hunk.code_window: 	"github.com/mattermost/platform/einterfaces"
   	"github.com/mattermost/platform/utils"
   )
  
hunk.labels: add keep keep keep
hunk.after_edit: 	"github.com/mattermost/platform/model"
  
hunk.file_path: app/elasticsearch.go
hunk.type: add
file: // Copyright 2015 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 expfmt
  
  import (
  	"fmt"
  	"io"
  	"net/http"
  
  	"github.com/golang/protobuf/proto"
  	"github.com/matttproud/golang_protobuf_extensions/pbutil"
  	"github.com/prometheus/common/internal/bitbucket.org/ww/goautoneg"
  
  	dto "github.com/prometheus/client_model/go"
  )
  
  // Encoder types encode metric families into an underlying wire protocol.
  type Encoder interface {
  	Encode(*dto.MetricFamily) error
  }
  
  type encoder func(*dto.MetricFamily) error
  
  func (e encoder) Encode(v *dto.MetricFamily) error {
  	return e(v)
  }
  
  // Negotiate returns the Content-Type based on the given Accept header.
  // If no appropriate accepted type is found, FmtText is returned.
  func Negotiate(h http.Header) Format {
  	for _, ac := range goautoneg.ParseAccept(h.Get(hdrAccept)) {
  		// Check for protocol buffer
  		if ac.Type+"/"+ac.SubType == ProtoType && ac.Params["proto"] == ProtoProtocol {
  			switch ac.Params["encoding"] {
  			case "delimited":
  				return FmtProtoDelim
  			case "text":
  				return FmtProtoText
  			case "compact-text":
  				return FmtProtoCompact
  			}
  		}
  		// Check for text format.
  		ver := ac.Params["version"]
  		if ac.Type == "text" && ac.SubType == "plain" && (ver == TextVersion || ver == "") {
  			return FmtText
  		}
  	}
  	return FmtText
  }
  
  // NewEncoder returns a new encoder based on content type negotiation.
  func NewEncoder(w io.Writer, format Format) Encoder {
  	switch format {
  	case FmtProtoDelim:
  		return encoder(func(v *dto.MetricFamily) error {
  			_, err := pbutil.WriteDelimited(w, v)
  			return err
  		})
  	case FmtProtoCompact:
  		return encoder(func(v *dto.MetricFamily) error {
  			_, err := fmt.Fprintln(w, v.String())
  			return err
  		})
  	case FmtProtoText:
  		return encoder(func(v *dto.MetricFamily) error {
  			_, err := fmt.Fprintln(w, proto.MarshalTextString(v))
  			return err
  		})
  	case FmtText:
  		return encoder(func(v *dto.MetricFamily) error {
  			_, err := MetricFamilyToText(w, v)
  			return err
  		})
  	}
  	panic("expfmt.NewEncoder: unknown format")
  }
  