telegraf/plugins/outputs/mqtt/mqtt.go

199 lines
4.2 KiB
Go

package mqtt
import (
"fmt"
"strings"
"sync"
paho "git.eclipse.org/gitroot/paho/org.eclipse.paho.mqtt.golang.git"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/internal"
"github.com/influxdata/telegraf/plugins/outputs"
"github.com/influxdata/telegraf/plugins/serializers"
)
var sampleConfig = `
servers = ["localhost:1883"] # required.
### MQTT outputs send metrics to this topic format
### "<topic_prefix>/<hostname>/<pluginname>/"
### ex: prefix/host/web01.example.com/mem
topic_prefix = "telegraf"
### username and password to connect MQTT server.
# username = "telegraf"
# password = "metricsmetricsmetricsmetrics"
### Optional SSL Config
# ssl_ca = "/etc/telegraf/ca.pem"
# ssl_cert = "/etc/telegraf/cert.pem"
# ssl_key = "/etc/telegraf/key.pem"
### Use SSL but skip chain & host verification
# insecure_skip_verify = false
### Data format to output. This can be "influx" or "graphite"
### Each data format has it's own unique set of configuration options, read
### more about them here:
### https://github.com/influxdata/telegraf/blob/master/DATA_FORMATS_OUTPUT.md
data_format = "influx"
`
type MQTT struct {
Servers []string `toml:"servers"`
Username string
Password string
Database string
Timeout internal.Duration
TopicPrefix string
QoS int `toml:"qos"`
// Path to CA file
SSLCA string `toml:"ssl_ca"`
// Path to host cert file
SSLCert string `toml:"ssl_cert"`
// Path to cert key file
SSLKey string `toml:"ssl_key"`
// Use SSL but skip chain & host verification
InsecureSkipVerify bool
client *paho.Client
opts *paho.ClientOptions
serializer serializers.Serializer
sync.Mutex
}
func (m *MQTT) Connect() error {
var err error
m.Lock()
defer m.Unlock()
if m.QoS > 2 || m.QoS < 0 {
return fmt.Errorf("MQTT Output, invalid QoS value: %d", m.QoS)
}
m.opts, err = m.createOpts()
if err != nil {
return err
}
m.client = paho.NewClient(m.opts)
if token := m.client.Connect(); token.Wait() && token.Error() != nil {
return token.Error()
}
return nil
}
func (m *MQTT) SetSerializer(serializer serializers.Serializer) {
m.serializer = serializer
}
func (m *MQTT) Close() error {
if m.client.IsConnected() {
m.client.Disconnect(20)
}
return nil
}
func (m *MQTT) SampleConfig() string {
return sampleConfig
}
func (m *MQTT) Description() string {
return "Configuration for MQTT server to send metrics to"
}
func (m *MQTT) Write(metrics []telegraf.Metric) error {
m.Lock()
defer m.Unlock()
if len(metrics) == 0 {
return nil
}
hostname, ok := metrics[0].Tags()["host"]
if !ok {
hostname = ""
}
for _, metric := range metrics {
var t []string
if m.TopicPrefix != "" {
t = append(t, m.TopicPrefix)
}
if hostname != "" {
t = append(t, hostname)
}
t = append(t, metric.Name())
topic := strings.Join(t, "/")
values, err := m.serializer.Serialize(metric)
if err != nil {
return fmt.Errorf("MQTT Could not serialize metric: %s",
metric.String())
}
for _, value := range values {
err = m.publish(topic, value)
if err != nil {
return fmt.Errorf("Could not write to MQTT server, %s", err)
}
}
}
return nil
}
func (m *MQTT) publish(topic, body string) error {
token := m.client.Publish(topic, byte(m.QoS), false, body)
token.Wait()
if token.Error() != nil {
return token.Error()
}
return nil
}
func (m *MQTT) createOpts() (*paho.ClientOptions, error) {
opts := paho.NewClientOptions()
opts.SetClientID("Telegraf-Output-" + internal.RandomString(5))
tlsCfg, err := internal.GetTLSConfig(
m.SSLCert, m.SSLKey, m.SSLCA, m.InsecureSkipVerify)
if err != nil {
return nil, err
}
scheme := "tcp"
if tlsCfg != nil {
scheme = "ssl"
opts.SetTLSConfig(tlsCfg)
}
user := m.Username
if user == "" {
opts.SetUsername(user)
}
password := m.Password
if password != "" {
opts.SetPassword(password)
}
if len(m.Servers) == 0 {
return opts, fmt.Errorf("could not get host infomations")
}
for _, host := range m.Servers {
server := fmt.Sprintf("%s://%s", scheme, host)
opts.AddBroker(server)
}
opts.SetAutoReconnect(true)
return opts, nil
}
func init() {
outputs.Add("mqtt", func() telegraf.Output {
return &MQTT{}
})
}