Mainflux.mainflux/pkg/messaging/mqtt/publisher.go

51 lines
1.0 KiB
Go

// Copyright (c) Mainflux
// SPDX-License-Identifier: Apache-2.0
package mqtt
import (
"errors"
"time"
mqtt "github.com/eclipse/paho.mqtt.golang"
"github.com/mainflux/mainflux/pkg/messaging"
)
var _ messaging.Publisher = (*publisher)(nil)
var errPublishTimeout = errors.New("failed to publish due to timeout reached")
type publisher struct {
client mqtt.Client
timeout time.Duration
}
// NewPublisher returns a new MQTT message publisher.
func NewPublisher(address string, timeout time.Duration) (messaging.Publisher, error) {
client, err := newClient(address, timeout)
if err != nil {
return nil, err
}
ret := publisher{
client: client,
timeout: timeout,
}
return ret, nil
}
func (pub publisher) Publish(topic string, msg messaging.Message) error {
token := pub.client.Publish(topic, qos, false, msg.Payload)
if token.Error() != nil {
return token.Error()
}
ok := token.WaitTimeout(pub.timeout)
if ok && token.Error() != nil {
return token.Error()
}
if !ok {
return errPublishTimeout
}
return nil
}