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Diffstat (limited to 'vendor/github.com/prometheus/common/model/metric.go')
-rw-r--r-- | vendor/github.com/prometheus/common/model/metric.go | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/vendor/github.com/prometheus/common/model/metric.go b/vendor/github.com/prometheus/common/model/metric.go new file mode 100644 index 000000000..00804b7fe --- /dev/null +++ b/vendor/github.com/prometheus/common/model/metric.go @@ -0,0 +1,102 @@ +// Copyright 2013 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 model + +import ( + "fmt" + "regexp" + "sort" + "strings" +) + +var ( + // MetricNameRE is a regular expression matching valid metric + // names. Note that the IsValidMetricName function performs the same + // check but faster than a match with this regular expression. + MetricNameRE = regexp.MustCompile(`^[a-zA-Z_:][a-zA-Z0-9_:]*$`) +) + +// A Metric is similar to a LabelSet, but the key difference is that a Metric is +// a singleton and refers to one and only one stream of samples. +type Metric LabelSet + +// Equal compares the metrics. +func (m Metric) Equal(o Metric) bool { + return LabelSet(m).Equal(LabelSet(o)) +} + +// Before compares the metrics' underlying label sets. +func (m Metric) Before(o Metric) bool { + return LabelSet(m).Before(LabelSet(o)) +} + +// Clone returns a copy of the Metric. +func (m Metric) Clone() Metric { + clone := make(Metric, len(m)) + for k, v := range m { + clone[k] = v + } + return clone +} + +func (m Metric) String() string { + metricName, hasName := m[MetricNameLabel] + numLabels := len(m) - 1 + if !hasName { + numLabels = len(m) + } + labelStrings := make([]string, 0, numLabels) + for label, value := range m { + if label != MetricNameLabel { + labelStrings = append(labelStrings, fmt.Sprintf("%s=%q", label, value)) + } + } + + switch numLabels { + case 0: + if hasName { + return string(metricName) + } + return "{}" + default: + sort.Strings(labelStrings) + return fmt.Sprintf("%s{%s}", metricName, strings.Join(labelStrings, ", ")) + } +} + +// Fingerprint returns a Metric's Fingerprint. +func (m Metric) Fingerprint() Fingerprint { + return LabelSet(m).Fingerprint() +} + +// FastFingerprint returns a Metric's Fingerprint calculated by a faster hashing +// algorithm, which is, however, more susceptible to hash collisions. +func (m Metric) FastFingerprint() Fingerprint { + return LabelSet(m).FastFingerprint() +} + +// IsValidMetricName returns true iff name matches the pattern of MetricNameRE. +// This function, however, does not use MetricNameRE for the check but a much +// faster hardcoded implementation. +func IsValidMetricName(n LabelValue) bool { + if len(n) == 0 { + return false + } + for i, b := range n { + if !((b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || b == '_' || b == ':' || (b >= '0' && b <= '9' && i > 0)) { + return false + } + } + return true +} |