consumer_metric/consumer/consumer-handler.go

package consumer

import (
	"fmt"
	"strings"
	"sync/atomic"
	"time"

	"git.loafle.net/commons/logging-go"
	oc "git.loafle.net/overflow/consumer"
	"git.loafle.net/overflow/consumer_metric/config"
	oe "git.loafle.net/overflow/external-go"
	oei "git.loafle.net/overflow/external-go/influxdb"
	"github.com/influxdata/influxdb/client/v2"
	"github.com/segmentio/kafka-go"
)

type ConsumerHandler interface {
	oc.ConsumerHandler
}

type ConsumerHandlers struct {
	oc.ConsumerHandlers

	Config *config.Config

	InfluxDBClientName string

	validated atomic.Value
}

func (ch *ConsumerHandlers) Init(consumerCtx oc.ConsumerCtx) error {
	if err := ch.ConsumerHandlers.Init(consumerCtx); nil != err {
		return err
	}
	oe.InitPackage(ch.Config.External)

	return nil
}

func (ch *ConsumerHandlers) OnStart(consumerCtx oc.ConsumerCtx) error {
	if err := ch.ConsumerHandlers.OnStart(consumerCtx); nil != err {
		return err
	}
	oe.StartPackage(ch.Config.External)

	return nil
}

func (ch *ConsumerHandlers) OnStop(consumerCtx oc.ConsumerCtx) {
	oe.StopPackage(ch.Config.External)

	ch.ConsumerHandlers.OnStop(consumerCtx)
}

func (ch *ConsumerHandlers) Destroy(consumerCtx oc.ConsumerCtx) {
	oe.DestroyPackage(ch.Config.External)

	ch.ConsumerHandlers.Destroy(consumerCtx)
}

func (ch *ConsumerHandlers) OnMessage(msg *kafka.Message) {
	c := oei.ClientFor(ch.InfluxDBClientName)
	if nil == c {
		logging.Logger().Errorf("Client of InfluxDB is not valid")
		return
	}

	bp := oei.BatchPointsFor("")
	if nil == bp {
		logging.Logger().Errorf("BatchPoints of InfluxDB is not valid")
		return
	}

	// Create a point and add to batch
	tags := map[string]string{"cpu": "cpu-total"}
	fields := map[string]interface{}{
		"idle":   10.1,
		"system": 53.3,
		"user":   46.6,
	}

	pt, err := client.NewPoint("cpu_usage", tags, fields, time.Now())
	if nil != err {
		logging.Logger().Error(err)
	}
	bp.AddPoint(pt)

	if err := c.Write(bp); err != nil {
		logging.Logger().Error(err)
	}
}

func (ch *ConsumerHandlers) Validate() error {
	if err := ch.ConsumerHandlers.Validate(); nil != err {
		return err
	}

	if nil != ch.validated.Load() {
		return nil
	}
	ch.validated.Store(true)

	if "" == strings.TrimSpace(ch.InfluxDBClientName) {
		return fmt.Errorf("InfluxDBClientName is not valid")
	}

	return nil
}