embedded-5_0-branch/libgo/go/net/http/triv.go

   1 // Copyright 2009 The Go Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style
   3 // license that can be found in the LICENSE file.
   4
   5 // +build ignore
   6
   7 package main
   8
   9 import (
  10         "bytes"
  11         "expvar"
  12         "flag"
  13         "fmt"
  14         "io"
  15         "log"
  16         "net/http"
  17         "os"
  18         "os/exec"
  19         "strconv"
  20         "sync"
  21 )
  22
  23 // hello world, the web server
  24 var helloRequests = expvar.NewInt("hello-requests")
  25
  26 func HelloServer(w http.ResponseWriter, req *http.Request) {
  27         helloRequests.Add(1)
  28         io.WriteString(w, "hello, world!\n")
  29 }
  30
  31 // Simple counter server. POSTing to it will set the value.
  32 type Counter struct {
  33         mu sync.Mutex // protects n
  34         n  int
  35 }
  36
  37 // This makes Counter satisfy the expvar.Var interface, so we can export
  38 // it directly.
  39 func (ctr *Counter) String() string {
  40         ctr.mu.Lock()
  41         defer ctr.mu.Unlock()
  42         return fmt.Sprintf("%d", ctr.n)
  43 }
  44
  45 func (ctr *Counter) ServeHTTP(w http.ResponseWriter, req *http.Request) {
  46         ctr.mu.Lock()
  47         defer ctr.mu.Unlock()
  48         switch req.Method {
  49         case "GET":
  50                 ctr.n++
  51         case "POST":
  52                 buf := new(bytes.Buffer)
  53                 io.Copy(buf, req.Body)
  54                 body := buf.String()
  55                 if n, err := strconv.Atoi(body); err != nil {
  56                         fmt.Fprintf(w, "bad POST: %v\nbody: [%v]\n", err, body)
  57                 } else {
  58                         ctr.n = n
  59                         fmt.Fprint(w, "counter reset\n")
  60                 }
  61         }
  62         fmt.Fprintf(w, "counter = %d\n", ctr.n)
  63 }
  64
  65 // simple flag server
  66 var booleanflag = flag.Bool("boolean", true, "another flag for testing")
  67
  68 func FlagServer(w http.ResponseWriter, req *http.Request) {
  69         w.Header().Set("Content-Type", "text/plain; charset=utf-8")
  70         fmt.Fprint(w, "Flags:\n")
  71         flag.VisitAll(func(f *flag.Flag) {
  72                 if f.Value.String() != f.DefValue {
  73                         fmt.Fprintf(w, "%s = %s [default = %s]\n", f.Name, f.Value.String(), f.DefValue)
  74                 } else {
  75                         fmt.Fprintf(w, "%s = %s\n", f.Name, f.Value.String())
  76                 }
  77         })
  78 }
  79
  80 // simple argument server
  81 func ArgServer(w http.ResponseWriter, req *http.Request) {
  82         for _, s := range os.Args {
  83                 fmt.Fprint(w, s, " ")
  84         }
  85 }
  86
  87 // a channel (just for the fun of it)
  88 type Chan chan int
  89
  90 func ChanCreate() Chan {
  91         c := make(Chan)
  92         go func(c Chan) {
  93                 for x := 0; ; x++ {
  94                         c <- x
  95                 }
  96         }(c)
  97         return c
  98 }
  99
 100 func (ch Chan) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 101         io.WriteString(w, fmt.Sprintf("channel send #%d\n", <-ch))
 102 }
 103
 104 // exec a program, redirecting output
 105 func DateServer(rw http.ResponseWriter, req *http.Request) {
 106         rw.Header().Set("Content-Type", "text/plain; charset=utf-8")
 107
 108         date, err := exec.Command("/bin/date").Output()
 109         if err != nil {
 110                 http.Error(rw, err.Error(), 500)
 111                 return
 112         }
 113         rw.Write(date)
 114 }
 115
 116 func Logger(w http.ResponseWriter, req *http.Request) {
 117         log.Print(req.URL)
 118         http.Error(w, "oops", 404)
 119 }
 120
 121 var webroot = flag.String("root", os.Getenv("HOME"), "web root directory")
 122
 123 func main() {
 124         flag.Parse()
 125
 126         // The counter is published as a variable directly.
 127         ctr := new(Counter)
 128         expvar.Publish("counter", ctr)
 129         http.Handle("/counter", ctr)
 130         http.Handle("/", http.HandlerFunc(Logger))
 131         http.Handle("/go/", http.StripPrefix("/go/", http.FileServer(http.Dir(*webroot))))
 132         http.Handle("/chan", ChanCreate())
 133         http.HandleFunc("/flags", FlagServer)
 134         http.HandleFunc("/args", ArgServer)
 135         http.HandleFunc("/go/hello", HelloServer)
 136         http.HandleFunc("/date", DateServer)
 137         err := http.ListenAndServe(":12345", nil)
 138         if err != nil {
 139                 log.Panicln("ListenAndServe:", err)
 140         }
 141 }