-
Notifications
You must be signed in to change notification settings - Fork 0
/
dataloader.go
50 lines (41 loc) · 1.3 KB
/
dataloader.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
package main
import (
"encoding/json"
"errors"
"fmt"
"google.golang.org/protobuf/proto"
)
type DataLoader struct {
unmarshaler func([]byte) error
loader func() error
}
func (l *DataLoader) Load(data []byte) (err error) {
if err = l.unmarshaler(data); err == nil {
err = l.loader()
}
return
}
func NewDataLoader(unmarshaler func([]byte) error, callback func() error) *DataLoader {
return &DataLoader{unmarshaler: unmarshaler, loader: callback}
}
func NewProtoLoader(into proto.Message, callback func() error) *DataLoader {
return NewDataLoader(func(data []byte) error { return proto.Unmarshal(data, into) }, callback)
}
func NewJSONLoader(into interface{}, callback func() error) *DataLoader {
return NewDataLoader(func(data []byte) error { return json.Unmarshal(data, into) }, callback)
}
func NewTypedDataLoader(name string, storage interface{}, callback func() error) (*DataLoader, error) {
if storage == nil {
return nil, errors.New("nil storage for loader")
}
switch name {
case "proto":
return NewProtoLoader(storage.(proto.Message), callback), nil
case "gom":
return NewProtoLoader(storage.(proto.Message), callback), nil
case "json":
return NewJSONLoader(storage, callback), nil
default:
return nil, fmt.Errorf("%w: unrecognized loader type: %s", ErrUnknownEntity, name)
}
}