node: customizable protocol and service stacks

This commit is contained in:
Péter Szilágyi 2015-11-05 23:57:57 +02:00
parent 168d0e9e45
commit 9e1d9bff3b
13 changed files with 1333 additions and 13 deletions

171
node/config.go Normal file
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// 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
import (
"crypto/ecdsa"
"encoding/json"
"io/ioutil"
"net"
"os"
"path/filepath"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/logger"
"github.com/ethereum/go-ethereum/logger/glog"
"github.com/ethereum/go-ethereum/p2p/discover"
"github.com/ethereum/go-ethereum/p2p/nat"
)
var (
datadirPrivateKey = "nodekey" // Path within the datadir to the node's private key
datadirStaticNodes = "static-nodes.json" // Path within the datadir to the static node list
datadirTrustedNodes = "trusted-nodes.json" // Path within the datadir to the trusted node list
datadirNodeDatabase = "nodes" // Path within the datadir to store the node infos
)
// Config represents a small collection of configuration values to fine tune the
// P2P network layer of a protocol stack. These values can be further extended by
// all registered services.
type Config struct {
// DataDir is the file system folder the node should use for any data storage
// requirements. The configured data directory will not be directly shared with
// registered services, instead those can use utility methods to create/access
// databases or flat files. This enables ephemeral nodes which can fully reside
// in memory.
DataDir string
// This field should be a valid secp256k1 private key that will be used for both
// remote peer identification as well as network traffic encryption. If no key
// is configured, the preset one is loaded from the data dir, generating it if
// needed.
PrivateKey *ecdsa.PrivateKey
// Name sets the node name of this server. Use common.MakeName to create a name
// that follows existing conventions.
Name string
// NoDiscovery specifies whether the peer discovery mechanism should be started
// or not. Disabling is usually useful for protocol debugging (manual topology).
NoDiscovery bool
// Bootstrap nodes used to establish connectivity with the rest of the network.
BootstrapNodes []*discover.Node
// Network interface address on which the node should listen for inbound peers.
ListenAddr string
// If set to a non-nil value, the given NAT port mapper is used to make the
// listening port available to the Internet.
NAT nat.Interface
// If Dialer is set to a non-nil value, the given Dialer is used to dial outbound
// peer connections.
Dialer *net.Dialer
// If NoDial is true, the node will not dial any peers.
NoDial bool
// MaxPeers is the maximum number of peers that can be connected. If this is
// set to zero, then only the configured static and trusted peers can connect.
MaxPeers int
// MaxPendingPeers is the maximum number of peers that can be pending in the
// handshake phase, counted separately for inbound and outbound connections.
// Zero defaults to preset values.
MaxPendingPeers int
}
// NodeKey retrieves the currently configured private key of the node, checking
// first any manually set key, falling back to the one found in the configured
// data folder. If no key can be found, a new one is generated.
func (c *Config) NodeKey() *ecdsa.PrivateKey {
// Use any specifically configured key
if c.PrivateKey != nil {
return c.PrivateKey
}
// Generate ephemeral key if no datadir is being used
if c.DataDir == "" {
key, err := crypto.GenerateKey()
if err != nil {
glog.Fatalf("Failed to generate ephemeral node key: %v", err)
}
return key
}
// Fall back to persistent key from the data directory
keyfile := filepath.Join(c.DataDir, datadirPrivateKey)
if key, err := crypto.LoadECDSA(keyfile); err == nil {
return key
}
// No persistent key found, generate and store a new one
key, err := crypto.GenerateKey()
if err != nil {
glog.Fatalf("Failed to generate node key: %v", err)
}
if err := crypto.SaveECDSA(keyfile, key); err != nil {
glog.V(logger.Error).Infof("Failed to persist node key: %v", err)
}
return key
}
// StaticNodes returns a list of node enode URLs configured as static nodes.
func (c *Config) StaticNodes() []*discover.Node {
return c.parsePersistentNodes(datadirStaticNodes)
}
// TrusterNodes returns a list of node enode URLs configured as trusted nodes.
func (c *Config) TrusterNodes() []*discover.Node {
return c.parsePersistentNodes(datadirTrustedNodes)
}
// parsePersistentNodes parses a list of discovery node URLs loaded from a .json
// file from within the data directory.
func (c *Config) parsePersistentNodes(file string) []*discover.Node {
// Short circuit if no node config is present
if c.DataDir == "" {
return nil
}
path := filepath.Join(c.DataDir, file)
if _, err := os.Stat(path); err != nil {
return nil
}
// Load the nodes from the config file
blob, err := ioutil.ReadFile(path)
if err != nil {
glog.V(logger.Error).Infof("Failed to access nodes: %v", err)
return nil
}
nodelist := []string{}
if err := json.Unmarshal(blob, &nodelist); err != nil {
glog.V(logger.Error).Infof("Failed to load nodes: %v", err)
return nil
}
// Interpret the list as a discovery node array
var nodes []*discover.Node
for _, url := range nodelist {
if url == "" {
continue
}
node, err := discover.ParseNode(url)
if err != nil {
glog.V(logger.Error).Infof("Node URL %s: %v\n", url, err)
continue
}
nodes = append(nodes, node)
}
return nodes
}

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// 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
import (
"bytes"
"io/ioutil"
"os"
"path/filepath"
"testing"
"github.com/ethereum/go-ethereum/crypto"
)
// Tests that datadirs can be successfully created, be them manually configured
// ones or automatically generated temporary ones.
func TestDatadirCreation(t *testing.T) {
// Create a temporary data dir and check that it can be used by a node
dir, err := ioutil.TempDir("", "")
if err != nil {
t.Fatalf("failed to create manual data dir: %v", err)
}
defer os.RemoveAll(dir)
if _, err := New(&Config{DataDir: dir}); err != nil {
t.Fatalf("failed to create stack with existing datadir: %v", err)
}
// Generate a long non-existing datadir path and check that it gets created by a node
dir = filepath.Join(dir, "a", "b", "c", "d", "e", "f")
if _, err := New(&Config{DataDir: dir}); err != nil {
t.Fatalf("failed to create stack with creatable datadir: %v", err)
}
if _, err := os.Stat(dir); err != nil {
t.Fatalf("freshly created datadir not accessible: %v", err)
}
// Verify that an impossible datadir fails creation
file, err := ioutil.TempFile("", "")
if err != nil {
t.Fatalf("failed to create temporary file: %v", err)
}
defer os.Remove(file.Name())
dir = filepath.Join(file.Name(), "invalid/path")
if _, err := New(&Config{DataDir: dir}); err == nil {
t.Fatalf("protocol stack created with an invalid datadir")
}
}
// Tests that node keys can be correctly created, persisted, loaded and/or made
// ephemeral.
func TestNodeKeyPersistency(t *testing.T) {
// Create a temporary folder and make sure no key is present
dir, err := ioutil.TempDir("", "")
if err != nil {
t.Fatalf("failed to create temporary data directory: %v", err)
}
defer os.RemoveAll(dir)
if _, err := os.Stat(filepath.Join(dir, datadirPrivateKey)); err == nil {
t.Fatalf("non-created node key already exists")
}
// Configure a node with a preset key and ensure it's not persisted
key, err := crypto.GenerateKey()
if err != nil {
t.Fatalf("failed to generate one-shot node key: %v", err)
}
if _, err := New(&Config{DataDir: dir, PrivateKey: key}); err != nil {
t.Fatalf("failed to create empty stack: %v", err)
}
if _, err := os.Stat(filepath.Join(dir, datadirPrivateKey)); err == nil {
t.Fatalf("one-shot node key persisted to data directory")
}
// Configure a node with no preset key and ensure it is persisted this time
if _, err := New(&Config{DataDir: dir}); err != nil {
t.Fatalf("failed to create newly keyed stack: %v", err)
}
if _, err := os.Stat(filepath.Join(dir, datadirPrivateKey)); err != nil {
t.Fatalf("node key not persisted to data directory: %v", err)
}
key, err = crypto.LoadECDSA(filepath.Join(dir, datadirPrivateKey))
if err != nil {
t.Fatalf("failed to load freshly persisted node key: %v", err)
}
blob1, err := ioutil.ReadFile(filepath.Join(dir, datadirPrivateKey))
if err != nil {
t.Fatalf("failed to read freshly persisted node key: %v", err)
}
// Configure a new node and ensure the previously persisted key is loaded
if _, err := New(&Config{DataDir: dir}); err != nil {
t.Fatalf("failed to create previously keyed stack: %v", err)
}
blob2, err := ioutil.ReadFile(filepath.Join(dir, datadirPrivateKey))
if err != nil {
t.Fatalf("failed to read previously persisted node key: %v", err)
}
if bytes.Compare(blob1, blob2) != 0 {
t.Fatalf("persisted node key mismatch: have %x, want %x", blob2, blob1)
}
// Configure ephemeral node and ensure no key is dumped locally
if _, err := New(&Config{DataDir: ""}); err != nil {
t.Fatalf("failed to create ephemeral stack: %v", err)
}
if _, err := os.Stat(filepath.Join(".", datadirPrivateKey)); err == nil {
t.Fatalf("ephemeral node key persisted to disk")
}
}

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// 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
import "fmt"
// StopError is returned if a node fails to stop either any of its registered
// services or itself.
type StopError struct {
Server error
Services map[string]error
}
// Error generates a textual representation of the stop error.
func (e *StopError) Error() string {
return fmt.Sprintf("server: %v, services: %v", e.Server, e.Services)
}

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// 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 represents the Ethereum protocol stack container.
package node
import (
"errors"
"os"
"path/filepath"
"sync"
"syscall"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/p2p"
)
var (
ErrDatadirUsed = errors.New("datadir already used")
ErrNodeStopped = errors.New("node not started")
ErrNodeRunning = errors.New("node already running")
ErrServiceUnknown = errors.New("service not registered")
ErrServiceRegistered = errors.New("service already registered")
datadirInUseErrnos = map[uint]bool{11: true, 32: true, 35: true}
)
// Node represents a P2P node into which arbitrary services might be registered.
type Node struct {
datadir string // Path to the currently used data directory
config *p2p.Server // Configuration of the underlying P2P networking layer
stack map[string]ServiceConstructor // Protocol stack registered into this node
emux *event.TypeMux // Event multiplexer used between the services of a stack
running *p2p.Server // Currently running P2P networking layer
services map[string]Service // Currently running services
lock sync.RWMutex
}
// New creates a new P2P node, ready for protocol registration.
func New(conf *Config) (*Node, error) {
// Ensure the data directory exists, failing if it cannot be created
if conf.DataDir != "" {
if err := os.MkdirAll(conf.DataDir, 0700); err != nil {
return nil, err
}
}
// Assemble the networking layer and the node itself
nodeDbPath := ""
if conf.DataDir != "" {
nodeDbPath = filepath.Join(conf.DataDir, datadirNodeDatabase)
}
return &Node{
datadir: conf.DataDir,
config: &p2p.Server{
PrivateKey: conf.NodeKey(),
Name: conf.Name,
Discovery: !conf.NoDiscovery,
BootstrapNodes: conf.BootstrapNodes,
StaticNodes: conf.StaticNodes(),
TrustedNodes: conf.TrusterNodes(),
NodeDatabase: nodeDbPath,
ListenAddr: conf.ListenAddr,
NAT: conf.NAT,
Dialer: conf.Dialer,
NoDial: conf.NoDial,
MaxPeers: conf.MaxPeers,
MaxPendingPeers: conf.MaxPendingPeers,
},
stack: make(map[string]ServiceConstructor),
emux: new(event.TypeMux),
}, nil
}
// Register injects a new service into the node's stack.
func (n *Node) Register(id string, constructor ServiceConstructor) error {
n.lock.Lock()
defer n.lock.Unlock()
// Short circuit if the node is running or if the id is taken
if n.running != nil {
return ErrNodeRunning
}
if _, ok := n.stack[id]; ok {
return ErrServiceRegistered
}
// Otherwise register the service and return
n.stack[id] = constructor
return nil
}
// Unregister removes a service from a node's stack. If the node is currently
// running, an error will be returned.
func (n *Node) Unregister(id string) error {
n.lock.Lock()
defer n.lock.Unlock()
// Short circuit if the node is running, or if the service is unknown
if n.running != nil {
return ErrNodeRunning
}
if _, ok := n.stack[id]; !ok {
return ErrServiceUnknown
}
// Otherwise drop the service and return
delete(n.stack, id)
return nil
}
// Start create a live P2P node and starts running it.
func (n *Node) Start() error {
n.lock.Lock()
defer n.lock.Unlock()
// Short circuit if the node's already running
if n.running != nil {
return ErrNodeRunning
}
// Otherwise copy and specialize the P2P configuration
running := new(p2p.Server)
*running = *n.config
ctx := &ServiceContext{
dataDir: n.datadir,
EventMux: n.emux,
}
services := make(map[string]Service)
for id, constructor := range n.stack {
service, err := constructor(ctx)
if err != nil {
return err
}
services[id] = service
}
// Gather the protocols and start the freshly assembled P2P server
for _, service := range services {
running.Protocols = append(running.Protocols, service.Protocols()...)
}
if err := running.Start(); err != nil {
if errno, ok := err.(syscall.Errno); ok && datadirInUseErrnos[uint(errno)] {
return ErrDatadirUsed
}
return err
}
// Start each of the services
started := []string{}
for id, service := range services {
// Start the next service, stopping all previous upon failure
if err := service.Start(); err != nil {
for _, id := range started {
services[id].Stop()
}
return err
}
// Mark the service started for potential cleanup
started = append(started, id)
}
// Finish initializing the startup
n.services = services
n.running = running
return nil
}
// Stop terminates a running node along with all it's services. In the node was
// not started, an error is returned.
func (n *Node) Stop() error {
n.lock.Lock()
defer n.lock.Unlock()
// Short circuit if the node's not running
if n.running == nil {
return ErrNodeStopped
}
// Otherwise terminate all the services and the P2P server too
failure := &StopError{
Services: make(map[string]error),
}
for id, service := range n.services {
if err := service.Stop(); err != nil {
failure.Services[id] = err
}
}
n.running.Stop()
n.services = nil
n.running = nil
if len(failure.Services) > 0 {
return failure
}
return nil
}
// Restart terminates a running node and boots up a new one in its place. If the
// node isn't running, an error is returned.
func (n *Node) Restart() error {
if err := n.Stop(); err != nil {
return err
}
if err := n.Start(); err != nil {
return err
}
return nil
}
// Server retrieves the currently running P2P network layer. This method is meant
// only to inspect fields of the currently running server, life cycle management
// should be left to this Node entity.
func (n *Node) Server() *p2p.Server {
n.lock.RLock()
defer n.lock.RUnlock()
return n.running
}
// Service retrieves a currently running services registered under a given id.
func (n *Node) Service(id string) Service {
n.lock.RLock()
defer n.lock.RUnlock()
if n.services == nil {
return nil
}
return n.services[id]
}
// DataDir retrieves the current datadir used by the protocol stack.
func (n *Node) DataDir() string {
return n.datadir
}
// EventMux retrieves the event multiplexer used by all the network services in
// the current protocol stack.
func (n *Node) EventMux() *event.TypeMux {
return n.emux
}

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// 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"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/p2p/discover"
)
// SampleService 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.Service:
// - Protocols() []p2p.Protocol - devp2p protocols the service can communicate on
// - Start() error - method invoked when the node is ready to start the service
// - Stop() error - method invoked when the node terminates the service
type SampleService struct{}
func (s *SampleService) Protocols() []p2p.Protocol { return nil }
func (s *SampleService) Start() error { fmt.Println("Sample service starting..."); return nil }
func (s *SampleService) Stop() error { fmt.Println("Sample service stopping..."); return nil }
func ExampleUsage() {
// Create a network node to run protocols with the default values. The below list
// is only used to display each of the configuration options. All of these could
// have been ommited if the default behavior is desired.
nodeConfig := &node.Config{
DataDir: "", // Empty uses ephemeral storage
PrivateKey: nil, // Nil generates a node key on the fly
Name: "", // Any textual node name is allowed
NoDiscovery: false, // Can disable discovering remote nodes
BootstrapNodes: []*discover.Node{}, // List of bootstrap nodes to use
ListenAddr: ":0", // Network interface to listen on
NAT: nil, // UPnP port mapper to use for crossing firewalls
Dialer: nil, // Custom dialer to use for establishing peer connections
NoDial: false, // Can prevent this node from dialing out
MaxPeers: 0, // Number of peers to allow
MaxPendingPeers: 0, // Number of peers allowed to handshake concurrently
}
stack, err := node.New(nodeConfig)
if err != nil {
log.Fatalf("Failed to create network node: %v", err)
}
// Create and register a simple network service. This is done through the definition
// of a node.ServiceConstructor that will instantiate a node.Service. The reason for
// the factory method approach is to support service restarts without relying on the
// individual implementations' support for such operations.
constructor := func(context *node.ServiceContext) (node.Service, error) {
return new(SampleService), nil
}
if err := stack.Register("my sample service", constructor); err != nil {
log.Fatalf("Failed to register service: %v", err)
}
// 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.Restart(); err != nil {
log.Fatalf("Failed to restart the protocol stack: %v", err)
}
if err := stack.Stop(); err != nil {
log.Fatalf("Failed to stop the protocol stack: %v", err)
}
// Output:
// Sample service starting...
// Sample service stopping...
// Sample service starting...
// Sample service stopping...
}

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// 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
import (
"errors"
"io/ioutil"
"os"
"testing"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/p2p"
)
var (
testNodeKey, _ = crypto.GenerateKey()
testNodeConfig = &Config{
PrivateKey: testNodeKey,
Name: "test node",
}
)
// Tests that an empty protocol stack can be started, restarted and stopped.
func TestNodeLifeCycle(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Ensure that a stopped node can be stopped again
for i := 0; i < 3; i++ {
if err := stack.Stop(); err != ErrNodeStopped {
t.Fatalf("iter %d: stop failure mismatch: have %v, want %v", i, err, ErrNodeStopped)
}
}
// Ensure that a node can be successfully started, but only once
if err := stack.Start(); err != nil {
t.Fatalf("failed to start node: %v", err)
}
if err := stack.Start(); err != ErrNodeRunning {
t.Fatalf("start failure mismatch: have %v, want %v ", err, ErrNodeRunning)
}
// Ensure that a node can be restarted arbitrarily many times
for i := 0; i < 3; i++ {
if err := stack.Restart(); err != nil {
t.Fatalf("iter %d: failed to restart node: %v", i, err)
}
}
// Ensure that a node can be stopped, but only once
if err := stack.Stop(); err != nil {
t.Fatalf("failed to stop node: %v", err)
}
if err := stack.Stop(); err != ErrNodeStopped {
t.Fatalf("stop failure mismatch: have %v, want %v ", err, ErrNodeStopped)
}
}
// Tests that if the data dir is already in use, an appropriate error is returned.
func TestNodeUsedDataDir(t *testing.T) {
// Create a temporary folder to use as the data directory
dir, err := ioutil.TempDir("", "")
if err != nil {
t.Fatalf("failed to create temporary data directory: %v", err)
}
defer os.RemoveAll(dir)
// Create a new node based on the data directory
original, err := New(&Config{DataDir: dir})
if err != nil {
t.Fatalf("failed to create original protocol stack: %v", err)
}
if err := original.Start(); err != nil {
t.Fatalf("failed to start original protocol stack: %v", err)
}
defer original.Stop()
// Create a second node based on the same data directory and ensure failure
duplicate, err := New(&Config{DataDir: dir})
if err != nil {
t.Fatalf("failed to create duplicate protocol stack: %v", err)
}
if err := duplicate.Start(); err != ErrDatadirUsed {
t.Fatalf("duplicate datadir failure mismatch: have %v, want %v", err, ErrDatadirUsed)
}
}
// NoopService is a trivial implementation of the Service interface.
type NoopService struct{}
func (s *NoopService) Protocols() []p2p.Protocol { return nil }
func (s *NoopService) Start() error { return nil }
func (s *NoopService) Stop() error { return nil }
func NewNoopService(*ServiceContext) (Service, error) { return new(NoopService), nil }
// Tests whether services can be registered and unregistered.
func TestServiceRegistry(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Create a batch of dummy services and ensure they don't exist
ids := []string{"A", "B", "C"}
for i, id := range ids {
if err := stack.Unregister(id); err != ErrServiceUnknown {
t.Fatalf("service %d: pre-unregistration failure mismatch: have %v, want %v", i, err, ErrServiceUnknown)
}
}
// Register the services, checking that the operation succeeds only once
for i, id := range ids {
if err := stack.Register(id, NewNoopService); err != nil {
t.Fatalf("service %d: registration failed: %v", i, err)
}
if err := stack.Register(id, NewNoopService); err != ErrServiceRegistered {
t.Fatalf("service %d: registration failure mismatch: have %v, want %v", i, err, ErrServiceRegistered)
}
}
// Unregister the services, checking that the operation succeeds only once
for i, id := range ids {
if err := stack.Unregister(id); err != nil {
t.Fatalf("service %d: unregistration failed: %v", i, err)
}
if err := stack.Unregister(id); err != ErrServiceUnknown {
t.Fatalf("service %d: unregistration failure mismatch: have %v, want %v", i, err, ErrServiceUnknown)
}
}
}
// InstrumentedService is an implementation of Service for which all interface
// methods can be instrumented both return value as well as event hook wise.
type InstrumentedService struct {
protocols []p2p.Protocol
start error
stop error
protocolsHook func()
startHook func()
stopHook func()
}
func (s *InstrumentedService) Protocols() []p2p.Protocol {
if s.protocolsHook != nil {
s.protocolsHook()
}
return s.protocols
}
func (s *InstrumentedService) Start() error {
if s.startHook != nil {
s.startHook()
}
return s.start
}
func (s *InstrumentedService) Stop() error {
if s.stopHook != nil {
s.stopHook()
}
return s.stop
}
// Tests that registered services get started and stopped correctly.
func TestServiceLifeCycle(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Register a batch of life-cycle instrumented services
ids := []string{"A", "B", "C"}
started := make(map[string]bool)
stopped := make(map[string]bool)
for i, id := range ids {
id := id // Closure for the constructor
constructor := func(*ServiceContext) (Service, error) {
return &InstrumentedService{
startHook: func() { started[id] = true },
stopHook: func() { stopped[id] = true },
}, nil
}
if err := stack.Register(id, constructor); err != nil {
t.Fatalf("service %d: registration failed: %v", i, err)
}
}
// Start the node and check that all services are running
if err := stack.Start(); err != nil {
t.Fatalf("failed to start protocol stack: %v", err)
}
for i, id := range ids {
if !started[id] {
t.Fatalf("service %d: freshly started service not running", i)
}
if stopped[id] {
t.Fatalf("service %d: freshly started service already stopped", i)
}
if stack.Service(id) == nil {
t.Fatalf("service %d: freshly started service unaccessible", i)
}
}
// Stop the node and check that all services have been stopped
if err := stack.Stop(); err != nil {
t.Fatalf("failed to stop protocol stack: %v", err)
}
for i, id := range ids {
if !stopped[id] {
t.Fatalf("service %d: freshly terminated service still running", i)
}
if service := stack.Service(id); service != nil {
t.Fatalf("service %d: freshly terminated service still accessible: %v", i, service)
}
}
}
// Tests that services are restarted cleanly as new instances.
func TestServiceRestarts(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Define a service that does not support restarts
var (
running bool
started int
)
constructor := func(*ServiceContext) (Service, error) {
running = false
return &InstrumentedService{
startHook: func() {
if running {
panic("already running")
}
running = true
started++
},
}, nil
}
// Register the service and start the protocol stack
if err := stack.Register("service", constructor); err != nil {
t.Fatalf("failed to register the service: %v", err)
}
if err := stack.Start(); err != nil {
t.Fatalf("failed to start protocol stack: %v", err)
}
defer stack.Stop()
if running != true || started != 1 {
t.Fatalf("running/started mismatch: have %v/%d, want true/1", running, started)
}
// Restart the stack a few times and check successful service restarts
for i := 0; i < 3; i++ {
if err := stack.Restart(); err != nil {
t.Fatalf("iter %d: failed to restart stack: %v", i, err)
}
}
if running != true || started != 4 {
t.Fatalf("running/started mismatch: have %v/%d, want true/4", running, started)
}
}
// Tests that if a service fails to initialize itself, none of the other services
// will be allowed to even start.
func TestServiceConstructionAbortion(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Define a batch of good services
ids := []string{"A", "B", "C", "D", "E", "F"}
started := make(map[string]bool)
for i, id := range ids {
id := id // Closure for the constructor
constructor := func(*ServiceContext) (Service, error) {
return &InstrumentedService{
startHook: func() { started[id] = true },
}, nil
}
if err := stack.Register(id, constructor); err != nil {
t.Fatalf("service %d: registration failed: %v", i, err)
}
}
// Register a service that fails to construct itself
failure := errors.New("fail")
failer := func(*ServiceContext) (Service, error) {
return nil, failure
}
if err := stack.Register("failer", failer); err != nil {
t.Fatalf("failer registration failed: %v", err)
}
// Start the protocol stack and ensure none of the services get started
for i := 0; i < 100; i++ {
if err := stack.Start(); err != failure {
t.Fatalf("iter %d: stack startup failure mismatch: have %v, want %v", i, err, failure)
}
for i, id := range ids {
if started[id] {
t.Fatalf("service %d: started should not have", i)
}
delete(started, id)
}
}
}
// Tests that if a service fails to start, all others started before it will be
// shut down.
func TestServiceStartupAbortion(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Register a batch of good services
ids := []string{"A", "B", "C", "D", "E", "F"}
started := make(map[string]bool)
stopped := make(map[string]bool)
for i, id := range ids {
id := id // Closure for the constructor
constructor := func(*ServiceContext) (Service, error) {
return &InstrumentedService{
startHook: func() { started[id] = true },
stopHook: func() { stopped[id] = true },
}, nil
}
if err := stack.Register(id, constructor); err != nil {
t.Fatalf("service %d: registration failed: %v", i, err)
}
}
// Register a service that fails to start
failure := errors.New("fail")
failer := func(*ServiceContext) (Service, error) {
return &InstrumentedService{
start: failure,
}, nil
}
if err := stack.Register("failer", failer); err != nil {
t.Fatalf("failer registration failed: %v", err)
}
// Start the protocol stack and ensure all started services stop
for i := 0; i < 100; i++ {
if err := stack.Start(); err != failure {
t.Fatalf("iter %d: stack startup failure mismatch: have %v, want %v", i, err, failure)
}
for i, id := range ids {
if started[id] && !stopped[id] {
t.Fatalf("service %d: started but not stopped", i)
}
delete(started, id)
delete(stopped, id)
}
}
}
// Tests that even if a registered service fails to shut down cleanly, it does
// not influece the rest of the shutdown invocations.
func TestServiceTerminationGuarantee(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Register a batch of good services
ids := []string{"A", "B", "C", "D", "E", "F"}
started := make(map[string]bool)
stopped := make(map[string]bool)
for i, id := range ids {
id := id // Closure for the constructor
constructor := func(*ServiceContext) (Service, error) {
return &InstrumentedService{
startHook: func() { started[id] = true },
stopHook: func() { stopped[id] = true },
}, nil
}
if err := stack.Register(id, constructor); err != nil {
t.Fatalf("service %d: registration failed: %v", i, err)
}
}
// Register a service that fails to shot down cleanly
failure := errors.New("fail")
failer := func(*ServiceContext) (Service, error) {
return &InstrumentedService{
stop: failure,
}, nil
}
if err := stack.Register("failer", failer); err != nil {
t.Fatalf("failer registration failed: %v", err)
}
// Start the protocol stack, and ensure that a failing shut down terminates all
for i := 0; i < 100; i++ {
// Start the stack and make sure all is online
if err := stack.Start(); err != nil {
t.Fatalf("iter %d: failed to start protocol stack: %v", i, err)
}
for j, id := range ids {
if !started[id] {
t.Fatalf("iter %d, service %d: service not running", i, j)
}
if stopped[id] {
t.Fatalf("iter %d, service %d: service already stopped", i, j)
}
}
// Stop the stack, verify failure and check all terminations
err := stack.Stop()
if err, ok := err.(*StopError); !ok {
t.Fatalf("iter %d: termination failure mismatch: have %v, want StopError", i, err)
} else {
if err.Services["failer"] != failure {
t.Fatalf("iter %d: failer termination failure mismatch: have %v, want %v", i, err.Services["failer"], failure)
}
if len(err.Services) != 1 {
t.Fatalf("iter %d: failure count mismatch: have %d, want %d", i, len(err.Services), 1)
}
}
for j, id := range ids {
if !stopped[id] {
t.Fatalf("iter %d, service %d: service not terminated", i, j)
}
delete(started, id)
delete(stopped, id)
}
}
}
// Tests that all protocols defined by individual services get launched.
func TestProtocolGather(t *testing.T) {
stack, err := New(testNodeConfig)
if err != nil {
t.Fatalf("failed to create protocol stack: %v", err)
}
// Register a batch of services with some configured number of protocols
services := map[string]int{
"Zero Protocols": 0,
"Single Protocol": 1,
"Many Protocols": 25,
}
for id, count := range services {
protocols := make([]p2p.Protocol, count)
for i := 0; i < len(protocols); i++ {
protocols[i].Name = id
protocols[i].Version = uint(i)
}
constructor := func(*ServiceContext) (Service, error) {
return &InstrumentedService{
protocols: protocols,
}, nil
}
if err := stack.Register(id, constructor); err != nil {
t.Fatalf("service %s: registration failed: %v", id, err)
}
}
// Start the services and ensure all protocols start successfully
if err := stack.Start(); err != nil {
t.Fatalf("failed to start protocol stack: %v", err)
}
defer stack.Stop()
protocols := stack.Server().Protocols
if len(protocols) != 26 {
t.Fatalf("mismatching number of protocols launched: have %d, want %d", len(protocols), 26)
}
for id, count := range services {
for ver := 0; ver < count; ver++ {
launched := false
for i := 0; i < len(protocols); i++ {
if protocols[i].Name == id && protocols[i].Version == uint(ver) {
launched = true
break
}
}
if !launched {
t.Errorf("configured protocol not launched: %s v%d", id, ver)
}
}
}
}

67
node/service.go Normal file
View File

@ -0,0 +1,67 @@
// 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
import (
"path/filepath"
"github.com/ethereum/go-ethereum/ethdb"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/p2p"
)
// ServiceContext is a collection of service independent options inherited from
// the protocol stack, that is passed to all constructors to be optionally used;
// as well as utility methods to operate on the service environment.
type ServiceContext struct {
dataDir string // Data directory for protocol persistence
EventMux *event.TypeMux // Event multiplexer used for decoupled notifications
}
// Database opens an existing database with the given name (or creates one if no
// previous can be found) from within the node's data directory. If the node is
// an ephemeral one, a memory database is returned.
func (ctx *ServiceContext) Database(name string, cache int) (ethdb.Database, error) {
if ctx.dataDir == "" {
return ethdb.NewMemDatabase()
}
return ethdb.NewLDBDatabase(filepath.Join(ctx.dataDir, name), cache)
}
// ServiceConstructor is the function signature of the constructors needed to be
// registered for service instantiation.
type ServiceConstructor func(ctx *ServiceContext) (Service, error)
// Service is an individual protocol that can be registered into a node.
//
// Notes:
// - Service life-cycle management is delegated to the node. The service is
// allowed to initialize itself upon creation, but no goroutines should be
// spun up outside of the Start method.
// - Restart logic is not required as the node will create a fresh instance
// every time a service is started.
type Service interface {
// Protocol retrieves the P2P protocols the service wishes to start.
Protocols() []p2p.Protocol
// Start spawns any goroutines required by the service.
Start() error
// Stop terminates all goroutines belonging to the service, blocking until they
// are all terminated.
Stop() error
}

60
node/service_test.go Normal file
View File

@ -0,0 +1,60 @@
// 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
import (
"io/ioutil"
"os"
"path/filepath"
"testing"
)
// Tests that service context methods work properly.
func TestServiceContext(t *testing.T) {
// Create a temporary folder and ensure no database is contained within
dir, err := ioutil.TempDir("", "")
if err != nil {
t.Fatalf("failed to create temporary data directory: %v", err)
}
defer os.RemoveAll(dir)
if _, err := os.Stat(filepath.Join(dir, "database")); err == nil {
t.Fatalf("non-created database already exists")
}
// Request the opening/creation of a database and ensure it persists to disk
ctx := &ServiceContext{dataDir: dir}
db, err := ctx.Database("persistent", 0)
if err != nil {
t.Fatalf("failed to open persistent database: %v", err)
}
db.Close()
if _, err := os.Stat(filepath.Join(dir, "persistent")); err != nil {
t.Fatalf("persistent database doesn't exists: %v", err)
}
// Request th opening/creation of an ephemeral database and ensure it's not persisted
ctx = &ServiceContext{dataDir: ""}
db, err = ctx.Database("ephemeral", 0)
if err != nil {
t.Fatalf("failed to open ephemeral database: %v", err)
}
db.Close()
if _, err := os.Stat(filepath.Join(dir, "ephemeral")); err == nil {
t.Fatalf("ephemeral database exists")
}
}

33
node/utils.go Normal file
View File

@ -0,0 +1,33 @@
// 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
import (
"path/filepath"
"github.com/ethereum/go-ethereum/ethdb"
)
// openDatabase opens an existing database with the given name from within the
// specified data directory, creating one if none exists. If the data directory
// is empty, an ephemeral memory database is returned.
func openDatabase(dataDir string, name string, cache int) (ethdb.Database, error) {
if dataDir == "" {
return ethdb.NewMemDatabase()
}
return ethdb.NewLDBDatabase(filepath.Join(dataDir, name), cache)
}

View File

@ -90,12 +90,11 @@ type transport interface {
// that was most recently active is the first element in entries.
type bucket struct{ entries []*Node }
func newTable(t transport, ourID NodeID, ourAddr *net.UDPAddr, nodeDBPath string) *Table {
func newTable(t transport, ourID NodeID, ourAddr *net.UDPAddr, nodeDBPath string) (*Table, error) {
// If no node database was given, use an in-memory one
db, err := newNodeDB(nodeDBPath, Version, ourID)
if err != nil {
glog.V(logger.Warn).Infoln("Failed to open node database:", err)
db, _ = newNodeDB("", Version, ourID)
return nil, err
}
tab := &Table{
net: t,
@ -114,7 +113,7 @@ func newTable(t transport, ourID NodeID, ourAddr *net.UDPAddr, nodeDBPath string
tab.buckets[i] = new(bucket)
}
go tab.refreshLoop()
return tab
return tab, nil
}
// Self returns the local node.

View File

@ -34,7 +34,7 @@ import (
func TestTable_pingReplace(t *testing.T) {
doit := func(newNodeIsResponding, lastInBucketIsResponding bool) {
transport := newPingRecorder()
tab := newTable(transport, NodeID{}, &net.UDPAddr{}, "")
tab, _ := newTable(transport, NodeID{}, &net.UDPAddr{}, "")
defer tab.Close()
pingSender := newNode(MustHexID("a502af0f59b2aab7746995408c79e9ca312d2793cc997e44fc55eda62f0150bbb8c59a6f9269ba3a081518b62699ee807c7c19c20125ddfccca872608af9e370"), net.IP{}, 99, 99)
@ -177,7 +177,7 @@ func TestTable_closest(t *testing.T) {
test := func(test *closeTest) bool {
// for any node table, Target and N
tab := newTable(nil, test.Self, &net.UDPAddr{}, "")
tab, _ := newTable(nil, test.Self, &net.UDPAddr{}, "")
defer tab.Close()
tab.stuff(test.All)
@ -236,7 +236,7 @@ func TestTable_ReadRandomNodesGetAll(t *testing.T) {
},
}
test := func(buf []*Node) bool {
tab := newTable(nil, NodeID{}, &net.UDPAddr{}, "")
tab, _ := newTable(nil, NodeID{}, &net.UDPAddr{}, "")
defer tab.Close()
for i := 0; i < len(buf); i++ {
ld := cfg.Rand.Intn(len(tab.buckets))
@ -279,7 +279,7 @@ func (*closeTest) Generate(rand *rand.Rand, size int) reflect.Value {
func TestTable_Lookup(t *testing.T) {
self := nodeAtDistance(common.Hash{}, 0)
tab := newTable(lookupTestnet, self.ID, &net.UDPAddr{}, "")
tab, _ := newTable(lookupTestnet, self.ID, &net.UDPAddr{}, "")
defer tab.Close()
// lookup on empty table returns no nodes

View File

@ -200,12 +200,15 @@ func ListenUDP(priv *ecdsa.PrivateKey, laddr string, natm nat.Interface, nodeDBP
if err != nil {
return nil, err
}
tab, _ := newUDP(priv, conn, natm, nodeDBPath)
tab, _, err := newUDP(priv, conn, natm, nodeDBPath)
if err != nil {
return nil, err
}
glog.V(logger.Info).Infoln("Listening,", tab.self)
return tab, nil
}
func newUDP(priv *ecdsa.PrivateKey, c conn, natm nat.Interface, nodeDBPath string) (*Table, *udp) {
func newUDP(priv *ecdsa.PrivateKey, c conn, natm nat.Interface, nodeDBPath string) (*Table, *udp, error) {
udp := &udp{
conn: c,
priv: priv,
@ -225,10 +228,15 @@ func newUDP(priv *ecdsa.PrivateKey, c conn, natm nat.Interface, nodeDBPath strin
}
// TODO: separate TCP port
udp.ourEndpoint = makeEndpoint(realaddr, uint16(realaddr.Port))
udp.Table = newTable(udp, PubkeyID(&priv.PublicKey), realaddr, nodeDBPath)
tab, err := newTable(udp, PubkeyID(&priv.PublicKey), realaddr, nodeDBPath)
if err != nil {
return nil, nil, err
}
udp.Table = tab
go udp.loop()
go udp.readLoop()
return udp.Table, udp
return udp.Table, udp, nil
}
func (t *udp) close() {

View File

@ -69,7 +69,7 @@ func newUDPTest(t *testing.T) *udpTest {
remotekey: newkey(),
remoteaddr: &net.UDPAddr{IP: net.IP{1, 2, 3, 4}, Port: 30303},
}
test.table, test.udp = newUDP(test.localkey, test.pipe, nil, "")
test.table, test.udp, _ = newUDP(test.localkey, test.pipe, nil, "")
return test
}