-
Notifications
You must be signed in to change notification settings - Fork 285
/
recovery.go
163 lines (150 loc) · 4.26 KB
/
recovery.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
// Copyright 2013 Martini Authors
// Copyright 2014 The Macaron Authors
//
// Licensed under the Apache License, Version 2.0 (the "License"): you may
// not use this file except in compliance with the License. You may obtain
// a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations
// under the License.
package macaron
import (
"bytes"
"fmt"
"log"
"net/http"
"os"
"runtime"
"github.com/go-macaron/inject"
)
const (
panicHtml = `<html>
<head><title>PANIC: %s</title>
<meta charset="utf-8" />
<style type="text/css">
html, body {
font-family: "Roboto", sans-serif;
color: #333333;
background-color: #ea5343;
margin: 0px;
}
h1 {
color: #d04526;
background-color: #ffffff;
padding: 20px;
border-bottom: 1px dashed #2b3848;
}
pre {
margin: 20px;
padding: 20px;
border: 2px solid #2b3848;
background-color: #ffffff;
white-space: pre-wrap; /* css-3 */
white-space: -moz-pre-wrap; /* Mozilla, since 1999 */
white-space: -pre-wrap; /* Opera 4-6 */
white-space: -o-pre-wrap; /* Opera 7 */
word-wrap: break-word; /* Internet Explorer 5.5+ */
}
</style>
</head><body>
<h1>PANIC</h1>
<pre style="font-weight: bold;">%s</pre>
<pre>%s</pre>
</body>
</html>`
)
var (
dunno = []byte("???")
centerDot = []byte("·")
dot = []byte(".")
slash = []byte("/")
)
// stack returns a nicely formated stack frame, skipping skip frames
func stack(skip int) []byte {
buf := new(bytes.Buffer) // the returned data
// As we loop, we open files and read them. These variables record the currently
// loaded file.
var lines [][]byte
var lastFile string
for i := skip; ; i++ { // Skip the expected number of frames
pc, file, line, ok := runtime.Caller(i)
if !ok {
break
}
// Print this much at least. If we can't find the source, it won't show.
fmt.Fprintf(buf, "%s:%d (0x%x)\n", file, line, pc)
if file != lastFile {
data, err := os.ReadFile(file)
if err != nil {
continue
}
lines = bytes.Split(data, []byte{'\n'})
lastFile = file
}
fmt.Fprintf(buf, "\t%s: %s\n", function(pc), source(lines, line))
}
return buf.Bytes()
}
// source returns a space-trimmed slice of the n'th line.
func source(lines [][]byte, n int) []byte {
n-- // in stack trace, lines are 1-indexed but our array is 0-indexed
if n < 0 || n >= len(lines) {
return dunno
}
return bytes.TrimSpace(lines[n])
}
// function returns, if possible, the name of the function containing the PC.
func function(pc uintptr) []byte {
fn := runtime.FuncForPC(pc)
if fn == nil {
return dunno
}
name := []byte(fn.Name())
// The name includes the path name to the package, which is unnecessary
// since the file name is already included. Plus, it has center dots.
// That is, we see
// runtime/debug.*T·ptrmethod
// and want
// *T.ptrmethod
// Also the package path might contains dot (e.g. code.google.com/...),
// so first eliminate the path prefix
if lastslash := bytes.LastIndex(name, slash); lastslash >= 0 {
name = name[lastslash+1:]
}
if period := bytes.Index(name, dot); period >= 0 {
name = name[period+1:]
}
name = bytes.Replace(name, centerDot, dot, -1)
return name
}
// Recovery returns a middleware that recovers from any panics and writes a 500 if there was one.
// While Martini is in development mode, Recovery will also output the panic as HTML.
func Recovery() Handler {
return func(c *Context, log *log.Logger) {
defer func() {
if err := recover(); err != nil {
stack := stack(3)
log.Printf("PANIC: %s\n%s", err, stack)
// Lookup the current responsewriter
val := c.GetVal(inject.InterfaceOf((*http.ResponseWriter)(nil)))
res := val.Interface().(http.ResponseWriter)
// respond with panic message while in development mode
var body []byte
if Env == DEV {
res.Header().Set("Content-Type", "text/html")
body = []byte(fmt.Sprintf(panicHtml, err, err, stack))
}
res.WriteHeader(http.StatusInternalServerError)
if nil != body {
_, _ = res.Write(body)
}
}
}()
c.Next()
}
}