Consider null value in carbonIntensity on EM (#575)

Issue #571

Signed-off-by: Yasumasa Suenaga <[email protected]>

src/CarbonAware.DataSources/CarbonAware.DataSources.ElectricityMaps/src/Model/HistoryCarbonIntensityData.cs

@@ -32,7 +32,7 @@ internal record CarbonIntensity
     /// Carbon Intensity value.
     /// </summary>
     [JsonPropertyName("carbonIntensity")]
-    public int Value { get; init; }
+    public int? Value { get; init; }
 
     /// <summary>
     /// Indicates the datetime of the carbon intensity
@@ -74,7 +74,7 @@ public static explicit operator EmissionsData(CarbonIntensity historyCarbonInten
     {
         return new EmissionsData
         {
-            Rating = historyCarbonIntensity.Value,
+            Rating = historyCarbonIntensity.Value ?? -1,
             Time = historyCarbonIntensity.UpdatedAt,
         };
     }

src/CarbonAware.DataSources/CarbonAware.DataSources.ElectricityMaps/test/Client/ElectricityMapsClientTests.cs

@@ -8,6 +8,7 @@
 using Moq.Protected;
 using Moq.Contrib.HttpClient;
 using System.Text.Json;
+using CarbonAware.Model;
 
 namespace CarbonAware.DataSources.ElectricityMaps.Tests;
 
@@ -299,4 +300,36 @@ private void AddHandler_RequestResponse(Predicate<HttpRequestMessage> requestPre
                 .ReturnsResponse(statusCode);
         }    
     }
+
+    [Test]
+    public async Task GetRecentCarbonIntensityHistoryAsync_DeserializesExpectedResponseWithNull()
+    {
+        AddHandler_RequestResponse(r =>
+        {
+            return r.Method == HttpMethod.Get;
+        }, System.Net.HttpStatusCode.OK, TestData.GetHistoryCarbonIntensityDataJsonStringWithNull());
+
+        var client = new ElectricityMapsClient(this.HttpClientFactory, this.Options.Object, this.Log.Object);
+
+        // Act
+        var data = await client.GetRecentCarbonIntensityHistoryAsync(TestLatitude, TestLongitude);
+        var dataPoint = data?.HistoryData.First();
+
+        // Assert
+        Assert.That(data, Is.Not.Null);
+        Assert.That(data?.Zone, Is.EqualTo(TestZone));
+        Assert.That(data?.HistoryData.Count(), Is.GreaterThan(0));
+        Assert.Multiple(() =>
+        {
+            Assert.That(dataPoint?.DateTime, Is.EqualTo(new DateTimeOffset(2099, 1, 1, 0, 0, 0, TimeSpan.Zero)));
+            Assert.That(dataPoint?.UpdatedAt, Is.EqualTo(new DateTimeOffset(2099, 1, 1, 0, 0, 0, TimeSpan.Zero)));
+            Assert.That(dataPoint?.CreatedAt, Is.EqualTo(new DateTimeOffset(2099, 1, 1, 0, 0, 0, TimeSpan.Zero)));
+            Assert.That(dataPoint?.Value, Is.Null);
+            Assert.That(((EmissionsData)dataPoint).Rating, Is.EqualTo(-1));
+            Assert.That(dataPoint?.EmissionFactorType, Is.EqualTo("lifecycle"));
+            Assert.That(dataPoint?.IsEstimated, Is.False);
+            Assert.That(dataPoint?.EstimationMethod, Is.Null);
+        });
+    }
+
 }

src/CarbonAware.DataSources/CarbonAware.DataSources.ElectricityMaps/test/Client/TestData.cs

@@ -92,4 +92,28 @@ public static string GetCurrentForecastJsonString()
 
         return json.ToString();
     }
+
+    public static string GetHistoryCarbonIntensityDataJsonStringWithNull()
+    {
+        var json = new JsonObject
+        {
+            ["zone"] = TestZoneId1,
+            ["history"] = new JsonArray
+            {
+                new JsonObject
+                {
+                    ["datetime"] = new DateTimeOffset(2099, 1, 1, 0, 0, 0, TimeSpan.Zero),
+                    ["updatedAt"] = new DateTimeOffset(2099, 1, 1, 0, 0, 0, TimeSpan.Zero),
+                    ["createdAt"] = new DateTimeOffset(2099, 1, 1, 0, 0, 0, TimeSpan.Zero),
+                    ["carbonIntensity"] = null,
+                    ["emissionFactorType"] = "lifecycle",
+                    ["isEstimated"] = false,
+                    ["estimatedMethod"] = null,
+                }
+            }
+        };
+
+        return json.ToString();
+    }
+
 }