Ensure metrics are evaluated strictly.

Metrics should not be evaluated lazily as this delays the
calculation until the data is requested.
Concretely, this means we should evaluate all intances of
`IEnumerable<T>` using `.ToList()` within the publisher's
`YieldMetrics` method.

This change updates the `PublisherComponent` implementations
where necessary.

Author: dandanlen

src/explorer/Components/Datetime/DatetimeGeneratorComponent.cs

@@ -32,7 +32,7 @@ public async IAsyncEnumerable<ExploreMetric> YieldMetrics()
                 metric: distribution
                         .Generate(SamplesToPublish)
                         .OrderBy(_ => _)
-                        .ToArray());
+                        .ToList());
         }
     }
 }

src/explorer/Components/Datetime/TimeUtilities.cs

@@ -37,16 +37,16 @@ private static object MetricBlob<T>(
             {
                 Total = total,
                 Suppressed = suppressed,
-                Counts =
-                    from row in valueCounts
-                    where row.HasValue
-                    orderby row.GroupingIndex ascending
-                    select new
+                Counts = valueCounts
+                    .Where(row => row.HasValue)
+                    .OrderBy(row => row.GroupingIndex)
+                    .Select(row => new
                     {
                         row.Value,
                         row.Count,
                         row.CountNoise,
-                    },
+                    })
+                    .ToList(),
             };
         }
 

src/explorer/Components/DistinctValuesComponent.cs

@@ -87,12 +87,12 @@ public class Result
         {
             public Result(IEnumerable<ValueWithCount<JsonElement>> distinctRows)
             {
-                DistinctRows = distinctRows;
+                DistinctRows = distinctRows.ToList();
                 ValueCounts = ValueCounts.Compute(distinctRows);
                 IsCategorical = ValueCounts.SuppressedRowRatio < SuppressedRatioThreshold;
             }
 
-            public IEnumerable<ValueWithCount<JsonElement>> DistinctRows { get; }
+            public List<ValueWithCount<JsonElement>> DistinctRows { get; }
 
             public ValueCounts ValueCounts { get; }
 

src/explorer/Components/DistributionAnalysisComponent.cs

@@ -57,7 +57,8 @@ ks is null
                         }
                         .Where(gm => !(gm is null) && double.IsFinite(gm.PValue)),
                     };
-                }));
+                })
+                .ToList());
         }
 
         protected override async Task<GoodnessOfFitCollection?> Explore()

src/explorer/Components/DistributionPublishers/NumericSampleGenerator.cs

@@ -47,7 +47,7 @@ public async IAsyncEnumerable<ExploreMetric> YieldMetrics()
                         .Generate(SamplesToPublish)
                         .Select(s => Context.ColumnInfo.Type == Diffix.DValueType.Real ? s : Convert.ToInt64(s))
                         .OrderBy(_ => _)
-                        .ToArray());
+                        .ToList());
         }
     }
 }

src/explorer/Components/HistogramSelectorComponent.cs

@@ -35,7 +35,8 @@ public async IAsyncEnumerable<ExploreMetric> YieldMetrics()
                 b.LowerBound,
                 b.Count,
                 b.CountNoise,
-            }));
+            })
+            .ToList());
             yield return new UntypedMetric("histogram.suppressed_count", result.ValueCounts.SuppressedCount);
             yield return new UntypedMetric("histogram.suppressed_ratio", result.ValueCounts.SuppressedCountRatio);
             yield return new UntypedMetric("histogram.value_counts", result.ValueCounts);

src/explorer/Components/TextLengthComponent.cs

@@ -26,7 +26,8 @@ public async IAsyncEnumerable<ExploreMetric> YieldMetrics()
                 result.DistinctRows
                     .Where(r => r.HasValue)
                     .OrderBy(r => r.Value.GetInt32())
-                    .Select(r => new { r.Value, r.Count }));
+                    .Select(r => new { r.Value, r.Count })
+                    .ToList());
             yield return new UntypedMetric("text.length.counts", result.ValueCounts);
         }