1// Copyright 2018, OpenCensus Authors
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15package metricdata
16
17import (
18	"time"
19)
20
21// Exemplars keys.
22const (
23	AttachmentKeySpanContext = "SpanContext"
24)
25
26// Exemplar is an example data point associated with each bucket of a
27// distribution type aggregation.
28//
29// Their purpose is to provide an example of the kind of thing
30// (request, RPC, trace span, etc.) that resulted in that measurement.
31type Exemplar struct {
32	Value       float64     // the value that was recorded
33	Timestamp   time.Time   // the time the value was recorded
34	Attachments Attachments // attachments (if any)
35}
36
37// Attachments is a map of extra values associated with a recorded data point.
38type Attachments map[string]interface{}
39