add meep-watchdog package

/*

 * Copyright (c) 2019

 * InterDigital Communications, Inc.

 * All rights reserved.

 *

 * The information provided herein is the proprietary and confidential

 * information of InterDigital Communications, Inc.

 */

package watchdog

const pingPrefix string = "ping:"

const pongPrefix string = "pong:"

module github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-watchdog

go 1.12

require (

	github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-logger v0.0.0

	github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-redis v0.0.0

	github.com/KromDaniel/rejonson v0.0.0-20180822072824-00b5bcf2b351

	github.com/go-redis/redis v6.15.2+incompatible

)

replace github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-logger => ../../go-packages/meep-logger

replace github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-redis => ../../go-packages/meep-redis

github.com/KromDaniel/rejonson v0.0.0-20180822072824-00b5bcf2b351 h1:1u1XrfCBnY+GijnyU6O1k4odp5TnqZQTsp5v7+n/E4Y=

github.com/KromDaniel/rejonson v0.0.0-20180822072824-00b5bcf2b351/go.mod h1:HxwfbuElTuGf+/uKZfjJrCnv0BmmpkPJDI7gBwj1KkM=

github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=

github.com/go-redis/redis v6.15.2+incompatible h1:9SpNVG76gr6InJGxoZ6IuuxaCOQwDAhzyXg+Bs+0Sb4=

github.com/go-redis/redis v6.15.2+incompatible/go.mod h1:NAIEuMOZ/fxfXJIrKDQDz8wamY7mA7PouImQ2Jvg6kA=

github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=

github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=

github.com/sirupsen/logrus v1.4.1 h1:GL2rEmy6nsikmW0r8opw9JIRScdMF5hA8cOYLH7In1k=

github.com/sirupsen/logrus v1.4.1/go.mod h1:ni0Sbl8bgC9z8RoU9G6nDWqqs/fq4eDPysMBDgk/93Q=

github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=

github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=

golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33 h1:I6FyU15t786LL7oL/hn43zqTuEGr4PN7F4XJ1p4E3Y8=

golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=

/*

 * Copyright (c) 2019

 * InterDigital Communications, Inc.

 * All rights reserved.

 *

 * The information provided herein is the proprietary and confidential

 * information of InterDigital Communications, Inc.

 */

package watchdog

import (

	"errors"

	"strings"

	log "github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-logger"

	redis "github.com/InterDigitalInc/AdvantEDGE/go-packages/meep-redis"

)

// Pingee - Implements a Redis Pingee`

type Pingee struct {

	name        string

	isStarted   bool

	pingChannel string

	pongChannel string

	rc          *redis.Connector

}

// NewPingee - Create, Initialize and connect  a pingee

func NewPingee(dbAddr string, name string) (p *Pingee, err error) {

	if name == "" {

		err = errors.New("Missing pingee name")

		log.Error(err)

		return nil, err

	}

	p = new(Pingee)

	p.name = name

	p.isStarted = false

	p.pingChannel = p.name + ":ping"

	p.pongChannel = p.name + ":pong"

	// Connect to Redis DB

	p.rc, err = redis.NewConnector(dbAddr)

	if err != nil {

		log.Error("Pingee ", p.name, " failed connection to Redis")

		log.Error(err)

		return nil, err

	}

	log.Debug("Pingee created ", p.name)

	return p, nil

}

// Start - Listen & reply to ping requests

// - use on pingee side

func (p *Pingee) Start() (err error) {

	err = p.rc.Subscribe(p.pingChannel)

	if err != nil {

		log.Error("Pingee ", p.name, " failed to subscribe to ", p.pingChannel)

		log.Error(err)

		return err

	}

	// Listen for subscribed pings. Provide event handler method.

	go func() {

		_ = p.rc.Listen(p.pingHandler)

	}()

	p.isStarted = true

	return nil

}

// Stop - Unsubscribe and stop listening to ping channel

func (p *Pingee) Stop() (err error) {

	if p.isStarted {

		p.isStarted = false

		p.rc.StopListen()

		p.rc.Unsubscribe(p.pingChannel)

		log.Debug("Pignee stopped ", p.name)

	}

	return nil

}

func (p *Pingee) pingHandler(channel string, payload string) {

	pingMsg := strings.TrimPrefix(payload, pingPrefix)

	pongMsg := pongPrefix + pingMsg

	p.rc.Publish(p.pongChannel, pongMsg)

}