forked from mirror/client_golang
100 lines
3.0 KiB
Go
100 lines
3.0 KiB
Go
![]() |
// Copyright 2013 Prometheus Team
|
||
|
// 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 decoding
|
||
|
|
||
|
import (
|
||
|
"io"
|
||
|
"time"
|
||
|
)
|
||
|
|
||
|
const (
|
||
|
// The label name prefix to prepend if a synthetic label is already present
|
||
|
// in the exported metrics.
|
||
|
ExporterLabelPrefix = LabelName("exporter_")
|
||
|
|
||
|
// The label name indicating the metric name of a timeseries.
|
||
|
MetricNameLabel = LabelName("name")
|
||
|
|
||
|
// The label name indicating the job from which a timeseries was scraped.
|
||
|
JobLabel = LabelName("job")
|
||
|
)
|
||
|
|
||
|
// ProcessOptions dictates how the interpreted stream should be rendered for
|
||
|
// consumption.
|
||
|
type ProcessOptions struct {
|
||
|
// Timestamp is added to each value interpreted from the stream.
|
||
|
Timestamp time.Time
|
||
|
|
||
|
// BaseLabels are labels that are accumulated onto each sample, if any.
|
||
|
BaseLabels LabelSet
|
||
|
}
|
||
|
|
||
|
// Processor is responsible for decoding the actual message responses from
|
||
|
// stream into a format that can be consumed with the end result written
|
||
|
// to the results channel.
|
||
|
type Processor interface {
|
||
|
// ProcessSingle treats the input as a single self-contained message body and
|
||
|
// transforms it accordingly. It has no support for streaming.
|
||
|
ProcessSingle(in io.Reader, out chan<- *Result, o *ProcessOptions) error
|
||
|
}
|
||
|
|
||
|
// Helper function to convert map[string]string into LabelSet.
|
||
|
//
|
||
|
// NOTE: This should be deleted when support for go 1.0.3 is removed; 1.1 is
|
||
|
// smart enough to unmarshal JSON objects into LabelSet directly.
|
||
|
func labelSet(labels map[string]string) LabelSet {
|
||
|
labelset := make(LabelSet, len(labels))
|
||
|
|
||
|
for k, v := range labels {
|
||
|
labelset[LabelName(k)] = LabelValue(v)
|
||
|
}
|
||
|
|
||
|
return labelset
|
||
|
}
|
||
|
|
||
|
// Helper function to merge a target's base labels ontop of the labels of an
|
||
|
// exported sample. If a label is already defined in the exported sample, we
|
||
|
// assume that we are scraping an intermediate exporter and attach
|
||
|
// "exporter_"-prefixes to Prometheus' own base labels.
|
||
|
func mergeTargetLabels(entityLabels, targetLabels LabelSet) LabelSet {
|
||
|
if targetLabels == nil {
|
||
|
targetLabels = LabelSet{}
|
||
|
}
|
||
|
|
||
|
result := LabelSet{}
|
||
|
|
||
|
for label, value := range entityLabels {
|
||
|
result[label] = value
|
||
|
}
|
||
|
|
||
|
for label, labelValue := range targetLabels {
|
||
|
if _, exists := result[label]; exists {
|
||
|
result[ExporterLabelPrefix+label] = labelValue
|
||
|
} else {
|
||
|
result[label] = labelValue
|
||
|
}
|
||
|
}
|
||
|
return result
|
||
|
}
|
||
|
|
||
|
// Result encapsulates the outcome from processing samples from a source.
|
||
|
type Result struct {
|
||
|
Err error
|
||
|
Samples Samples
|
||
|
}
|
||
|
|
||
|
// A LabelName is a key for a LabelSet or Metric. It has a value associated
|
||
|
// therewith.
|
||
|
type LabelName string
|