1  // Copyright 2015 The Prometheus Authors
 2  // Licensed under the Apache License, Version 2.0 (the "License");
 3  // you may not use this file except in compliance with the License.
 4  // You may obtain a copy of the License at
 5  //
 6  // http://www.apache.org/licenses/LICENSE-2.0
 7  //
 8  // Unless required by applicable law or agreed to in writing, software
 9  // distributed under the License is distributed on an "AS IS" BASIS,
10  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11  // See the License for the specific language governing permissions and
12  // limitations under the License.
13  
14  // Package expfmt contains tools for reading and writing Prometheus metrics.
15  package expfmt
16  
17  // Format specifies the HTTP content type of the different wire protocols.
18  type Format string
19  
20  // Constants to assemble the Content-Type values for the different wire protocols.
21  const (
22  	TextVersion   = "0.0.4"
23  	ProtoType     = `application/vnd.google.protobuf`
24  	ProtoProtocol = `io.prometheus.client.MetricFamily`
25  	ProtoFmt      = ProtoType + "; proto=" + ProtoProtocol + ";"
26  
27  	// The Content-Type values for the different wire protocols.
28  	FmtUnknown      Format = `<unknown>`
29  	FmtText         Format = `text/plain; version=` + TextVersion + `; charset=utf-8`
30  	FmtProtoDelim   Format = ProtoFmt + ` encoding=delimited`
31  	FmtProtoText    Format = ProtoFmt + ` encoding=text`
32  	FmtProtoCompact Format = ProtoFmt + ` encoding=compact-text`
33  )
34  
35  const (
36  	hdrContentType = "Content-Type"
37  	hdrAccept      = "Accept"
38  )