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42 lines
798 B
Go
42 lines
798 B
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 20.
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//!+
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// Server2 is a minimal "echo" and counter server.
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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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"sync"
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)
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var mu sync.Mutex
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var count int
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func main() {
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http.HandleFunc("/", handler)
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http.HandleFunc("/count", counter)
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log.Fatal(http.ListenAndServe("localhost:8000", nil))
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}
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// handler echoes the Path component of the requested URL.
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func handler(w http.ResponseWriter, r *http.Request) {
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mu.Lock()
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count++
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mu.Unlock()
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fmt.Fprintf(w, "URL.Path = %q\n", r.URL.Path)
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}
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// counter echoes the number of calls so far.
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func counter(w http.ResponseWriter, r *http.Request) {
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mu.Lock()
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fmt.Fprintf(w, "Count %d\n", count)
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mu.Unlock()
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}
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//!-
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