example curl -l http://localhost:8080/example.com/obix/org/lon/@XBureau922/@XLocations/@XLSI/@XSunSensor/@XnvoSunLux_2/$@CSNVT_lux/?name=lux2&format=influx

obix-proxy.go

package main

import (
	"fmt"
	"io/ioutil"
	"net/http"
	"encoding/xml"
	"strconv"
	"time"
)

type ObixValue struct {
	XMLName xml.Name
	Value string `xml:"val,attr"`
}


func handler(w http.ResponseWriter, r *http.Request) {
	resp, err := http.Get("http://" + r.URL.Path[1:])
	if err != nil {
		return
	}
	defer resp.Body.Close()
	body, err := ioutil.ReadAll(resp.Body)
	v := ObixValue{}
	err = xml.Unmarshal(body, &v)

	if err != nil {
		return
	}
	switch(r.URL.Query().Get("format")){
	case "influx":
		w.Header().Set("Content-type","text/plain")
		timestamp := time.Now().UnixNano()

		switch v.XMLName.Local {
		case "int":
			if value, err := strconv.Atoi(v.Value); err == nil {
				fmt.Fprintf(w, "obix %s=%d %d",r.URL.Query().Get("name"),value, timestamp )
			}
		case  "real":
			if value, err := strconv.ParseFloat(v.Value,64); err == nil {
				fmt.Fprintf(w, "obix %s=%f %d",r.URL.Query().Get("name"),value,timestamp )
			}
		default:
			fmt.Fprintf(w, "obix %s=%s %d",r.URL.Query().Get("name"),v.Value,timestamp )
		}
	case "text":
		w.Header().Set("Content-type","text/plain")
		fmt.Fprintf(w, "%s",v.Value )
	default:
		w.Header().Set("Content-type","application/json")
		switch v.XMLName.Local {
		case "int":
			if value, err := strconv.Atoi(v.Value); err == nil {
				fmt.Fprintf(w, "{\"%s\" : %d}",r.URL.Query().Get("name"),value )
			}
		case  "real":
			if value, err := strconv.ParseFloat(v.Value,64); err == nil {
				fmt.Fprintf(w, "{\"%s\" : %f}",r.URL.Query().Get("name"),value )
			}
		default:
			fmt.Fprintf(w, "{\"%s\" : \"%s\"}",r.URL.Query().Get("name"),v.Value )
		}
	}




}

func main() {
	http.HandleFunc("/", handler)
	http.ListenAndServe(":8080", nil)
}