rss/time.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
package rss
import (
"fmt"
"strings"
"time"
)
// TimeLayoutsLoadLocation are time layouts
// which do not contain the location as a fixed
// constant. Instead of -0700, they use MST.
// Golang does not load the timezone by default,
// which means parseTime calls
// `time.LoadLocation(t.Location().String())`
// and then applies the offset returned by
// LoadLocation to the result.
var TimeLayoutsLoadLocation = []string{
"Mon, 2 Jan 2006 15:04:05 MST",
"Mon, 2 Jan 06 15:04:05 MST",
"2 Jan 2006 15:04:05 MST",
"2 Jan 06 15:04:05 MST",
"Jan 2, 2006 15:04 PM MST",
"Jan 2, 06 15:04 PM MST",
time.RFC1123,
time.RFC850,
time.RFC822,
}
// TimeLayouts is contains a list of time.Parse() layouts that are used in
// attempts to convert item.Date and item.PubDate string to time.Time values.
// The layouts are attempted in ascending order until either time.Parse()
// does not return an error or all layouts are attempted.
var TimeLayouts = []string{
"Mon, 2 Jan 2006 15:04:05 Z",
"Mon, 2 Jan 2006 15:04:05",
"Mon, 2 Jan 2006 15:04:05 -0700",
"Mon, 2 Jan 06 15:04:05 -0700",
"Mon, 2 Jan 06 15:04:05",
"2 Jan 2006 15:04:05 -0700",
"2 Jan 2006 15:04:05",
"2 Jan 06 15:04:05 -0700",
"2006-01-02 15:04:05 -0700",
"2006-01-02 15:04:05",
time.ANSIC,
time.UnixDate,
time.RubyDate,
time.RFC822Z,
time.RFC1123Z,
time.RFC3339,
time.RFC3339Nano,
// Not some common time zones. While they are odd,
// they can occur but we should only check
// them last (to slightly improve runtime).
// We also always use the offset, because the
// texual representation can be ambiguous.
// For example, PST can have different rules
// in different locals:
// https://news.ycombinator.com/item?id=10199812
"2 Jan 2006 15:04:05 -0700 MST",
"2 Jan 2006 15:04:05 MST -0700",
"Mon, 2 Jan 2006 15:04:05 MST -0700",
"Mon, 2 Jan 2006 15:04:05 -0700 MST",
"2 Jan 06 15:04:05 -0700 MST",
"2 Jan 06 15:04:05 MST -0700",
"Jan 2, 2006 15:04 PM -0700 MST",
"Jan 2, 2006 15:04 PM MST -0700",
"Jan 2, 06 15:04 PM MST -0700",
"Jan 2, 06 15:04 PM -0700 MST",
}
func parseTime(s string) (time.Time, error) {
s = strings.TrimSpace(s)
var e error
var t time.Time
for _, layout := range TimeLayouts {
t, e = time.Parse(layout, s)
if e == nil {
return t, nil
}
}
for _, layout := range TimeLayoutsLoadLocation {
t, e = time.Parse(layout, s)
if e != nil {
continue
}
// In case LoadLocation returns an error
// we want to return the time and error
// as is. LoadLocation commonly returns an
// error if tzinfo is not installed.
// This often happens when running go applications
// inside an alpine docker container.
loc, err := time.LoadLocation(t.Location().String())
if err != nil {
if debug {
fmt.Printf("[w] could not load timezone: %q\n", e)
}
return t, err
}
t, e = time.ParseInLocation(layout, s, loc)
if e == nil {
return t, nil
}
}
return time.Time{}, e
}