/
callback.go
92 lines (64 loc) · 1.56 KB
/
callback.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
package hooks
import (
"reflect"
"cyberpull.com/gotk/errors"
)
type Callback any
func toCallback(fn Callback) (value reflect.Value, err error) {
tmpValue := reflect.ValueOf(fn)
if tmpValue.Kind() != reflect.Func {
err = errors.Newf(`"%s" is not a function`, 500, tmpValue.Type().Name())
return
}
value = tmpValue
return
}
func toActionCallback(fn Callback) (value reflect.Value, err error) {
tmpValue, err := toCallback(fn)
if err != nil {
return
}
fnType := tmpValue.Type()
if fnType.NumOut() != 1 {
err = errors.New("Callback function must have only 1 return value")
return
}
errType := reflect.TypeOf((*error)(nil)).Elem()
if !fnType.Out(0).Implements(errType) {
err = errors.New(`Callback's return value must be an "error".`, 500)
return
}
value = tmpValue
return
}
func toFilterCallback(fn Callback) (value reflect.Value, err error) {
tmpValue, err := toCallback(fn)
if err != nil {
return
}
fnType := tmpValue.Type()
if fnType.NumOut() != 2 {
err = errors.New("Callback function must have 2 return values")
return
}
errType := reflect.TypeOf((*error)(nil)).Elem()
if !fnType.Out(1).Implements(errType) {
err = errors.New(`Callback's last return value must be an "error".`, 500)
return
}
value = tmpValue
return
}
func call(fn reflect.Value, args ...any) (value []reflect.Value, err error) {
fargs := make([]reflect.Value, len(args))
for i, arg := range args {
fargs[i] = reflect.ValueOf(arg)
}
defer func() {
if r := recover(); r != nil {
err = errors.From(r)
}
}()
value = fn.Call(fargs)
return
}