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 15 package metricdata 16 17 // LabelKey represents key of a label. It has optional 18 // description attribute. 19 type LabelKey struct { 20 Key string 21 Description string 22 } 23 24 // LabelValue represents the value of a label. 25 // The zero value represents a missing label value, which may be treated 26 // differently to an empty string value by some back ends. 27 type LabelValue struct { 28 Value string // string value of the label 29 Present bool // flag that indicated whether a value is present or not 30 } 31 32 // NewLabelValue creates a new non-nil LabelValue that represents the given string. 33 func NewLabelValue(val string) LabelValue { 34 return LabelValue{Value: val, Present: true} 35 } 36