gopl.io/ch7/http3a/main.go

55 lines
1.2 KiB
Go

// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
// See page 195.
// Http3a is an e-commerce server that registers the /list and /price
// endpoints by calling (*http.ServeMux).HandleFunc.
package main
import (
"fmt"
"log"
"net/http"
)
func main() {
db := database{"shoes": 50, "socks": 5}
mux := http.NewServeMux()
//!+main
mux.HandleFunc("/list", db.list)
mux.HandleFunc("/price", db.price)
//!-main
log.Fatal(http.ListenAndServe("localhost:8000", mux))
}
type database map[string]int
func (db database) list(w http.ResponseWriter, req *http.Request) {
for item, price := range db {
fmt.Fprintf(w, "%s: $%d\n", item, price)
}
}
func (db database) price(w http.ResponseWriter, req *http.Request) {
item := req.URL.Query().Get("item")
if price, ok := db[item]; ok {
fmt.Fprintf(w, "$%d\n", price)
} else {
w.WriteHeader(http.StatusNotFound) // 404
fmt.Fprintf(w, "no such item: %q\n", item)
}
}
/*
//!+handlerfunc
package http
type HandlerFunc func(w ResponseWriter, r *Request)
func (f HandlerFunc) ServeHTTP(w ResponseWriter, r *Request) {
f(w, r)
}
//!-handlerfunc
*/