-
Notifications
You must be signed in to change notification settings - Fork 302
/
redis.go
79 lines (67 loc) · 2.23 KB
/
redis.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
// 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"
"go.thethings.network/lorawan-stack/v3/pkg/errors"
ttnredis "go.thethings.network/lorawan-stack/v3/pkg/redis"
"go.thethings.network/lorawan-stack/v3/pkg/ttnpb"
"go.thethings.network/lorawan-stack/v3/pkg/unique"
)
// PubSub is a Redis-based upstream traffic Pub/Sub.
type PubSub struct {
Redis *ttnredis.Client
}
func (ps PubSub) uidUplinkKey(uid string) string {
return ps.Redis.Key("uid", uid, "uplinks")
}
// Publish publishes the uplink to Pub/Sub.
func (ps PubSub) Publish(ctx context.Context, up *ttnpb.ApplicationUp) error {
s, err := ttnredis.MarshalProto(up)
if err != nil {
return err
}
uid := unique.ID(ctx, up.ApplicationIdentifiers)
ch := ps.uidUplinkKey(uid)
if err = ps.Redis.Publish(ctx, ch, s).Err(); err != nil {
return ttnredis.ConvertError(err)
}
return nil
}
var errChannelClosed = errors.DefineResourceExhausted("channel_closed", "channel closed")
// Subscribe subscribes to the traffic of the provided application and processes it using the handler.
func (ps PubSub) Subscribe(ctx context.Context, ids ttnpb.ApplicationIdentifiers, handler func(context.Context, *ttnpb.ApplicationUp) error) error {
uid := unique.ID(ctx, ids)
ch := ps.uidUplinkKey(uid)
sub := ps.Redis.Subscribe(ctx, ch)
defer sub.Close()
msgs := sub.Channel()
for {
select {
case <-ctx.Done():
return ctx.Err()
case msg, ok := <-msgs:
if !ok {
return errChannelClosed.New()
}
up := &ttnpb.ApplicationUp{}
if err := ttnredis.UnmarshalProto(msg.Payload, up); err != nil {
return err
}
if err := handler(ctx, up); err != nil {
return err
}
}
}
}