[OTLP Exporter] Configurable gRPC ChannelOptions (#1033)

* Allow gRPC ChannelOptions

* Adding to the changelog

Co-authored-by: Cijo Thomas <cithomas@microsoft.com>

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/CHANGELOG.md

@@ -2,6 +2,9 @@
 
 ## Unreleased
 
+* Allow configurable gRPC channel options
+  ([#1033](https://github.com/open-telemetry/opentelemetry-dotnet/pull/1033))
+
 ## 0.3.0-beta
 
 Released 2020-07-23

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/OtlpExporter.cs

@@ -45,7 +45,7 @@ namespace OpenTelemetry.Exporter.OpenTelemetryProtocol
         public OtlpExporter(OtlpExporterOptions options)
         {
             this.headers = options.Headers;
-            this.channel = new Channel(options.Endpoint, options.Credentials);
+            this.channel = new Channel(options.Endpoint, options.Credentials, options.ChannelOptions);
             this.traceClient = new OtlpCollector.TraceService.TraceServiceClient(this.channel);
         }
 

src/OpenTelemetry.Exporter.OpenTelemetryProtocol/OtlpExporterOptions.cs

@@ -14,6 +14,7 @@
 // limitations under the License.
 // </copyright>
 
+using System.Collections.Generic;
 using Grpc.Core;
 
 namespace OpenTelemetry.Exporter.OpenTelemetryProtocol
@@ -38,6 +39,11 @@ namespace OpenTelemetry.Exporter.OpenTelemetryProtocol
         /// <summary>
         /// Gets or sets optional headers for the connection.
         /// </summary>
-        public Metadata Headers { get; set; } = new Metadata();
+        public Metadata Headers { get; set; } = new Metadata();
+
+        /// <summary>
+        /// Gets or sets the gRPC channel options.
+        /// </summary>
+        public IEnumerable<ChannelOption> ChannelOptions { get; set; }
     }
 }