telegraf/plugins/inputs/amqp_consumer/amqp_consumer.go

281 lines
6.1 KiB
Go

package amqp_consumer
import (
"fmt"
"log"
"strings"
"sync"
"time"
"github.com/streadway/amqp"
"github.com/influxdata/telegraf"
"github.com/influxdata/telegraf/internal"
"github.com/influxdata/telegraf/plugins/inputs"
"github.com/influxdata/telegraf/plugins/parsers"
)
// AMQPConsumer is the top level struct for this plugin
type AMQPConsumer struct {
URL string
// AMQP exchange
Exchange string
// Queue Name
Queue string
// Binding Key
BindingKey string `toml:"binding_key"`
// Controls how many messages the server will try to keep on the network
// for consumers before receiving delivery acks.
PrefetchCount int
// AMQP Auth method
AuthMethod string
// 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
parser parsers.Parser
conn *amqp.Connection
wg *sync.WaitGroup
}
type externalAuth struct{}
func (a *externalAuth) Mechanism() string {
return "EXTERNAL"
}
func (a *externalAuth) Response() string {
return fmt.Sprintf("\000")
}
const (
DefaultAuthMethod = "PLAIN"
DefaultPrefetchCount = 50
)
func (a *AMQPConsumer) SampleConfig() string {
return `
## AMQP url
url = "amqp://localhost:5672/influxdb"
## AMQP exchange
exchange = "telegraf"
## AMQP queue name
queue = "telegraf"
## Binding Key
binding_key = "#"
## Maximum number of messages server should give to the worker.
prefetch_count = 50
## Auth method. PLAIN and EXTERNAL are supported
## Using EXTERNAL requires enabling the rabbitmq_auth_mechanism_ssl plugin as
## described here: https://www.rabbitmq.com/plugins.html
# auth_method = "PLAIN"
## 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.
## Each data format has it's own unique set of configuration options, read
## more about them here:
## https://github.com/influxdata/telegraf/blob/master/docs/DATA_FORMATS_OUTPUT.md
data_format = "influx"
`
}
func (a *AMQPConsumer) Description() string {
return "AMQP consumer plugin"
}
func (a *AMQPConsumer) SetParser(parser parsers.Parser) {
a.parser = parser
}
// All gathering is done in the Start function
func (a *AMQPConsumer) Gather(_ telegraf.Accumulator) error {
return nil
}
func (a *AMQPConsumer) createConfig() (*amqp.Config, error) {
// make new tls config
tls, err := internal.GetTLSConfig(
a.SSLCert, a.SSLKey, a.SSLCA, a.InsecureSkipVerify)
if err != nil {
return nil, err
}
// parse auth method
var sasl []amqp.Authentication // nil by default
if strings.ToUpper(a.AuthMethod) == "EXTERNAL" {
sasl = []amqp.Authentication{&externalAuth{}}
}
config := amqp.Config{
TLSClientConfig: tls,
SASL: sasl, // if nil, it will be PLAIN
}
return &config, nil
}
// Start satisfies the telegraf.ServiceInput interface
func (a *AMQPConsumer) Start(acc telegraf.Accumulator) error {
amqpConf, err := a.createConfig()
if err != nil {
return err
}
msgs, err := a.connect(amqpConf)
if err != nil {
return err
}
a.wg = &sync.WaitGroup{}
a.wg.Add(1)
go a.process(msgs, acc)
go func() {
err := <-a.conn.NotifyClose(make(chan *amqp.Error))
if err == nil {
return
}
log.Printf("I! AMQP consumer connection closed: %s; trying to reconnect", err)
for {
msgs, err := a.connect(amqpConf)
if err != nil {
log.Printf("E! AMQP connection failed: %s", err)
time.Sleep(10 * time.Second)
continue
}
a.wg.Add(1)
go a.process(msgs, acc)
break
}
}()
return nil
}
func (a *AMQPConsumer) connect(amqpConf *amqp.Config) (<-chan amqp.Delivery, error) {
conn, err := amqp.DialConfig(a.URL, *amqpConf)
if err != nil {
return nil, err
}
a.conn = conn
ch, err := conn.Channel()
if err != nil {
return nil, fmt.Errorf("Failed to open a channel: %s", err)
}
err = ch.ExchangeDeclare(
a.Exchange, // name
"topic", // type
true, // durable
false, // auto-deleted
false, // internal
false, // no-wait
nil, // arguments
)
if err != nil {
return nil, fmt.Errorf("Failed to declare an exchange: %s", err)
}
q, err := ch.QueueDeclare(
a.Queue, // queue
true, // durable
false, // delete when unused
false, // exclusive
false, // no-wait
nil, // arguments
)
if err != nil {
return nil, fmt.Errorf("Failed to declare a queue: %s", err)
}
err = ch.QueueBind(
q.Name, // queue
a.BindingKey, // binding-key
a.Exchange, // exchange
false,
nil,
)
if err != nil {
return nil, fmt.Errorf("Failed to bind a queue: %s", err)
}
err = ch.Qos(
a.PrefetchCount,
0, // prefetch-size
false, // global
)
if err != nil {
return nil, fmt.Errorf("Failed to set QoS: %s", err)
}
msgs, err := ch.Consume(
q.Name, // queue
"", // consumer
false, // auto-ack
false, // exclusive
false, // no-local
false, // no-wait
nil, // arguments
)
if err != nil {
return nil, fmt.Errorf("Failed establishing connection to queue: %s", err)
}
log.Println("I! Started AMQP consumer")
return msgs, err
}
// Read messages from queue and add them to the Accumulator
func (a *AMQPConsumer) process(msgs <-chan amqp.Delivery, acc telegraf.Accumulator) {
defer a.wg.Done()
for d := range msgs {
metrics, err := a.parser.Parse(d.Body)
if err != nil {
log.Printf("E! %v: error parsing metric - %v", err, string(d.Body))
} else {
for _, m := range metrics {
acc.AddFields(m.Name(), m.Fields(), m.Tags(), m.Time())
}
}
d.Ack(false)
}
log.Printf("I! AMQP consumer queue closed")
}
func (a *AMQPConsumer) Stop() {
err := a.conn.Close()
if err != nil && err != amqp.ErrClosed {
log.Printf("E! Error closing AMQP connection: %s", err)
return
}
a.wg.Wait()
log.Println("I! Stopped AMQP service")
}
func init() {
inputs.Add("amqp_consumer", func() telegraf.Input {
return &AMQPConsumer{
AuthMethod: DefaultAuthMethod,
PrefetchCount: DefaultPrefetchCount,
}
})
}