// 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
import (
"encoding/json"
"errors"
"io/ioutil"
"math/rand"
"os"
"time"
"github.com/ethereum/go-ethereum/log"
"github.com/ethereum/go-ethereum/p2p/discover"
"github.com/ethereum/go-ethereum/p2p/simulations"
"github.com/ethereum/go-ethereum/p2p/simulations/adapters"
)
// NodeIDs returns NodeIDs for all nodes in the network.
func (s *Simulation) NodeIDs() (ids []discover.NodeID) {
nodes := s.Net.GetNodes()
ids = make([]discover.NodeID, len(nodes))
for i, node := range nodes {
ids[i] = node.ID()
}
return ids
}
// UpNodeIDs returns NodeIDs for nodes that are up in the network.
func (s *Simulation) UpNodeIDs() (ids []discover.NodeID) {
nodes := s.Net.GetNodes()
for _, node := range nodes {
if node.Up {
ids = append(ids, node.ID())
}
}
return ids
}
// DownNodeIDs returns NodeIDs for nodes that are stopped in the network.
func (s *Simulation) DownNodeIDs() (ids []discover.NodeID) {
nodes := s.Net.GetNodes()
for _, node := range nodes {
if !node.Up {
ids = append(ids, node.ID())
}
}
return ids
}
// AddNodeOption defines the option that can be passed
// to Simulation.AddNode method.
type AddNodeOption func(*adapters.NodeConfig)
// AddNodeWithMsgEvents sets the EnableMsgEvents option
// to NodeConfig.
func AddNodeWithMsgEvents(enable bool) AddNodeOption {
return func(o *adapters.NodeConfig) {
o.EnableMsgEvents = enable
}
}
// AddNodeWithService specifies a service that should be
// started on a node. This option can be repeated as variadic
// argument toe AddNode and other add node related methods.
// If AddNodeWithService is not specified, all services will be started.
func AddNodeWithService(serviceName string) AddNodeOption {
return func(o *adapters.NodeConfig) {
o.Services = append(o.Services, serviceName)
}
}
// AddNode creates a new node with random configuration,
// applies provided options to the config and adds the node to network.
// By default all services will be started on a node. If one or more
// AddNodeWithService option are provided, only specified services will be started.
func (s *Simulation) AddNode(opts ...AddNodeOption) (id discover.NodeID, err error) {
conf := adapters.RandomNodeConfig()
for _, o := range opts {
o(conf)
}
if len(conf.Services) == 0 {
conf.Services = s.serviceNames
}
node, err := s.Net.NewNodeWithConfig(conf)
if err != nil {
return id, err
}
return node.ID(), s.Net.Start(node.ID())
}
// AddNodes creates new nodes with random configurations,
// applies provided options to the config and adds nodes to network.
func (s *Simulation) AddNodes(count int, opts ...AddNodeOption) (ids []discover.NodeID, err error) {
ids = make([]discover.NodeID, 0, count)
for i := 0; i < count; i++ {
id, err := s.AddNode(opts...)
if err != nil {
return nil, err
}
ids = append(ids, id)
}
return ids, nil
}
// AddNodesAndConnectFull is a helpper method that combines
// AddNodes and ConnectNodesFull. Only new nodes will be connected.
func (s *Simulation) AddNodesAndConnectFull(count int, opts ...AddNodeOption) (ids []discover.NodeID, err error) {
if count < 2 {
return nil, errors.New("count of nodes must be at least 2")
}
ids, err = s.AddNodes(count, opts...)
if err != nil {
return nil, err
}
err = s.ConnectNodesFull(ids)
if err != nil {
return nil, err
}
return ids, nil
}
// AddNodesAndConnectChain is a helpper method that combines
// AddNodes and ConnectNodesChain. The chain will be continued from the last
// added node, if there is one in simulation using ConnectToLastNode method.
func (s *Simulation) AddNodesAndConnectChain(count int, opts ...AddNodeOption) (ids []discover.NodeID, err error) {
if count < 2 {
return nil, errors.New("count of nodes must be at least 2")
}
id, err := s.AddNode(opts...)
if err != nil {
return nil, err
}
err = s.ConnectToLastNode(id)
if err != nil {
return nil, err
}
ids, err = s.AddNodes(count-1, opts...)
if err != nil {
return nil, err
}
ids = append([]discover.NodeID{id}, ids...)
err = s.ConnectNodesChain(ids)
if err != nil {
return nil, err
}
return ids, nil
}
// AddNodesAndConnectRing is a helpper method that combines
// AddNodes and ConnectNodesRing.
func (s *Simulation) AddNodesAndConnectRing(count int, opts ...AddNodeOption) (ids []discover.NodeID, err error) {
if count < 2 {
return nil, errors.New("count of nodes must be at least 2")
}
ids, err = s.AddNodes(count, opts...)
if err != nil {
return nil, err
}
err = s.ConnectNodesRing(ids)
if err != nil {
return nil, err
}
return ids, nil
}
// AddNodesAndConnectStar is a helpper method that combines
// AddNodes and ConnectNodesStar.
func (s *Simulation) AddNodesAndConnectStar(count int, opts ...AddNodeOption) (ids []discover.NodeID, err error) {
if count < 2 {
return nil, errors.New("count of nodes must be at least 2")
}
ids, err = s.AddNodes(count, opts...)
if err != nil {
return nil, err
}
err = s.ConnectNodesStar(ids[0], ids[1:])
if err != nil {
return nil, err
}
return ids, nil
}
//Upload a snapshot
//This method tries to open the json file provided, applies the config to all nodes
//and then loads the snapshot into the Simulation network
func (s *Simulation) UploadSnapshot(snapshotFile string, opts ...AddNodeOption) error {
f, err := os.Open(snapshotFile)
if err != nil {
return err
}
defer f.Close()
jsonbyte, err := ioutil.ReadAll(f)
if err != nil {
return err
}
var snap simulations.Snapshot
err = json.Unmarshal(jsonbyte, &snap)
if err != nil {
return err
}
//the snapshot probably has the property EnableMsgEvents not set
//just in case, set it to true!
//(we need this to wait for messages before uploading)
for _, n := range snap.Nodes {
n.Node.Config.EnableMsgEvents = true
n.Node.Config.Services = s.serviceNames
for _, o := range opts {
o(n.Node.Config)
}
}
log.Info("Waiting for p2p connections to be established...")
//now we can load the snapshot
err = s.Net.Load(&snap)
if err != nil {
return err
}
log.Info("Snapshot loaded")
return nil
}
// SetPivotNode sets the NodeID of the network's pivot node.
// Pivot node is just a specific node that should be treated
// differently then other nodes in test. SetPivotNode and
// PivotNodeID are just a convenient functions to set and
// retrieve it.
func (s *Simulation) SetPivotNode(id discover.NodeID) {
s.mu.Lock()
defer s.mu.Unlock()
s.pivotNodeID = &id
}
// PivotNodeID returns NodeID of the pivot node set by
// Simulation.SetPivotNode method.
func (s *Simulation) PivotNodeID() (id *discover.NodeID) {
s.mu.Lock()
defer s.mu.Unlock()
return s.pivotNodeID
}
// StartNode starts a node by NodeID.
func (s *Simulation) StartNode(id discover.NodeID) (err error) {
return s.Net.Start(id)
}
// StartRandomNode starts a random node.
func (s *Simulation) StartRandomNode() (id discover.NodeID, err error) {
n := s.randomDownNode()
if n == nil {
return id, ErrNodeNotFound
}
return n.ID, s.Net.Start(n.ID)
}
// StartRandomNodes starts random nodes.
func (s *Simulation) StartRandomNodes(count int) (ids []discover.NodeID, err error) {
ids = make([]discover.NodeID, 0, count)
downIDs := s.DownNodeIDs()
for i := 0; i < count; i++ {
n := s.randomNode(downIDs, ids...)
if n == nil {
return nil, ErrNodeNotFound
}
err = s.Net.Start(n.ID)
if err != nil {
return nil, err
}
ids = append(ids, n.ID)
}
return ids, nil
}
// StopNode stops a node by NodeID.
func (s *Simulation) StopNode(id discover.NodeID) (err error) {
return s.Net.Stop(id)
}
// StopRandomNode stops a random node.
func (s *Simulation) StopRandomNode() (id discover.NodeID, err error) {
n := s.randomUpNode()
if n == nil {
return id, ErrNodeNotFound
}
return n.ID, s.Net.Stop(n.ID)
}
// StopRandomNodes stops random nodes.
func (s *Simulation) StopRandomNodes(count int) (ids []discover.NodeID, err error) {
ids = make([]discover.NodeID, 0, count)
upIDs := s.UpNodeIDs()
for i := 0; i < count; i++ {
n := s.randomNode(upIDs, ids...)
if n == nil {
return nil, ErrNodeNotFound
}
err = s.Net.Stop(n.ID)
if err != nil {
return nil, err
}
ids = append(ids, n.ID)
}
return ids, nil
}
// seed the random generator for Simulation.randomNode.
func init() {
rand.Seed(time.Now().UnixNano())
}
// randomUpNode returns a random SimNode that is up.
// Arguments are NodeIDs for nodes that should not be returned.
func (s *Simulation) randomUpNode(exclude ...discover.NodeID) *adapters.SimNode {
return s.randomNode(s.UpNodeIDs(), exclude...)
}
// randomUpNode returns a random SimNode that is not up.
func (s *Simulation) randomDownNode(exclude ...discover.NodeID) *adapters.SimNode {
return s.randomNode(s.DownNodeIDs(), exclude...)
}
// randomUpNode returns a random SimNode from the slice of NodeIDs.
func (s *Simulation) randomNode(ids []discover.NodeID, exclude ...discover.NodeID) *adapters.SimNode {
for _, e := range exclude {
var i int
for _, id := range ids {
if id == e {
ids = append(ids[:i], ids[i+1:]...)
} else {
i++
}
}
}
l := len(ids)
if l == 0 {
return nil
}
n := s.Net.GetNode(ids[rand.Intn(l)])
node, _ := n.Node.(*adapters.SimNode)
return node
}