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+// Copyright 2018 Google LLC.
+//
+// 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.
+//
+
+syntax = "proto3";
+
+package google.monitoring.v3;
+
+option csharp_namespace = "Google.Cloud.Monitoring.V3";
+option go_package = "google.golang.org/genproto/googleapis/monitoring/v3;monitoring";
+option java_multiple_files = true;
+option java_outer_classname = "SpanContextProto";
+option java_package = "com.google.monitoring.v3";
+option php_namespace = "Google\\Cloud\\Monitoring\\V3";
+
+// The context of a span, attached to google.api.Distribution.Exemplars
+// in google.api.Distribution values during aggregation.
+//
+// It contains the name of a span with format:
+// projects/[PROJECT_ID]/traces/[TRACE_ID]/spans/[SPAN_ID]
+message SpanContext {
+ // The resource name of the span in the following format:
+ //
+ // projects/[PROJECT_ID]/traces/[TRACE_ID]/spans/[SPAN_ID]
+ //
+ // [TRACE_ID] is a unique identifier for a trace within a project;
+ // it is a 32-character hexadecimal encoding of a 16-byte array.
+ //
+ // [SPAN_ID] is a unique identifier for a span within a trace; it
+ // is a 16-character hexadecimal encoding of an 8-byte array.
+ string span_name = 1;
+}