forked from mirror/client_golang
89 lines
2.5 KiB
Go
89 lines
2.5 KiB
Go
// Copyright 2018 The Prometheus 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.
|
|
|
|
package prometheus
|
|
|
|
import (
|
|
"errors"
|
|
"fmt"
|
|
"strings"
|
|
"unicode/utf8"
|
|
|
|
"github.com/prometheus/common/model"
|
|
)
|
|
|
|
// Labels represents a collection of label name -> value mappings. This type is
|
|
// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
|
|
// metric vector Collectors, e.g.:
|
|
//
|
|
// myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
|
|
//
|
|
// The other use-case is the specification of constant label pairs in Opts or to
|
|
// create a Desc.
|
|
type Labels map[string]string
|
|
|
|
// reservedLabelPrefix is a prefix which is not legal in user-supplied
|
|
// label names.
|
|
const reservedLabelPrefix = "__"
|
|
|
|
var errInconsistentCardinality = errors.New("inconsistent label cardinality")
|
|
|
|
func makeInconsistentCardinalityError(fqName string, labels, labelValues []string) error {
|
|
return fmt.Errorf(
|
|
"%w: %q has %d variable labels named %q but %d values %q were provided",
|
|
errInconsistentCardinality, fqName,
|
|
len(labels), labels,
|
|
len(labelValues), labelValues,
|
|
)
|
|
}
|
|
|
|
func validateValuesInLabels(labels Labels, expectedNumberOfValues int) error {
|
|
if len(labels) != expectedNumberOfValues {
|
|
return fmt.Errorf(
|
|
"%w: expected %d label values but got %d in %#v",
|
|
errInconsistentCardinality, expectedNumberOfValues,
|
|
len(labels), labels,
|
|
)
|
|
}
|
|
|
|
for name, val := range labels {
|
|
if !utf8.ValidString(val) {
|
|
return fmt.Errorf("label %s: value %q is not valid UTF-8", name, val)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func validateLabelValues(vals []string, expectedNumberOfValues int) error {
|
|
if len(vals) != expectedNumberOfValues {
|
|
return fmt.Errorf(
|
|
"%w: expected %d label values but got %d in %#v",
|
|
errInconsistentCardinality, expectedNumberOfValues,
|
|
len(vals), vals,
|
|
)
|
|
}
|
|
|
|
for _, val := range vals {
|
|
if !utf8.ValidString(val) {
|
|
return fmt.Errorf("label value %q is not valid UTF-8", val)
|
|
}
|
|
}
|
|
|
|
return nil
|
|
}
|
|
|
|
func checkLabelName(l string) bool {
|
|
return model.LabelName(l).IsValid() && !strings.HasPrefix(l, reservedLabelPrefix)
|
|
}
|