mirror of
https://github.com/prometheus/prometheus.git
synced 2024-12-26 22:19:40 -08:00
2e30f1231b
The docs suggest the Next method returns a bool, but that's not the case (`Entry` is an int). ``` // Next advances the parser to the next sample. It returns false if no // more samples were read or an error occurred. Next() (Entry, error) ``` The docs were first added ind80a3de235in 2017. Back then the signature was indeed `func (p *Parser) Next() bool`. But then it got refactored in76a4a46cb0and the signature changed with it, yet docs stayed the same - and eventually made their way into the `Parser` interface. However, the Protobuf parser does have the right wording:5de2df752f``` // Next advances the parser to the next "sample" (emulating the behavior of a // text format parser). It returns (EntryInvalid, io.EOF) if no samples were // read. ``` Changing all other implementations (and the interface itself) to match this doc. Signed-off-by: Ondrej Kokes <ondrej.kokes@gmail.com>
114 lines
4.3 KiB
Go
114 lines
4.3 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 textparse
|
|
|
|
import (
|
|
"mime"
|
|
|
|
"github.com/prometheus/common/model"
|
|
|
|
"github.com/prometheus/prometheus/model/exemplar"
|
|
"github.com/prometheus/prometheus/model/histogram"
|
|
"github.com/prometheus/prometheus/model/labels"
|
|
)
|
|
|
|
// Parser parses samples from a byte slice of samples in the official
|
|
// Prometheus and OpenMetrics text exposition formats.
|
|
type Parser interface {
|
|
// Series returns the bytes of a series with a simple float64 as a
|
|
// value, the timestamp if set, and the value of the current sample.
|
|
Series() ([]byte, *int64, float64)
|
|
|
|
// Histogram returns the bytes of a series with a sparse histogram as a
|
|
// value, the timestamp if set, and the histogram in the current sample.
|
|
// Depending on the parsed input, the function returns an (integer) Histogram
|
|
// or a FloatHistogram, with the respective other return value being nil.
|
|
Histogram() ([]byte, *int64, *histogram.Histogram, *histogram.FloatHistogram)
|
|
|
|
// Help returns the metric name and help text in the current entry.
|
|
// Must only be called after Next returned a help entry.
|
|
// The returned byte slices become invalid after the next call to Next.
|
|
Help() ([]byte, []byte)
|
|
|
|
// Type returns the metric name and type in the current entry.
|
|
// Must only be called after Next returned a type entry.
|
|
// The returned byte slices become invalid after the next call to Next.
|
|
Type() ([]byte, model.MetricType)
|
|
|
|
// Unit returns the metric name and unit in the current entry.
|
|
// Must only be called after Next returned a unit entry.
|
|
// The returned byte slices become invalid after the next call to Next.
|
|
Unit() ([]byte, []byte)
|
|
|
|
// Comment returns the text of the current comment.
|
|
// Must only be called after Next returned a comment entry.
|
|
// The returned byte slice becomes invalid after the next call to Next.
|
|
Comment() []byte
|
|
|
|
// Metric writes the labels of the current sample into the passed labels.
|
|
// It returns the string from which the metric was parsed.
|
|
Metric(l *labels.Labels) string
|
|
|
|
// Exemplar writes the exemplar of the current sample into the passed
|
|
// exemplar. It can be called repeatedly to retrieve multiple exemplars
|
|
// for the same sample. It returns false once all exemplars are
|
|
// retrieved (including the case where no exemplars exist at all).
|
|
Exemplar(l *exemplar.Exemplar) bool
|
|
|
|
// CreatedTimestamp returns the created timestamp (in milliseconds) for the
|
|
// current sample. It returns nil if it is unknown e.g. if it wasn't set,
|
|
// if the scrape protocol or metric type does not support created timestamps.
|
|
CreatedTimestamp() *int64
|
|
|
|
// Next advances the parser to the next sample.
|
|
// It returns (EntryInvalid, io.EOF) if no samples were read.
|
|
Next() (Entry, error)
|
|
}
|
|
|
|
// New returns a new parser of the byte slice.
|
|
//
|
|
// This function always returns a valid parser, but might additionally
|
|
// return an error if the content type cannot be parsed.
|
|
func New(b []byte, contentType string, parseClassicHistograms bool, st *labels.SymbolTable) (Parser, error) {
|
|
if contentType == "" {
|
|
return NewPromParser(b, st), nil
|
|
}
|
|
|
|
mediaType, _, err := mime.ParseMediaType(contentType)
|
|
if err != nil {
|
|
return NewPromParser(b, st), err
|
|
}
|
|
switch mediaType {
|
|
case "application/openmetrics-text":
|
|
return NewOpenMetricsParser(b, st), nil
|
|
case "application/vnd.google.protobuf":
|
|
return NewProtobufParser(b, parseClassicHistograms, st), nil
|
|
default:
|
|
return NewPromParser(b, st), nil
|
|
}
|
|
}
|
|
|
|
// Entry represents the type of a parsed entry.
|
|
type Entry int
|
|
|
|
const (
|
|
EntryInvalid Entry = -1
|
|
EntryType Entry = 0
|
|
EntryHelp Entry = 1
|
|
EntrySeries Entry = 2 // A series with a simple float64 as value.
|
|
EntryComment Entry = 3
|
|
EntryUnit Entry = 4
|
|
EntryHistogram Entry = 5 // A series with a native histogram as a value.
|
|
)
|