databag/net/server/internal/api_getChannelSubjectField.go

package databag

import (
  "time"
  "bytes"
  "strings"
  "net/http"
  "encoding/base64"
  "github.com/gorilla/mux"
  "github.com/valyala/fastjson"
)

func GetChannelSubjectField(w http.ResponseWriter, r *http.Request) {

  // scan parameters
  params := mux.Vars(r)
  field := params["field"]
  elements := strings.Split(field, ".")

  // get channel stlot
  channelSlot, _, err, code := getChannelSlot(r, false)
  if err != nil {
    ErrResponse(w, code, err)
    return
  }

  // decode data
  strData := fastjson.GetString([]byte(channelSlot.Channel.Data), elements...)
  binData, err := base64.StdEncoding.DecodeString(strData)
  if err != nil {
    ErrResponse(w, http.StatusNotFound, err)
    return
  }

  // response with content
  http.ServeContent(w, r, field, time.Unix(channelSlot.Channel.Updated, 0), bytes.NewReader(binData))
}