Refactor for DataValue

src/OpenTelemetry/Metrics/DataPoint/DataPoint.cs

@@ -23,26 +23,27 @@ namespace OpenTelemetry.Metrics
     {
         private static readonly KeyValuePair<string, object>[] EmptyTag = new KeyValuePair<string, object>[0];
 
-        private readonly Type valueType;
-        private readonly long longValue;
-        private readonly double doubleValue;
+        private readonly IDataValue value;
 
         internal DataPoint(DateTimeOffset timestamp, long value, KeyValuePair<string, object>[] tags)
         {
             this.Timestamp = timestamp;
             this.Tags = tags;
-            this.valueType = typeof(long);
-            this.longValue = value;
-            this.doubleValue = 0;
+            this.value = new DataValue<long>(value);
         }
 
         internal DataPoint(DateTimeOffset timestamp, double value, KeyValuePair<string, object>[] tags)
         {
             this.Timestamp = timestamp;
             this.Tags = tags;
-            this.valueType = typeof(double);
-            this.longValue = 0;
-            this.doubleValue = value;
+            this.value = new DataValue<double>(value);
+        }
+
+        internal DataPoint(DateTimeOffset timestamp, IDataValue value, KeyValuePair<string, object>[] tags)
+        {
+            this.Timestamp = timestamp;
+            this.Tags = tags;
+            this.value = value;
         }
 
         internal DataPoint(DateTimeOffset timestamp, long value)
@@ -55,52 +56,15 @@ internal DataPoint(DateTimeOffset timestamp, double value)
         {
         }
 
-        public DateTimeOffset Timestamp { get; }
-
-        public readonly KeyValuePair<string, object>[] Tags { get; }
-
-        public object Value
+        internal DataPoint(DateTimeOffset timestamp, IDataValue value)
+            : this(timestamp, value, DataPoint.EmptyTag)
         {
-            get
-            {
-                if (this.valueType == typeof(long))
-                {
-                    return this.longValue;
-                }
-                else if (this.valueType == typeof(double))
-                {
-                    return this.doubleValue;
-                }
-                else
-                {
-                    throw new Exception("Unsupported Type");
-                }
-            }
         }
 
-        internal static DataPoint CreateDataPoint<T>(DateTimeOffset timestamp, T value, KeyValuePair<string, object>[] tags)
-        {
-            DataPoint dp;
+        public DateTimeOffset Timestamp { get; }
 
-            if (typeof(T) == typeof(int))
-            {
-                // Promoted to Long
-                dp = new DataPoint(timestamp, (int)(object)value, tags);
-            }
-            else if (typeof(T) == typeof(long))
-            {
-                dp = new DataPoint(timestamp, (long)(object)value, tags);
-            }
-            else if (typeof(T) == typeof(double))
-            {
-                dp = new DataPoint(timestamp, (double)(object)value, tags);
-            }
-            else
-            {
-                throw new Exception("Unsupported Type");
-            }
+        public readonly KeyValuePair<string, object>[] Tags { get; }
 
-            return dp;
-        }
+        public object Value => this.value.Value;
     }
 }

src/OpenTelemetry/Metrics/DataPoint/DataPoint{T}.cs

@@ -24,9 +24,16 @@ namespace OpenTelemetry.Metrics
     {
         private static readonly KeyValuePair<string, object>[] EmptyTag = new KeyValuePair<string, object>[0];
 
-        private readonly T value;
+        private readonly IDataValue value;
 
         internal DataPoint(DateTimeOffset timestamp, T value, KeyValuePair<string, object>[] tags)
+        {
+            this.Timestamp = timestamp;
+            this.Tags = tags;
+            this.value = new DataValue<T>(value);
+        }
+
+        internal DataPoint(DateTimeOffset timestamp, IDataValue value, KeyValuePair<string, object>[] tags)
         {
             this.Timestamp = timestamp;
             this.Tags = tags;
@@ -38,10 +45,15 @@ internal DataPoint(DateTimeOffset timestamp, T value)
         {
         }
 
+        internal DataPoint(DateTimeOffset timestamp, IDataValue value)
+            : this(timestamp, value, DataPoint<T>.EmptyTag)
+        {
+        }
+
         public DateTimeOffset Timestamp { get; }
 
         public readonly KeyValuePair<string, object>[] Tags { get; }
 
-        public object Value => (object)this.value;
+        public object Value => this.value.Value;
     }
 }

src/OpenTelemetry/Metrics/DataPoint/DataValue.cs

@@ -0,0 +1,48 @@
+// <copyright file="DataValue.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// </copyright>
+
+using System;
+
+namespace OpenTelemetry.Metrics
+{
+    public readonly struct DataValue : IDataValue
+    {
+        private readonly IDataValue value;
+
+        internal DataValue(int value)
+        {
+            // Promote to long
+            this.value = new DataValue<long>(value);
+        }
+
+        internal DataValue(long value)
+        {
+            this.value = new DataValue<long>(value);
+        }
+
+        internal DataValue(double value)
+        {
+            this.value = new DataValue<double>(value);
+        }
+
+        internal DataValue(IDataValue value)
+        {
+            this.value = value;
+        }
+
+        public object Value => this.value.Value;
+    }
+}

src/OpenTelemetry/Metrics/DataPoint/DataValue{T}.cs

@@ -0,0 +1,31 @@
+// <copyright file="DataValue{T}.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// </copyright>
+
+namespace OpenTelemetry.Metrics
+{
+    internal readonly struct DataValue<T> : IDataValue
+        where T : struct
+    {
+        private readonly T value;
+
+        internal DataValue(T value)
+        {
+            this.value = value;
+        }
+
+        public object Value => (object)this.value;
+    }
+}

src/OpenTelemetry/Metrics/DataPoint/Exemplar.cs

@@ -24,19 +24,15 @@ namespace OpenTelemetry.Metrics
         private static readonly KeyValuePair<string, object>[] EmptyTag = new KeyValuePair<string, object>[0];
         private static readonly byte[] EmptyId = new byte[0];
 
-        private readonly Type valueType;
-        private readonly long longValue;
-        private readonly double doubleValue;
+        private readonly IDataValue value;
 
         internal Exemplar(DateTimeOffset timestamp, long value, byte[] spanId, byte[] traceId, KeyValuePair<string, object>[] filteredTags)
         {
             this.Timestamp = timestamp;
             this.FilteredTags = filteredTags;
             this.SpanId = spanId;
             this.TraceId = traceId;
-            this.valueType = typeof(long);
-            this.longValue = value;
-            this.doubleValue = 0;
+            this.value = new DataValue<long>(value);
         }
 
         internal Exemplar(DateTimeOffset timestamp, double value, byte[] spanId, byte[] traceId, KeyValuePair<string, object>[] filteredTags)
@@ -45,9 +41,16 @@ internal Exemplar(DateTimeOffset timestamp, double value, byte[] spanId, byte[]
             this.FilteredTags = filteredTags;
             this.SpanId = spanId;
             this.TraceId = traceId;
-            this.valueType = typeof(double);
-            this.longValue = 0;
-            this.doubleValue = value;
+            this.value = new DataValue<double>(value);
+        }
+
+        internal Exemplar(DateTimeOffset timestamp, IDataValue value, byte[] spanId, byte[] traceId, KeyValuePair<string, object>[] filteredTags)
+        {
+            this.Timestamp = timestamp;
+            this.FilteredTags = filteredTags;
+            this.SpanId = spanId;
+            this.TraceId = traceId;
+            this.value = value;
         }
 
         internal Exemplar(DateTimeOffset timestamp, long value)
@@ -60,6 +63,11 @@ internal Exemplar(DateTimeOffset timestamp, double value)
         {
         }
 
+        internal Exemplar(DateTimeOffset timestamp, IDataValue value)
+            : this(timestamp, value, Exemplar.EmptyId, Exemplar.EmptyId, Exemplar.EmptyTag)
+        {
+        }
+
         public DateTimeOffset Timestamp { get; }
 
         public readonly KeyValuePair<string, object>[] FilteredTags { get; }
@@ -68,48 +76,6 @@ internal Exemplar(DateTimeOffset timestamp, double value)
 
         public readonly byte[] TraceId { get; }
 
-        public object Value
-        {
-            get
-            {
-                if (this.valueType == typeof(long))
-                {
-                    return this.longValue;
-                }
-                else if (this.valueType == typeof(double))
-                {
-                    return this.doubleValue;
-                }
-                else
-                {
-                    throw new Exception("Unsupported Type");
-                }
-            }
-        }
-
-        internal static Exemplar CreateExemplar<T>(DateTimeOffset timestamp, T value, byte[] spanId, byte[] traceId, KeyValuePair<string, object>[] filteredTags)
-        {
-            Exemplar dp;
-
-            if (typeof(T) == typeof(int))
-            {
-                // Promoted to Long
-                dp = new Exemplar(timestamp, (int)(object)value, spanId, traceId, filteredTags);
-            }
-            else if (typeof(T) == typeof(long))
-            {
-                dp = new Exemplar(timestamp, (long)(object)value, spanId, traceId, filteredTags);
-            }
-            else if (typeof(T) == typeof(double))
-            {
-                dp = new Exemplar(timestamp, (double)(object)value, spanId, traceId, filteredTags);
-            }
-            else
-            {
-                throw new Exception("Unsupported Type");
-            }
-
-            return dp;
-        }
+        public object Value => this.value.Value;
     }
 }

src/OpenTelemetry/Metrics/DataPoint/Exemplar{T}.cs

@@ -25,9 +25,18 @@ namespace OpenTelemetry.Metrics
         private static readonly KeyValuePair<string, object>[] EmptyTag = new KeyValuePair<string, object>[0];
         private static readonly byte[] EmptyId = new byte[0];
 
-        private readonly T value;
+        private readonly IDataValue value;
 
         internal Exemplar(DateTimeOffset timestamp, T value, byte[] spanId, byte[] traceId, KeyValuePair<string, object>[] filteredTags)
+        {
+            this.Timestamp = timestamp;
+            this.FilteredTags = filteredTags;
+            this.SpanId = spanId;
+            this.TraceId = traceId;
+            this.value = new DataValue<T>(value);
+        }
+
+        internal Exemplar(DateTimeOffset timestamp, IDataValue value, byte[] spanId, byte[] traceId, KeyValuePair<string, object>[] filteredTags)
         {
             this.Timestamp = timestamp;
             this.FilteredTags = filteredTags;
@@ -41,6 +50,11 @@ internal Exemplar(DateTimeOffset timestamp, T value)
         {
         }
 
+        internal Exemplar(DateTimeOffset timestamp, IDataValue value)
+            : this(timestamp, value, Exemplar<T>.EmptyId, Exemplar<T>.EmptyId, Exemplar<T>.EmptyTag)
+        {
+        }
+
         public DateTimeOffset Timestamp { get; }
 
         public readonly KeyValuePair<string, object>[] FilteredTags { get; }
@@ -49,6 +63,6 @@ internal Exemplar(DateTimeOffset timestamp, T value)
 
         public readonly byte[] TraceId { get; }
 
-        public object Value => (object)this.value;
+        public object Value => this.value.Value;
     }
 }

src/OpenTelemetry/Metrics/DataPoint/IDataPoint.cs

@@ -19,12 +19,10 @@
 
 namespace OpenTelemetry.Metrics
 {
-    internal interface IDataPoint
+    public interface IDataPoint : IDataValue
     {
         DateTimeOffset Timestamp { get; }
 
         KeyValuePair<string, object>[] Tags { get; }
-
-        object Value { get; }
     }
 }

src/OpenTelemetry/Metrics/DataPoint/IDataValue.cs

@@ -0,0 +1,23 @@
+// <copyright file="IDataValue.cs" company="OpenTelemetry Authors">
+// Copyright The OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+// </copyright>
+
+namespace OpenTelemetry.Metrics
+{
+    public interface IDataValue
+    {
+        object Value { get; }
+    }
+}