// Copyright 2015 The go-ethereum Authors

// This file is part of the go-ethereum library.

//

// The go-ethereum library is free software: you can redistribute it and/or modify

// it under the terms of the GNU Lesser General Public License as published by

// the Free Software Foundation, either version 3 of the License, or

// (at your option) any later version.

//

// The go-ethereum library is distributed in the hope that it will be useful,

// but WITHOUT ANY WARRANTY; without even the implied warranty of

// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

// GNU Lesser General Public License for more details.

//

// You should have received a copy of the GNU Lesser General Public License

// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.

package node_test

import (

"fmt"

"log"

"github.com/ethereum/go-ethereum/node"

)

// SampleLifecycle is a trivial network service that can be attached to a node for

// life cycle management.

//

// The following methods are needed to implement a node.Lifecycle:

// - Start() error - method invoked when the node is ready to start the service

// - Stop() error - method invoked when the node terminates the service

type SampleLifecycle struct{}

func (s *SampleLifecycle) Start() error { fmt.Println("Service starting..."); return nil }

func (s *SampleLifecycle) Stop() error { fmt.Println("Service stopping..."); return nil }

func ExampleLifecycle() {

// Create a network node to run protocols with the default values.

stack, err := node.New(&node.Config{})

if err != nil {

log.Fatalf("Failed to create network node: %v", err)

}

defer stack.Close()

// Create and register a simple network Lifecycle.

service := new(SampleLifecycle)

stack.RegisterLifecycle(service)

// Boot up the entire protocol stack, do a restart and terminate

if err := stack.Start(); err != nil {

log.Fatalf("Failed to start the protocol stack: %v", err)

}

if err := stack.Close(); err != nil {

log.Fatalf("Failed to stop the protocol stack: %v", err)

}

// Output:

// Service starting...

// Service stopping...

}