49 lines
1.0 KiB
Go
49 lines
1.0 KiB
Go
// Copyright © 2016 Alan A. A. Donovan & Brian W. Kernighan.
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// License: https://creativecommons.org/licenses/by-nc-sa/4.0/
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// See page 192.
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// Http2 is an e-commerce server with /list and /price endpoints.
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package main
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import (
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"fmt"
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"log"
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"net/http"
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)
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func main() {
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db := database{"shoes": 50, "socks": 5}
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log.Fatal(http.ListenAndServe("localhost:8000", db))
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}
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type dollars float32
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func (d dollars) String() string { return fmt.Sprintf("$%.2f", d) }
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type database map[string]dollars
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//!+handler
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func (db database) ServeHTTP(w http.ResponseWriter, req *http.Request) {
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switch req.URL.Path {
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case "/list":
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for item, price := range db {
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fmt.Fprintf(w, "%s: %s\n", item, price)
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}
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case "/price":
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item := req.URL.Query().Get("item")
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price, ok := db[item]
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if !ok {
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w.WriteHeader(http.StatusNotFound) // 404
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fmt.Fprintf(w, "no such item: %q\n", item)
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return
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}
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fmt.Fprintf(w, "%s\n", price)
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default:
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w.WriteHeader(http.StatusNotFound) // 404
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fmt.Fprintf(w, "no such page: %s\n", req.URL)
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}
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}
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//!-handler
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