Added OpenTelementryProtocol/metric/

and stubbed MetricsAdapter & OtelpMetricExporter

Author: bryce-b

Sources/Exporters/OpenTelemetryProtocol/metric/MetricsAdapter.swift

@@ -0,0 +1,29 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+import Foundation
+import OpenTelemetryApi
+import OpenTelemetrySdk
+
+
+struct MetricsAdapter {
+    static func toProtoResourceMetrics(metricDataList: [MetricData]) -> [Opentelemetry_Proto_Metrics_V1_ResourceMetrics] {
+        return [Opentelemetry_Proto_Metrics_V1_ResourceMetrics()]
+    }
+    
+    private static func groupByLibrary(metricDataList: [MetricData]) ->  [InstrumentationLibraryInfo : Opentelemetry_Proto_Metrics_V1_ResourceMetrics] {
+        return results
+    }
+    
+}

Sources/Exporters/OpenTelemetryProtocol/metric/OtelpMetricExporter.swift

@@ -0,0 +1,41 @@
+// Copyright 2020, OpenTelemetry Authors
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+import GRPC
+import OpenTelemetryApi
+import OpenTelemetrySdk
+
+public class OtelpMetricExporter : MetricExporter {
+    
+    let channel : GRPCChannel
+    let metricClient: Opentelemetry_Proto_Collector_Metrics_V1_MetricsServiceClient
+    let deadlineMS : Int
+    
+    public init(channel: GRPCChannel, timeoutMS: Int) {
+        self.channel = channel
+        self.deadlineMS = timeoutMS
+        self.metricClient = Opentelemetry_Proto_Collector_Metrics_V1_MetricsServiceClient(channel: self.channel)
+    }
+    
+    
+    public func export(metrics: [Metric], shouldCancel: (() -> Bool)?) -> MetricExporterResultCode {
+        return .success
+    }
+    
+    
+    
+    
+}