libgo/go/net/rpc/debug.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 package rpc
   6
   7 /*
   8         Some HTML presented at http://machine:port/debug/rpc
   9         Lists services, their methods, and some statistics, still rudimentary.
  10 */
  11
  12 import (
  13         "fmt"
  14         "html/template"
  15         "net/http"
  16         "sort"
  17 )
  18
  19 const debugText = `<html>
  20         <body>
  21         <title>Services</title>
  22         {{range .}}
  23         <hr>
  24         Service {{.Name}}
  25         <hr>
  26                 <table>
  27                 <th align=center>Method</th><th align=center>Calls</th>
  28                 {{range .Method}}
  29                         <tr>
  30                         <td align=left font=fixed>{{.Name}}({{.Type.ArgType}}, {{.Type.ReplyType}}) error</td>
  31                         <td align=center>{{.Type.NumCalls}}</td>
  32                         </tr>
  33                 {{end}}
  34                 </table>
  35         {{end}}
  36         </body>
  37         </html>`
  38
  39 var debug = template.Must(template.New("RPC debug").Parse(debugText))
  40
  41 // If set, print log statements for internal and I/O errors.
  42 var debugLog = false
  43
  44 type debugMethod struct {
  45         Type *methodType
  46         Name string
  47 }
  48
  49 type methodArray []debugMethod
  50
  51 type debugService struct {
  52         Service *service
  53         Name    string
  54         Method  methodArray
  55 }
  56
  57 type serviceArray []debugService
  58
  59 func (s serviceArray) Len() int           { return len(s) }
  60 func (s serviceArray) Less(i, j int) bool { return s[i].Name < s[j].Name }
  61 func (s serviceArray) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
  62
  63 func (m methodArray) Len() int           { return len(m) }
  64 func (m methodArray) Less(i, j int) bool { return m[i].Name < m[j].Name }
  65 func (m methodArray) Swap(i, j int)      { m[i], m[j] = m[j], m[i] }
  66
  67 type debugHTTP struct {
  68         *Server
  69 }
  70
  71 // Runs at /debug/rpc
  72 func (server debugHTTP) ServeHTTP(w http.ResponseWriter, req *http.Request) {
  73         // Build a sorted version of the data.
  74         var services serviceArray
  75         server.serviceMap.Range(func(snamei, svci interface{}) bool {
  76                 svc := svci.(*service)
  77                 ds := debugService{svc, snamei.(string), make(methodArray, 0, len(svc.method))}
  78                 for mname, method := range svc.method {
  79                         ds.Method = append(ds.Method, debugMethod{method, mname})
  80                 }
  81                 sort.Sort(ds.Method)
  82                 services = append(services, ds)
  83                 return true
  84         })
  85         sort.Sort(services)
  86         err := debug.Execute(w, services)
  87         if err != nil {
  88                 fmt.Fprintln(w, "rpc: error executing template:", err.Error())
  89         }
  90 }