Merge branch 'main' into feature/enable-successfulcommandtest-by-leve…

…raging-testcontainers

.github/workflows/stale.yml

@@ -10,7 +10,7 @@ jobs:
   stale:
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/stale@v7
+      - uses: actions/stale@v8
         with:
           stale-pr-message: 'This PR was marked stale due to lack of activity and will be closed in 7 days. Commenting or Pushing will instruct the bot to automatically remove the label. This bot runs once per day.'
           close-pr-message: 'Closed as inactive. Feel free to reopen if this PR is still being worked on.'

examples/AspNetCore/Program.cs

@@ -14,6 +14,7 @@
 // limitations under the License.
 // </copyright>
 
+using System.Diagnostics.Metrics;
 using Examples.AspNetCore;
 using OpenTelemetry.Exporter;
 using OpenTelemetry.Instrumentation.AspNetCore;
@@ -33,6 +34,9 @@
 // Note: Switch between Console/OTLP by setting UseLogExporter in appsettings.json.
 var logExporter = appBuilder.Configuration.GetValue<string>("UseLogExporter").ToLowerInvariant();
 
+// Note: Switch between Explicit/Exponential by setting HistogramAggregation in appsettings.json
+var histogramAggregation = appBuilder.Configuration.GetValue<string>("HistogramAggregation").ToLowerInvariant();
+
 // Build a resource configuration action to set service information.
 Action<ResourceBuilder> configureResource = r => r.AddService(
     serviceName: appBuilder.Configuration.GetValue<string>("ServiceName"),
@@ -111,6 +115,22 @@
             .AddHttpClientInstrumentation()
             .AddAspNetCoreInstrumentation();
 
+        switch (histogramAggregation)
+        {
+            case "exponential":
+                builder.AddView(instrument =>
+                {
+                    return instrument.GetType().GetGenericTypeDefinition() == typeof(Histogram<>)
+                        ? new Base2ExponentialBucketHistogramConfiguration()
+                        : null;
+                });
+                break;
+            default:
+                // Explicit bounds histogram is the default.
+                // No additional configuration necessary.
+                break;
+        }
+
         switch (metricsExporter)
         {
             case "prometheus":

examples/AspNetCore/appsettings.json

@@ -14,6 +14,7 @@
   "UseTracingExporter": "console",
   "UseMetricsExporter": "console",
   "UseLogExporter": "console",
+  "HistogramAggregation": "explicit",
   "Jaeger": {
     "AgentHost": "localhost",
     "AgentPort": 6831,

src/OpenTelemetry.Api/Internal/ExceptionExtensions.cs

@@ -14,6 +14,8 @@
 // limitations under the License.
 // </copyright>
 
+#nullable enable
+
 using System.Globalization;
 
 namespace OpenTelemetry.Internal

src/OpenTelemetry.Api/Internal/SemanticConventions.cs

@@ -14,6 +14,8 @@
 // limitations under the License.
 // </copyright>
 
+#nullable enable
+
 namespace OpenTelemetry.Trace
 {
     /// <summary>

src/OpenTelemetry.Api/Internal/SpanAttributeConstants.cs

@@ -14,6 +14,8 @@
 // limitations under the License.
 // </copyright>
 
+#nullable enable
+
 namespace OpenTelemetry.Trace
 {
     /// <summary>

src/OpenTelemetry.Api/Internal/StatusHelper.cs

@@ -14,6 +14,8 @@
 // limitations under the License.
 // </copyright>
 
+#nullable enable
+
 using System.Runtime.CompilerServices;
 using OpenTelemetry.Trace;
 
@@ -26,7 +28,7 @@ internal static class StatusHelper
         public const string ErrorStatusCodeTagValue = "ERROR";
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static string GetTagValueForStatusCode(StatusCode statusCode)
+        public static string? GetTagValueForStatusCode(StatusCode statusCode)
         {
             return statusCode switch
             {
@@ -43,7 +45,7 @@ public static string GetTagValueForStatusCode(StatusCode statusCode)
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static StatusCode? GetStatusCodeForTagValue(string statusCodeTagValue)
+        public static StatusCode? GetStatusCodeForTagValue(string? statusCodeTagValue)
         {
             return statusCodeTagValue switch
             {
@@ -52,15 +54,15 @@ public static string GetTagValueForStatusCode(StatusCode statusCode)
                  * first because assumption is most spans will be
                  * Unset, then Error. Ok is not set by the SDK.
                  */
-                string _ when UnsetStatusCodeTagValue.Equals(statusCodeTagValue, StringComparison.OrdinalIgnoreCase) => StatusCode.Unset,
-                string _ when ErrorStatusCodeTagValue.Equals(statusCodeTagValue, StringComparison.OrdinalIgnoreCase) => StatusCode.Error,
-                string _ when OkStatusCodeTagValue.Equals(statusCodeTagValue, StringComparison.OrdinalIgnoreCase) => StatusCode.Ok,
+                not null when UnsetStatusCodeTagValue.Equals(statusCodeTagValue, StringComparison.OrdinalIgnoreCase) => StatusCode.Unset,
+                not null when ErrorStatusCodeTagValue.Equals(statusCodeTagValue, StringComparison.OrdinalIgnoreCase) => StatusCode.Error,
+                not null when OkStatusCodeTagValue.Equals(statusCodeTagValue, StringComparison.OrdinalIgnoreCase) => StatusCode.Ok,
                 _ => null,
             };
         }
 
         [MethodImpl(MethodImplOptions.AggressiveInlining)]
-        public static bool TryGetStatusCodeForTagValue(string statusCodeTagValue, out StatusCode statusCode)
+        public static bool TryGetStatusCodeForTagValue(string? statusCodeTagValue, out StatusCode statusCode)
         {
             StatusCode? tempStatusCode = GetStatusCodeForTagValue(statusCodeTagValue);
 

src/OpenTelemetry.Api/README.md

@@ -452,6 +452,21 @@ and
 [extract](../../examples/MicroserviceExample/Utils/Messaging/MessageReceiver.cs)
 context.
 
+**Note on instrumentation libraries**: If you are using the instrumentation
+libraries shipped from this repo [e.g. [ASP.NET
+Core](https://github.com/open-telemetry/opentelemetry-dotnet/tree/main/src/OpenTelemetry.Instrumentation.AspNetCore)
+or
+[HttpClient](https://github.com/open-telemetry/opentelemetry-dotnet/tree/main/src/OpenTelemetry.Instrumentation.Http)],
+context propagation is done by using the
+[default](https://github.com/open-telemetry/opentelemetry-dotnet/blob/d924663dc3d6bfdf737bc49ceaa1addcec90a2d6/src/OpenTelemetry/Sdk.cs#L34-L38)
+propagator. The default can be updated by calling
+`Sdk.SetDefaultTextMapPropagator` and passing the propagator of your choice.
+
+Propagator Api used by the instrumentation libraries is different than
+[DistributedContextPropagator](https://learn.microsoft.com/dotnet/api/system.diagnostics.distributedcontextpropagator)
+available in `System.Diagnostics`. Implementing this will have no impact on the
+propagation, if used alongside instrumentation libraries.
+
 ## Introduction to OpenTelemetry .NET Metrics API
 
 Metrics in OpenTelemetry .NET are a somewhat unique implementation of the

src/OpenTelemetry.Exporter.Console/ConsoleMetricExporter.cs

@@ -92,7 +92,7 @@ public override ExportResult Export(in Batch<Metric> batch)
 
                     var metricType = metric.MetricType;
 
-                    if (metricType.IsHistogram())
+                    if (metricType == MetricType.Histogram || metricType == MetricType.ExponentialHistogram)
                     {
                         var bucketsBuilder = new StringBuilder();
                         var sum = metricPoint.GetHistogramSum();
@@ -105,41 +105,49 @@ public override ExportResult Export(in Batch<Metric> batch)
 
                         bucketsBuilder.AppendLine();
 
-                        bool isFirstIteration = true;
-                        double previousExplicitBound = default;
-                        foreach (var histogramMeasurement in metricPoint.GetHistogramBuckets())
+                        if (metricType == MetricType.Histogram)
                         {
-                            if (isFirstIteration)
+                            bool isFirstIteration = true;
+                            double previousExplicitBound = default;
+                            foreach (var histogramMeasurement in metricPoint.GetHistogramBuckets())
                             {
-                                bucketsBuilder.Append("(-Infinity,");
-                                bucketsBuilder.Append(histogramMeasurement.ExplicitBound);
-                                bucketsBuilder.Append(']');
-                                bucketsBuilder.Append(':');
-                                bucketsBuilder.Append(histogramMeasurement.BucketCount);
-                                previousExplicitBound = histogramMeasurement.ExplicitBound;
-                                isFirstIteration = false;
-                            }
-                            else
-                            {
-                                bucketsBuilder.Append('(');
-                                bucketsBuilder.Append(previousExplicitBound);
-                                bucketsBuilder.Append(',');
-                                if (histogramMeasurement.ExplicitBound != double.PositiveInfinity)
+                                if (isFirstIteration)
                                 {
+                                    bucketsBuilder.Append("(-Infinity,");
                                     bucketsBuilder.Append(histogramMeasurement.ExplicitBound);
+                                    bucketsBuilder.Append(']');
+                                    bucketsBuilder.Append(':');
+                                    bucketsBuilder.Append(histogramMeasurement.BucketCount);
                                     previousExplicitBound = histogramMeasurement.ExplicitBound;
+                                    isFirstIteration = false;
                                 }
                                 else
                                 {
-                                    bucketsBuilder.Append("+Infinity");
+                                    bucketsBuilder.Append('(');
+                                    bucketsBuilder.Append(previousExplicitBound);
+                                    bucketsBuilder.Append(',');
+                                    if (histogramMeasurement.ExplicitBound != double.PositiveInfinity)
+                                    {
+                                        bucketsBuilder.Append(histogramMeasurement.ExplicitBound);
+                                        previousExplicitBound = histogramMeasurement.ExplicitBound;
+                                    }
+                                    else
+                                    {
+                                        bucketsBuilder.Append("+Infinity");
+                                    }
+
+                                    bucketsBuilder.Append(']');
+                                    bucketsBuilder.Append(':');
+                                    bucketsBuilder.Append(histogramMeasurement.BucketCount);
                                 }
 
-                                bucketsBuilder.Append(']');
-                                bucketsBuilder.Append(':');
-                                bucketsBuilder.Append(histogramMeasurement.BucketCount);
+                                bucketsBuilder.AppendLine();
                             }
-
-                            bucketsBuilder.AppendLine();
+                        }
+                        else
+                        {
+                            // TODO: Consider how/if to display buckets for exponential histograms.
+                            bucketsBuilder.AppendLine("Buckets are not displayed for exponential histograms.");
                         }
 
                         valueDisplay = bucketsBuilder.ToString();

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/CHANGELOG.md

@@ -2,6 +2,15 @@
 
 ## Unreleased
 
+* Add support for exporting histograms aggregated using the
+  [Base2 Exponential Bucket Histogram Aggregation](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/metrics/sdk.md#base2-exponential-bucket-histogram-aggregation).
+  ([#4337](https://github.com/open-telemetry/opentelemetry-dotnet/pull/4337))
+
+* Added support to set `TraceState` when converting the
+  System.Diagnostics.Activity object to its corresponding
+  OpenTelemetry.Proto.Trace.V1.Span object.
+  ([#4331](https://github.com/open-telemetry/opentelemetry-dotnet/pull/4331))
+
 ## 1.5.0-alpha.1
 
 Released 2023-Mar-07

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/ActivityExtensions.cs

@@ -143,6 +143,7 @@ internal static Span ToOtlpSpan(this Activity activity, SdkLimitOptions sdkLimit
                 TraceId = UnsafeByteOperations.UnsafeWrap(traceIdBytes),
                 SpanId = UnsafeByteOperations.UnsafeWrap(spanIdBytes),
                 ParentSpanId = parentSpanIdString,
+                TraceState = activity.TraceStateString ?? string.Empty,
 
                 StartTimeUnixNano = (ulong)startTimeUnixNano,
                 EndTimeUnixNano = (ulong)(startTimeUnixNano + activity.Duration.ToNanoseconds()),

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/Implementation/MetricItemExtensions.cs

@@ -307,6 +307,58 @@ internal static OtlpMetrics.Metric ToOtlpMetric(this Metric metric)
                         otlpMetric.Histogram = histogram;
                         break;
                     }
+
+                case MetricType.ExponentialHistogram:
+                    {
+                        var histogram = new OtlpMetrics.ExponentialHistogram
+                        {
+                            AggregationTemporality = temporality,
+                        };
+
+                        foreach (ref readonly var metricPoint in metric.GetMetricPoints())
+                        {
+                            var dataPoint = new OtlpMetrics.ExponentialHistogramDataPoint
+                            {
+                                StartTimeUnixNano = (ulong)metricPoint.StartTime.ToUnixTimeNanoseconds(),
+                                TimeUnixNano = (ulong)metricPoint.EndTime.ToUnixTimeNanoseconds(),
+                            };
+
+                            AddAttributes(metricPoint.Tags, dataPoint.Attributes);
+                            dataPoint.Count = (ulong)metricPoint.GetHistogramCount();
+                            dataPoint.Sum = metricPoint.GetHistogramSum();
+
+                            if (metricPoint.TryGetHistogramMinMaxValues(out double min, out double max))
+                            {
+                                dataPoint.Min = min;
+                                dataPoint.Max = max;
+                            }
+
+                            var exponentialHistogramData = metricPoint.GetExponentialHistogramData();
+                            dataPoint.Scale = exponentialHistogramData.Scale;
+                            dataPoint.ZeroCount = (ulong)exponentialHistogramData.ZeroCount;
+
+                            dataPoint.Positive = new OtlpMetrics.ExponentialHistogramDataPoint.Types.Buckets();
+                            dataPoint.Positive.Offset = exponentialHistogramData.PositiveBuckets.Offset;
+                            foreach (var bucketCount in exponentialHistogramData.PositiveBuckets)
+                            {
+                                dataPoint.Positive.BucketCounts.Add((ulong)bucketCount);
+                            }
+
+                            dataPoint.Negative = new OtlpMetrics.ExponentialHistogramDataPoint.Types.Buckets();
+                            dataPoint.Negative.Offset = exponentialHistogramData.NegativeBuckets.Offset;
+                            foreach (var bucketCount in exponentialHistogramData.NegativeBuckets)
+                            {
+                                dataPoint.Negative.BucketCounts.Add((ulong)bucketCount);
+                            }
+
+                            // TODO: exemplars.
+
+                            histogram.DataPoints.Add(dataPoint);
+                        }
+
+                        otlpMetric.ExponentialHistogram = histogram;
+                        break;
+                    }
             }
 
             return otlpMetric;

src/OpenTelemetry.Exporter.Prometheus.HttpListener/Internal/PrometheusSerializerExt.cs

@@ -36,6 +36,13 @@ UpDownCounter becomes gauge
 
         public static int WriteMetric(byte[] buffer, int cursor, Metric metric)
         {
+            if (metric.MetricType == MetricType.ExponentialHistogram)
+            {
+                // Exponential histograms are not yet support by Prometheus.
+                // They are ignored for now.
+                return cursor;
+            }
+
             int metricType = (int)metric.MetricType >> 4;
             cursor = WriteTypeMetadata(buffer, cursor, metric.Name, metric.Unit, MetricTypes[metricType]);
             cursor = WriteUnitMetadata(buffer, cursor, metric.Name, metric.Unit);