Add Resource support for MetricProvider (#2150)

Author: cijothomas

examples/Console/TestMetrics.cs

@@ -21,8 +21,8 @@
 using System.Threading;
 using System.Threading.Tasks;
 using OpenTelemetry;
-using OpenTelemetry.Exporter;
 using OpenTelemetry.Metrics;
+using OpenTelemetry.Resources;
 
 namespace Examples.Console
 {
@@ -31,6 +31,7 @@ internal class TestMetrics
         internal static object Run(MetricsOptions options)
         {
             var providerBuilder = Sdk.CreateMeterProviderBuilder()
+                .SetResourceBuilder(ResourceBuilder.CreateDefault().AddService("myservice"))
                 .AddSource("TestMeter"); // All instruments from this meter are enabled.
 
             if (options.UseExporter.ToLower() == "otlp")

src/OpenTelemetry.Exporter.Console/ConsoleMetricExporter.cs

@@ -19,18 +19,36 @@
 using System.Linq;
 using System.Text;
 using OpenTelemetry.Metrics;
+using OpenTelemetry.Resources;
 
 namespace OpenTelemetry.Exporter
 {
     public class ConsoleMetricExporter : ConsoleExporter<MetricItem>
     {
+        private Resource resource;
+
         public ConsoleMetricExporter(ConsoleExporterOptions options)
             : base(options)
         {
         }
 
         public override ExportResult Export(in Batch<MetricItem> batch)
         {
+            if (this.resource == null)
+            {
+                this.resource = this.ParentProvider.GetResource();
+                if (this.resource != Resource.Empty)
+                {
+                    foreach (var resourceAttribute in this.resource.Attributes)
+                    {
+                        if (resourceAttribute.Key.Equals("service.name"))
+                        {
+                            Console.WriteLine("Service.Name" + resourceAttribute.Value);
+                        }
+                    }
+                }
+            }
+
             foreach (var metricItem in batch)
             {
                 foreach (var metric in metricItem.Metrics)

src/OpenTelemetry/Metrics/MeterProviderBuilderExtensions.cs

@@ -14,6 +14,8 @@
 // limitations under the License.
 // </copyright>
 
+using OpenTelemetry.Resources;
+
 namespace OpenTelemetry.Metrics
 {
     /// <summary>
@@ -53,6 +55,23 @@ public static MeterProviderBuilder AddMetricProcessor(this MeterProviderBuilder
             return meterProviderBuilder;
         }
 
+        /// <summary>
+        /// Sets the <see cref="ResourceBuilder"/> from which the Resource associated with
+        /// this provider is built from. Overwrites currently set ResourceBuilder.
+        /// </summary>
+        /// <param name="meterProviderBuilder">MeterProviderBuilder instance.</param>
+        /// <param name="resourceBuilder"><see cref="ResourceBuilder"/> from which Resource will be built.</param>
+        /// <returns>Returns <see cref="MeterProviderBuilder"/> for chaining.</returns>
+        public static MeterProviderBuilder SetResourceBuilder(this MeterProviderBuilder meterProviderBuilder, ResourceBuilder resourceBuilder)
+        {
+            if (meterProviderBuilder is MeterProviderBuilderSdk meterProviderBuilderSdk)
+            {
+                meterProviderBuilderSdk.SetResourceBuilder(resourceBuilder);
+            }
+
+            return meterProviderBuilder;
+        }
+
         /// <summary>
         /// Run the given actions to initialize the <see cref="MeterProvider"/>.
         /// </summary>

src/OpenTelemetry/Metrics/MeterProviderBuilderSdk.cs

@@ -16,12 +16,14 @@
 
 using System;
 using System.Collections.Generic;
+using OpenTelemetry.Resources;
 
 namespace OpenTelemetry.Metrics
 {
     internal class MeterProviderBuilderSdk : MeterProviderBuilder
     {
         private readonly List<string> meterSources = new List<string>();
+        private ResourceBuilder resourceBuilder = ResourceBuilder.CreateDefault();
 
         internal MeterProviderBuilderSdk()
         {
@@ -63,9 +65,16 @@ internal MeterProviderBuilderSdk AddMetricProcessor(MetricProcessor processor)
             return this;
         }
 
+        internal MeterProviderBuilderSdk SetResourceBuilder(ResourceBuilder resourceBuilder)
+        {
+            this.resourceBuilder = resourceBuilder ?? throw new ArgumentNullException(nameof(resourceBuilder));
+            return this;
+        }
+
         internal MeterProvider Build()
         {
             return new MeterProviderSdk(
+                this.resourceBuilder.Build(),
                 this.meterSources,
                 this.MeasurementProcessors.ToArray(),
                 this.MetricProcessors.ToArray());

src/OpenTelemetry/Metrics/MeterProviderSdk.cs

@@ -18,10 +18,9 @@
 using System.Collections.Concurrent;
 using System.Collections.Generic;
 using System.Diagnostics.Metrics;
-using System.Linq;
-using System.Runtime.CompilerServices;
 using System.Threading;
 using System.Threading.Tasks;
+using OpenTelemetry.Resources;
 
 namespace OpenTelemetry.Metrics
 {
@@ -38,16 +37,19 @@ public class MeterProviderSdk
         private readonly List<MetricProcessor> metricProcessors = new List<MetricProcessor>();
 
         internal MeterProviderSdk(
+            Resource resource,
             IEnumerable<string> meterSources,
             MeasurementProcessor[] measurementProcessors,
             MetricProcessor[] metricProcessors)
         {
+            this.Resource = resource;
             this.measurementProcessors.AddRange(measurementProcessors);
             this.metricProcessors.AddRange(metricProcessors);
 
             foreach (var processor in this.metricProcessors)
             {
                 processor.SetGetMetricFunction(this.Collect);
+                processor.SetParentProvider(this);
             }
 
             // Setup Listener
@@ -83,6 +85,8 @@ internal MeterProviderSdk(
             this.listener.Start();
         }
 
+        internal Resource Resource { get; }
+
         internal void MeasurementsCompleted(Instrument instrument, object state)
         {
             Console.WriteLine($"Instrument {instrument.Meter.Name}:{instrument.Name} completed.");

src/OpenTelemetry/Metrics/Processors/MetricProcessor.cs

@@ -20,8 +20,22 @@ namespace OpenTelemetry.Metrics
 {
     public abstract class MetricProcessor : BaseProcessor<MetricItem>
     {
+        protected readonly BaseExporter<MetricItem> exporter;
+
+        protected MetricProcessor(BaseExporter<MetricItem> exporter)
+        {
+            this.exporter = exporter ?? throw new ArgumentNullException(nameof(exporter));
+        }
+
         // GetMetric or GetMemoryState or GetAggregatedMetrics..
         // ...or some other names
         public abstract void SetGetMetricFunction(Func<bool, MetricItem> getMetrics);
+
+        internal override void SetParentProvider(BaseProvider parentProvider)
+        {
+            base.SetParentProvider(parentProvider);
+
+            this.exporter.ParentProvider = parentProvider;
+        }
     }
 }

src/OpenTelemetry/Metrics/Processors/PullMetricProcessor.cs

@@ -23,13 +23,12 @@ namespace OpenTelemetry.Metrics
     public class PullMetricProcessor : MetricProcessor, IDisposable
     {
         private Func<bool, MetricItem> getMetrics;
-        private BaseExporter<MetricItem> exporter;
         private bool disposed;
         private bool isDelta;
 
         public PullMetricProcessor(BaseExporter<MetricItem> exporter, bool isDelta)
+            : base(exporter)
         {
-            this.exporter = exporter;
             this.isDelta = isDelta;
         }
 

src/OpenTelemetry/Metrics/Processors/PushMetricProcessor.cs

@@ -26,13 +26,12 @@ public class PushMetricProcessor : MetricProcessor, IDisposable
         private CancellationTokenSource token;
         private int exportIntervalMs;
         private Func<bool, MetricItem> getMetrics;
-        private BaseExporter<MetricItem> exporter;
         private bool disposed;
 
         public PushMetricProcessor(BaseExporter<MetricItem> exporter, int exportIntervalMs, bool isDelta)
+            : base(exporter)
         {
             this.exportIntervalMs = exportIntervalMs;
-            this.exporter = exporter;
             this.token = new CancellationTokenSource();
             this.exportTask = new Task(() =>
             {

src/OpenTelemetry/ProviderExtensions.cs

@@ -17,6 +17,7 @@
 #if NET461 || NETSTANDARD2_0
 using OpenTelemetry.Logs;
 #endif
+using OpenTelemetry.Metrics;
 using OpenTelemetry.Resources;
 using OpenTelemetry.Trace;
 
@@ -44,6 +45,10 @@ public static Resource GetResource(this BaseProvider baseProvider)
                 return otelLoggerProvider.Resource;
             }
 #endif
+            else if (baseProvider is MeterProviderSdk meterProviderSdk)
+            {
+                return meterProviderSdk.Resource;
+            }
 
             return Resource.Empty;
         }