go-ethereum/swarm/network/simulation/example_test.go

140 lines
4.1 KiB
Go

// Copyright 2018 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 simulation_test
import (
"context"
"fmt"
"sync"
"time"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/node"
"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
"github.com/ethereum/go-ethereum/swarm/network"
"github.com/ethereum/go-ethereum/swarm/network/simulation"
)
// Every node can have a Kademlia associated using the node bucket under
// BucketKeyKademlia key. This allows to use WaitTillHealthy to block until
// all nodes have the their Kadmlias healthy.
func ExampleSimulation_WaitTillHealthy() {
sim := simulation.New(map[string]simulation.ServiceFunc{
"bzz": func(ctx *adapters.ServiceContext, b *sync.Map) (node.Service, func(), error) {
addr := network.NewAddr(ctx.Config.Node())
hp := network.NewHiveParams()
hp.Discovery = false
config := &network.BzzConfig{
OverlayAddr: addr.Over(),
UnderlayAddr: addr.Under(),
HiveParams: hp,
}
kad := network.NewKademlia(addr.Over(), network.NewKadParams())
// store kademlia in node's bucket under BucketKeyKademlia
// so that it can be found by WaitTillHealthy method.
b.Store(simulation.BucketKeyKademlia, kad)
return network.NewBzz(config, kad, nil, nil, nil), nil, nil
},
})
defer sim.Close()
_, err := sim.AddNodesAndConnectRing(10)
if err != nil {
// handle error properly...
panic(err)
}
ctx, cancel := context.WithTimeout(context.Background(), 60*time.Second)
defer cancel()
ill, err := sim.WaitTillHealthy(ctx, 2)
if err != nil {
// inspect the latest detected not healthy kademlias
for id, kad := range ill {
fmt.Println("Node", id)
fmt.Println(kad.String())
}
// handle error...
}
// continue with the test
}
// Watch all peer events in the simulation network, buy receiving from a channel.
func ExampleSimulation_PeerEvents() {
sim := simulation.New(nil)
defer sim.Close()
events := sim.PeerEvents(context.Background(), sim.NodeIDs())
go func() {
for e := range events {
if e.Error != nil {
log.Error("peer event", "err", e.Error)
continue
}
log.Info("peer event", "node", e.NodeID, "peer", e.PeerID, "type", e.Event.Type)
}
}()
}
// Detect when a nodes drop a peer.
func ExampleSimulation_PeerEvents_disconnections() {
sim := simulation.New(nil)
defer sim.Close()
disconnections := sim.PeerEvents(
context.Background(),
sim.NodeIDs(),
simulation.NewPeerEventsFilter().Drop(),
)
go func() {
for d := range disconnections {
if d.Error != nil {
log.Error("peer drop", "err", d.Error)
continue
}
log.Warn("peer drop", "node", d.NodeID, "peer", d.PeerID)
}
}()
}
// Watch multiple types of events or messages. In this case, they differ only
// by MsgCode, but filters can be set for different types or protocols, too.
func ExampleSimulation_PeerEvents_multipleFilters() {
sim := simulation.New(nil)
defer sim.Close()
msgs := sim.PeerEvents(
context.Background(),
sim.NodeIDs(),
// Watch when bzz messages 1 and 4 are received.
simulation.NewPeerEventsFilter().ReceivedMessages().Protocol("bzz").MsgCode(1),
simulation.NewPeerEventsFilter().ReceivedMessages().Protocol("bzz").MsgCode(4),
)
go func() {
for m := range msgs {
if m.Error != nil {
log.Error("bzz message", "err", m.Error)
continue
}
log.Info("bzz message", "node", m.NodeID, "peer", m.PeerID)
}
}()
}