hello.go

package main
 
import (
	"encoding/json"
	"fmt"
	"io/ioutil"
	"net/http"
	"regexp"
	"strings"
)
 
type User struct {
	Name string `json:"name"`
}
 
func main() {
	fmt.Println("Starting")
	var helloRE = regexp.MustCompile(`/hello/(\d)`)
 
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 
		if helloRE.MatchString(r.RequestURI) {
			var id = helloRE.FindStringSubmatch(r.RequestURI)[1]
			res, err := http.Get("http://jsonplaceholder.typicode.com/users/" + id)
			if err != nil {
				fmt.Fprintf(w, "Oops: %s", err)
			}
			jsonStream, err := ioutil.ReadAll(res.Body)
			if err != nil {
				fmt.Fprintf(w, "Oops: %s", err)
			}
			dec := json.NewDecoder(strings.NewReader(string(jsonStream)))
			var user User
			if err := dec.Decode(&user); err != nil {
				fmt.Fprintf(w, "Oops: %s", err)
			}
			fmt.Fprintf(w, "The name for id %s is %s", id, user.Name)
		} else {
			w.WriteHeader(http.StatusNotFound)
			fmt.Fprintf(w, "Usage: /hello/id where id = single digit")
		}
	})
	fmt.Println(http.ListenAndServe(":6060", nil))
}