Generic configuration exposed over HTTP

configserver.go

package main

import (
	"fmt"
	"net/http"
	"os"
	"reflect"
	"strings"
)

type ConfigServer struct {
	values map[string]string
}

func (c *ConfigServer) ServeHTTP(w http.ResponseWriter, r *http.Request) {
	fmt.Fprint(w, c.values)
}

/*
This takes the address of your Config Struct and will try and get environment variable values for each 
public field name. It then returns you a "config server" which you can then mount on to an endpoint 
for debugging
*/
func NewConfigServer(config interface{}) *ConfigServer {
	c := new(ConfigServer)
	c.values = make(map[string]string)

	s := reflect.ValueOf(config).Elem()
	typeOfKeys := s.Type()

	for i := 0; i < s.NumField(); i++ {
		fieldName := typeOfKeys.Field(i).Name
		envValue := os.Getenv(strings.ToUpper(fieldName))
		f := s.Field(i)
		f.SetString(envValue)
		c.values[fieldName] = envValue
	}

	return c

}

/*
This struct can have any number of string fields with different names for your app
*/
type FooFields struct {
	Foo string
	Bar string
}

func main() {
	myConfig := FooFields{}
	server := NewConfigServer(&myConfig)

	fmt.Println(myConfig)
	http.ListenAndServe(":8080", server)
}