateTime.MaxValue.Ticks - now.Ticks, Guid.NewGuid());
+        }
+
         internal async Task<IEnumerable<DynamicTableEntity>> ExecuteQuerySafeAsync(CloudTable metricsTable, TableQuery query)
         {
             try

test/WebJobs.Script.Tests.Integration/Scale/TableStorageScaleMetricsRepositoryTests.cs

@@ -135,6 +135,78 @@ public async Task WriteMetricsAsync_PersistsMetrics()
             Assert.Equal(0, result.Count);
         }
 
+        [Fact]
+        public async Task ReadWriteMetrics_IntegerConversion_HandlesLongs()
+        {
+            var monitor1 = new TestScaleMonitor1();
+            var monitors = new IScaleMonitor[] { monitor1 };
+
+            // first write a couple entities manually to the table to simulate
+            // the change in entity property type (int -> long)
+            // this shows that the table can have entities of both formats with
+            // no versioning issues
+
+            // add an entity with Count property of type int
+            var entity = new DynamicTableEntity
+            {
+                RowKey = TableStorageScaleMetricsRepository.GetRowKey(DateTime.UtcNow),
+                PartitionKey = TestHostId,
+                Properties = new Dictionary<string, EntityProperty>()
+            };
+            var expectedIntCountValue = int.MaxValue;
+            entity.Properties.Add("Timestamp", new EntityProperty(DateTime.UtcNow));
+            entity.Properties.Add("Count", new EntityProperty(expectedIntCountValue));
+            entity.Properties.Add(TableStorageScaleMetricsRepository.MonitorIdPropertyName, EntityProperty.GeneratePropertyForString(monitor1.Descriptor.Id));
+            var batch = new TableBatchOperation();
+            batch.Add(TableOperation.Insert(entity));
+
+            // add an entity with Count property of type long
+            entity = new DynamicTableEntity
+            {
+                RowKey = TableStorageScaleMetricsRepository.GetRowKey(DateTime.UtcNow),
+                PartitionKey = TestHostId,
+                Properties = new Dictionary<string, EntityProperty>()
+            };
+            var expectedLongCountValue = long.MaxValue;
+            entity.Properties.Add("Timestamp", new EntityProperty(DateTime.UtcNow));
+            entity.Properties.Add("Count", new EntityProperty(expectedLongCountValue));
+            entity.Properties.Add(TableStorageScaleMetricsRepository.MonitorIdPropertyName, EntityProperty.GeneratePropertyForString(monitor1.Descriptor.Id));
+            batch.Add(TableOperation.Insert(entity));
+
+            await _repository.ExecuteBatchSafeAsync(batch);
+
+            // push a long max value through serialization
+            var metricsMap = new Dictionary<IScaleMonitor, ScaleMetrics>();
+            metricsMap.Add(monitor1, new TestScaleMetrics1 { Count = long.MaxValue });
+            await _repository.WriteMetricsAsync(metricsMap);
+
+            // add one more
+            metricsMap = new Dictionary<IScaleMonitor, ScaleMetrics>();
+            metricsMap.Add(monitor1, new TestScaleMetrics1 { Count = 12345 });
+            await _repository.WriteMetricsAsync(metricsMap);
+
+            // read the metrics back
+            var result = await _repository.ReadMetricsAsync(monitors);
+            Assert.Equal(1, result.Count);
+            var monitorMetricsList = result[monitor1];
+            Assert.Equal(4, monitorMetricsList.Count);
+
+            // verify the explicitly written int record was read correctly
+            var currSample = (TestScaleMetrics1)monitorMetricsList[0];
+            Assert.Equal(expectedIntCountValue, currSample.Count);
+
+            // verify the explicitly written long record was read correctly
+            currSample = (TestScaleMetrics1)monitorMetricsList[1];
+            Assert.Equal(expectedLongCountValue, currSample.Count);
+
+            // verify the final roundtripped values
+            currSample = (TestScaleMetrics1)monitorMetricsList[2];
+            Assert.Equal(long.MaxValue, currSample.Count);
+
+            currSample = (TestScaleMetrics1)monitorMetricsList[3];
+            Assert.Equal(12345, currSample.Count);
+        }
+
         [Fact]
         public async Task ReadMetricsAsync_FiltersExpiredMetrics()
         {

test/WebJobs.Script.Tests.Shared/TestScaleMonitor.cs

@@ -61,7 +61,7 @@ public class TestScaleMonitor1 : TestScaleMonitor<TestScaleMetrics1>
 
     public class TestScaleMetrics1 : ScaleMetrics
     {
-        public int Count { get; set; }
+        public long Count { get; set; }
     }
 
     public class TestScaleMonitor2 : TestScaleMonitor<TestScaleMetrics2>