-
Notifications
You must be signed in to change notification settings - Fork 299
/
pagination.go
56 lines (48 loc) · 1.78 KB
/
pagination.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
// Copyright © 2019 The Things Network Foundation, The Things Industries B.V.
//
// 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 redis
import (
"context"
)
type paginationOptionsKeyType struct{}
var paginationOptionsKey paginationOptionsKeyType
type paginationOptions struct {
limit int64
offset int64
total *int64
}
// NewContextWithPagination instructs the store to paginate the results.
func NewContextWithPagination(ctx context.Context, limit, page int64, total *int64) context.Context {
if page == 0 {
page = 1
}
return context.WithValue(ctx, paginationOptionsKey, paginationOptions{
limit: limit,
offset: (page - 1) * limit,
total: total,
})
}
// SetPaginationTotal sets the total number of results inside the paginated context, if it was not set already.
func SetPaginationTotal(ctx context.Context, total int64) {
if opts, ok := ctx.Value(paginationOptionsKey).(paginationOptions); ok && opts.total != nil && *opts.total == 0 {
*opts.total = total
}
}
// PaginationLimitAndOffsetFromContext returns the pagination limit and the offset if they are present.
func PaginationLimitAndOffsetFromContext(ctx context.Context) (limit, offset int64) {
if opts, ok := ctx.Value(paginationOptionsKey).(paginationOptions); ok {
return opts.limit, opts.offset
}
return
}