go-ethereum/node/node.go
Felix Lange 3750d835a1 internal/debug: APIs for profiling and tracing
The debug package provides an RPC wrapper for glog settings and the
debugging facilities of the Go runtime. They can be triggered through
both command line flags and the IPC listener.
2016-01-28 13:36:11 +01:00

307 lines
8.4 KiB
Go

// 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"
"reflect"
"sync"
"syscall"
"github.com/ethereum/go-ethereum/event"
"github.com/ethereum/go-ethereum/internal/debug"
"github.com/ethereum/go-ethereum/p2p"
"github.com/ethereum/go-ethereum/rpc"
)
var (
ErrDatadirUsed = errors.New("datadir already used")
ErrNodeStopped = errors.New("node not started")
ErrNodeRunning = errors.New("node already running")
ErrServiceUnknown = errors.New("unknown service")
datadirInUseErrnos = map[uint]bool{11: true, 32: true, 35: true}
)
// Node represents a P2P node into which arbitrary (uniquely typed) services might
// be registered.
type Node struct {
datadir string // Path to the currently used data directory
eventmux *event.TypeMux // Event multiplexer used between the services of a stack
serverConfig *p2p.Server // Configuration of the underlying P2P networking layer
server *p2p.Server // Currently running P2P networking layer
serviceFuncs []ServiceConstructor // Service constructors (in dependency order)
services map[reflect.Type]Service // Currently running services
stop chan struct{} // Channel to wait for termination notifications
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,
serverConfig: &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,
},
serviceFuncs: []ServiceConstructor{},
eventmux: new(event.TypeMux),
}, nil
}
// Register injects a new service into the node's stack. The service created by
// the passed constructor must be unique in its type with regard to sibling ones.
func (n *Node) Register(constructor ServiceConstructor) error {
n.lock.Lock()
defer n.lock.Unlock()
if n.server != nil {
return ErrNodeRunning
}
n.serviceFuncs = append(n.serviceFuncs, constructor)
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.server != nil {
return ErrNodeRunning
}
// Otherwise copy and specialize the P2P configuration
running := new(p2p.Server)
*running = *n.serverConfig
services := make(map[reflect.Type]Service)
for _, constructor := range n.serviceFuncs {
// Create a new context for the particular service
ctx := &ServiceContext{
datadir: n.datadir,
services: make(map[reflect.Type]Service),
EventMux: n.eventmux,
}
for kind, s := range services { // copy needed for threaded access
ctx.services[kind] = s
}
// Construct and save the service
service, err := constructor(ctx)
if err != nil {
return err
}
kind := reflect.TypeOf(service)
if _, exists := services[kind]; exists {
return &DuplicateServiceError{Kind: kind}
}
services[kind] = 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 := []reflect.Type{}
for kind, service := range services {
// Start the next service, stopping all previous upon failure
if err := service.Start(running); err != nil {
for _, kind := range started {
services[kind].Stop()
}
running.Stop()
return err
}
// Mark the service started for potential cleanup
started = append(started, kind)
}
// Finish initializing the startup
n.services = services
n.server = running
n.stop = make(chan struct{})
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.server == nil {
return ErrNodeStopped
}
// Otherwise terminate all the services and the P2P server too
failure := &StopError{
Services: make(map[reflect.Type]error),
}
for kind, service := range n.services {
if err := service.Stop(); err != nil {
failure.Services[kind] = err
}
}
n.server.Stop()
n.services = nil
n.server = nil
close(n.stop)
if len(failure.Services) > 0 {
return failure
}
return nil
}
// Wait blocks the thread until the node is stopped. If the node is not running
// at the time of invocation, the method immediately returns.
func (n *Node) Wait() {
n.lock.RLock()
if n.server == nil {
return
}
stop := n.stop
n.lock.RUnlock()
<-stop
}
// 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.server
}
// Service retrieves a currently running service registered of a specific type.
func (n *Node) Service(service interface{}) error {
n.lock.RLock()
defer n.lock.RUnlock()
// Short circuit if the node's not running
if n.server == nil {
return ErrNodeStopped
}
// Otherwise try to find the service to return
element := reflect.ValueOf(service).Elem()
if running, ok := n.services[element.Type()]; ok {
element.Set(reflect.ValueOf(running))
return nil
}
return ErrServiceUnknown
}
// 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.eventmux
}
// APIs returns the collection of RPC descriptor this node offers. This method
// is just a quick placeholder passthrough for the RPC update, which in the next
// step will be fully integrated into the node itself.
func (n *Node) APIs() []rpc.API {
// Define all the APIs owned by the node itself
apis := []rpc.API{
{
Namespace: "admin",
Version: "1.0",
Service: NewPrivateAdminAPI(n),
}, {
Namespace: "admin",
Version: "1.0",
Service: NewPublicAdminAPI(n),
Public: true,
}, {
Namespace: "debug",
Version: "1.0",
Service: debug.Handler,
}, {
Namespace: "debug",
Version: "1.0",
Service: NewPublicDebugAPI(n),
Public: true,
}, {
Namespace: "web3",
Version: "1.0",
Service: NewPublicWeb3API(n),
Public: true,
},
}
// Inject all the APIs owned by various services
for _, api := range n.services {
apis = append(apis, api.APIs()...)
}
return apis
}