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
|
// Package errdata helps with associating some data to error classes
package errdata
import (
"sync"
"github.com/zeebo/errs"
)
// registry is a concurrent map[key]interface{}. we use this because it is
// expected to be frequently read, with a one time initial set of writes.
var registry sync.Map
// key is the type of keys for the registry map.
type key struct {
class *errs.Class
key interface{}
}
// makeKey is a helper to create a key for the registry map.
func makeKey(class *errs.Class, k interface{}) key {
return key{
class: class,
key: k,
}
}
// Set associates the value for the given key and class. Errors wrapped by the
// class will return the value in the call to Get for the key.
func Set(class *errs.Class, key interface{}, value interface{}) {
registry.Store(makeKey(class, key), value)
}
// Get returns the value associated to the key for the error if any of the
// classes the error is part of have a value associated for that key.
func Get(err error, key interface{}) interface{} {
for _, class := range errs.Classes(err) {
value, ok := registry.Load(makeKey(class, key))
if ok {
return value
}
}
return nil
}
|
