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
5package 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
12import (
13	"fmt"
14	"html/template"
15	"net/http"
16	"slices"
17	"strings"
18)
19
20const debugText = `<html>
21	<body>
22	<title>Services</title>
23	{{range .}}
24	<hr>
25	Service {{.Name}}
26	<hr>
27		<table>
28		<th align=center>Method</th><th align=center>Calls</th>
29		{{range .Method}}
30			<tr>
31			<td align=left font=fixed>{{.Name}}({{.Type.ArgType}}, {{.Type.ReplyType}}) error</td>
32			<td align=center>{{.Type.NumCalls}}</td>
33			</tr>
34		{{end}}
35		</table>
36	{{end}}
37	</body>
38	</html>`
39
40var debug = template.Must(template.New("RPC debug").Parse(debugText))
41
42// If set, print log statements for internal and I/O errors.
43var debugLog = false
44
45type debugMethod struct {
46	Type *methodType
47	Name string
48}
49
50type methodArray []debugMethod
51
52type debugService struct {
53	Service *service
54	Name    string
55	Method  []debugMethod
56}
57
58type serviceArray []debugService
59
60func (s serviceArray) Len() int           { return len(s) }
61func (s serviceArray) Less(i, j int) bool { return s[i].Name < s[j].Name }
62func (s serviceArray) Swap(i, j int)      { s[i], s[j] = s[j], s[i] }
63
64func (m methodArray) Len() int           { return len(m) }
65func (m methodArray) Less(i, j int) bool { return m[i].Name < m[j].Name }
66func (m methodArray) Swap(i, j int)      { m[i], m[j] = m[j], m[i] }
67
68type debugHTTP struct {
69	*Server
70}
71
72// Runs at /debug/rpc
73func (server debugHTTP) ServeHTTP(w http.ResponseWriter, req *http.Request) {
74	// Build a sorted version of the data.
75	var services serviceArray
76	server.serviceMap.Range(func(snamei, svci any) bool {
77		svc := svci.(*service)
78		ds := debugService{svc, snamei.(string), make([]debugMethod, 0, len(svc.method))}
79		for mname, method := range svc.method {
80			ds.Method = append(ds.Method, debugMethod{method, mname})
81		}
82		slices.SortFunc(ds.Method, func(a, b debugMethod) int {
83			return strings.Compare(a.Name, b.Name)
84		})
85		services = append(services, ds)
86		return true
87	})
88	slices.SortFunc(services, func(a, b debugService) int {
89		return strings.Compare(a.Name, b.Name)
90	})
91	err := debug.Execute(w, services)
92	if err != nil {
93		fmt.Fprintln(w, "rpc: error executing template:", err.Error())
94	}
95}
96