github.com/ethw3/go-ethereuma@v0.0.0-20221013053120-c14602a4c23c/node/node.go (about)

     1  // Copyright 2015 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package node
    18  
    19  import (
    20  	crand "crypto/rand"
    21  	"errors"
    22  	"fmt"
    23  	"hash/crc32"
    24  	"net/http"
    25  	"os"
    26  	"path/filepath"
    27  	"reflect"
    28  	"strings"
    29  	"sync"
    30  
    31  	"github.com/ethw3/go-ethereuma/accounts"
    32  	"github.com/ethw3/go-ethereuma/common"
    33  	"github.com/ethw3/go-ethereuma/common/hexutil"
    34  	"github.com/ethw3/go-ethereuma/core/rawdb"
    35  	"github.com/ethw3/go-ethereuma/ethdb"
    36  	"github.com/ethw3/go-ethereuma/event"
    37  	"github.com/ethw3/go-ethereuma/log"
    38  	"github.com/ethw3/go-ethereuma/p2p"
    39  	"github.com/ethw3/go-ethereuma/rpc"
    40  	"github.com/prometheus/tsdb/fileutil"
    41  )
    42  
    43  // Node is a container on which services can be registered.
    44  type Node struct {
    45  	eventmux      *event.TypeMux
    46  	config        *Config
    47  	accman        *accounts.Manager
    48  	log           log.Logger
    49  	keyDir        string            // key store directory
    50  	keyDirTemp    bool              // If true, key directory will be removed by Stop
    51  	dirLock       fileutil.Releaser // prevents concurrent use of instance directory
    52  	stop          chan struct{}     // Channel to wait for termination notifications
    53  	server        *p2p.Server       // Currently running P2P networking layer
    54  	startStopLock sync.Mutex        // Start/Stop are protected by an additional lock
    55  	state         int               // Tracks state of node lifecycle
    56  
    57  	lock          sync.Mutex
    58  	lifecycles    []Lifecycle // All registered backends, services, and auxiliary services that have a lifecycle
    59  	rpcAPIs       []rpc.API   // List of APIs currently provided by the node
    60  	http          *httpServer //
    61  	ws            *httpServer //
    62  	httpAuth      *httpServer //
    63  	wsAuth        *httpServer //
    64  	ipc           *ipcServer  // Stores information about the ipc http server
    65  	inprocHandler *rpc.Server // In-process RPC request handler to process the API requests
    66  
    67  	databases map[*closeTrackingDB]struct{} // All open databases
    68  }
    69  
    70  const (
    71  	initializingState = iota
    72  	runningState
    73  	closedState
    74  )
    75  
    76  // New creates a new P2P node, ready for protocol registration.
    77  func New(conf *Config) (*Node, error) {
    78  	// Copy config and resolve the datadir so future changes to the current
    79  	// working directory don't affect the node.
    80  	confCopy := *conf
    81  	conf = &confCopy
    82  	if conf.DataDir != "" {
    83  		absdatadir, err := filepath.Abs(conf.DataDir)
    84  		if err != nil {
    85  			return nil, err
    86  		}
    87  		conf.DataDir = absdatadir
    88  	}
    89  	if conf.Logger == nil {
    90  		conf.Logger = log.New()
    91  	}
    92  
    93  	// Ensure that the instance name doesn't cause weird conflicts with
    94  	// other files in the data directory.
    95  	if strings.ContainsAny(conf.Name, `/\`) {
    96  		return nil, errors.New(`Config.Name must not contain '/' or '\'`)
    97  	}
    98  	if conf.Name == datadirDefaultKeyStore {
    99  		return nil, errors.New(`Config.Name cannot be "` + datadirDefaultKeyStore + `"`)
   100  	}
   101  	if strings.HasSuffix(conf.Name, ".ipc") {
   102  		return nil, errors.New(`Config.Name cannot end in ".ipc"`)
   103  	}
   104  
   105  	node := &Node{
   106  		config:        conf,
   107  		inprocHandler: rpc.NewServer(),
   108  		eventmux:      new(event.TypeMux),
   109  		log:           conf.Logger,
   110  		stop:          make(chan struct{}),
   111  		server:        &p2p.Server{Config: conf.P2P},
   112  		databases:     make(map[*closeTrackingDB]struct{}),
   113  	}
   114  
   115  	// Register built-in APIs.
   116  	node.rpcAPIs = append(node.rpcAPIs, node.apis()...)
   117  
   118  	// Acquire the instance directory lock.
   119  	if err := node.openDataDir(); err != nil {
   120  		return nil, err
   121  	}
   122  	keyDir, isEphem, err := getKeyStoreDir(conf)
   123  	if err != nil {
   124  		return nil, err
   125  	}
   126  	node.keyDir = keyDir
   127  	node.keyDirTemp = isEphem
   128  	// Creates an empty AccountManager with no backends. Callers (e.g. cmd/geth)
   129  	// are required to add the backends later on.
   130  	node.accman = accounts.NewManager(&accounts.Config{InsecureUnlockAllowed: conf.InsecureUnlockAllowed})
   131  
   132  	// Initialize the p2p server. This creates the node key and discovery databases.
   133  	node.server.Config.PrivateKey = node.config.NodeKey()
   134  	node.server.Config.Name = node.config.NodeName()
   135  	node.server.Config.Logger = node.log
   136  	if node.server.Config.StaticNodes == nil {
   137  		node.server.Config.StaticNodes = node.config.StaticNodes()
   138  	}
   139  	if node.server.Config.TrustedNodes == nil {
   140  		node.server.Config.TrustedNodes = node.config.TrustedNodes()
   141  	}
   142  	if node.server.Config.NodeDatabase == "" {
   143  		node.server.Config.NodeDatabase = node.config.NodeDB()
   144  	}
   145  
   146  	// Check HTTP/WS prefixes are valid.
   147  	if err := validatePrefix("HTTP", conf.HTTPPathPrefix); err != nil {
   148  		return nil, err
   149  	}
   150  	if err := validatePrefix("WebSocket", conf.WSPathPrefix); err != nil {
   151  		return nil, err
   152  	}
   153  
   154  	// Configure RPC servers.
   155  	node.http = newHTTPServer(node.log, conf.HTTPTimeouts)
   156  	node.httpAuth = newHTTPServer(node.log, conf.HTTPTimeouts)
   157  	node.ws = newHTTPServer(node.log, rpc.DefaultHTTPTimeouts)
   158  	node.wsAuth = newHTTPServer(node.log, rpc.DefaultHTTPTimeouts)
   159  	node.ipc = newIPCServer(node.log, conf.IPCEndpoint())
   160  
   161  	return node, nil
   162  }
   163  
   164  // Start starts all registered lifecycles, RPC services and p2p networking.
   165  // Node can only be started once.
   166  func (n *Node) Start() error {
   167  	n.startStopLock.Lock()
   168  	defer n.startStopLock.Unlock()
   169  
   170  	n.lock.Lock()
   171  	switch n.state {
   172  	case runningState:
   173  		n.lock.Unlock()
   174  		return ErrNodeRunning
   175  	case closedState:
   176  		n.lock.Unlock()
   177  		return ErrNodeStopped
   178  	}
   179  	n.state = runningState
   180  	// open networking and RPC endpoints
   181  	err := n.openEndpoints()
   182  	lifecycles := make([]Lifecycle, len(n.lifecycles))
   183  	copy(lifecycles, n.lifecycles)
   184  	n.lock.Unlock()
   185  
   186  	// Check if endpoint startup failed.
   187  	if err != nil {
   188  		n.doClose(nil)
   189  		return err
   190  	}
   191  	// Start all registered lifecycles.
   192  	var started []Lifecycle
   193  	for _, lifecycle := range lifecycles {
   194  		if err = lifecycle.Start(); err != nil {
   195  			break
   196  		}
   197  		started = append(started, lifecycle)
   198  	}
   199  	// Check if any lifecycle failed to start.
   200  	if err != nil {
   201  		n.stopServices(started)
   202  		n.doClose(nil)
   203  	}
   204  	return err
   205  }
   206  
   207  // Close stops the Node and releases resources acquired in
   208  // Node constructor New.
   209  func (n *Node) Close() error {
   210  	n.startStopLock.Lock()
   211  	defer n.startStopLock.Unlock()
   212  
   213  	n.lock.Lock()
   214  	state := n.state
   215  	n.lock.Unlock()
   216  	switch state {
   217  	case initializingState:
   218  		// The node was never started.
   219  		return n.doClose(nil)
   220  	case runningState:
   221  		// The node was started, release resources acquired by Start().
   222  		var errs []error
   223  		if err := n.stopServices(n.lifecycles); err != nil {
   224  			errs = append(errs, err)
   225  		}
   226  		return n.doClose(errs)
   227  	case closedState:
   228  		return ErrNodeStopped
   229  	default:
   230  		panic(fmt.Sprintf("node is in unknown state %d", state))
   231  	}
   232  }
   233  
   234  // doClose releases resources acquired by New(), collecting errors.
   235  func (n *Node) doClose(errs []error) error {
   236  	// Close databases. This needs the lock because it needs to
   237  	// synchronize with OpenDatabase*.
   238  	n.lock.Lock()
   239  	n.state = closedState
   240  	errs = append(errs, n.closeDatabases()...)
   241  	n.lock.Unlock()
   242  
   243  	if err := n.accman.Close(); err != nil {
   244  		errs = append(errs, err)
   245  	}
   246  	if n.keyDirTemp {
   247  		if err := os.RemoveAll(n.keyDir); err != nil {
   248  			errs = append(errs, err)
   249  		}
   250  	}
   251  
   252  	// Release instance directory lock.
   253  	n.closeDataDir()
   254  
   255  	// Unblock n.Wait.
   256  	close(n.stop)
   257  
   258  	// Report any errors that might have occurred.
   259  	switch len(errs) {
   260  	case 0:
   261  		return nil
   262  	case 1:
   263  		return errs[0]
   264  	default:
   265  		return fmt.Errorf("%v", errs)
   266  	}
   267  }
   268  
   269  // openEndpoints starts all network and RPC endpoints.
   270  func (n *Node) openEndpoints() error {
   271  	// start networking endpoints
   272  	n.log.Info("Starting peer-to-peer node", "instance", n.server.Name)
   273  	if err := n.server.Start(); err != nil {
   274  		return convertFileLockError(err)
   275  	}
   276  	// start RPC endpoints
   277  	err := n.startRPC()
   278  	if err != nil {
   279  		n.stopRPC()
   280  		n.server.Stop()
   281  	}
   282  	return err
   283  }
   284  
   285  // containsLifecycle checks if 'lfs' contains 'l'.
   286  func containsLifecycle(lfs []Lifecycle, l Lifecycle) bool {
   287  	for _, obj := range lfs {
   288  		if obj == l {
   289  			return true
   290  		}
   291  	}
   292  	return false
   293  }
   294  
   295  // stopServices terminates running services, RPC and p2p networking.
   296  // It is the inverse of Start.
   297  func (n *Node) stopServices(running []Lifecycle) error {
   298  	n.stopRPC()
   299  
   300  	// Stop running lifecycles in reverse order.
   301  	failure := &StopError{Services: make(map[reflect.Type]error)}
   302  	for i := len(running) - 1; i >= 0; i-- {
   303  		if err := running[i].Stop(); err != nil {
   304  			failure.Services[reflect.TypeOf(running[i])] = err
   305  		}
   306  	}
   307  
   308  	// Stop p2p networking.
   309  	n.server.Stop()
   310  
   311  	if len(failure.Services) > 0 {
   312  		return failure
   313  	}
   314  	return nil
   315  }
   316  
   317  func (n *Node) openDataDir() error {
   318  	if n.config.DataDir == "" {
   319  		return nil // ephemeral
   320  	}
   321  
   322  	instdir := filepath.Join(n.config.DataDir, n.config.name())
   323  	if err := os.MkdirAll(instdir, 0700); err != nil {
   324  		return err
   325  	}
   326  	// Lock the instance directory to prevent concurrent use by another instance as well as
   327  	// accidental use of the instance directory as a database.
   328  	release, _, err := fileutil.Flock(filepath.Join(instdir, "LOCK"))
   329  	if err != nil {
   330  		return convertFileLockError(err)
   331  	}
   332  	n.dirLock = release
   333  	return nil
   334  }
   335  
   336  func (n *Node) closeDataDir() {
   337  	// Release instance directory lock.
   338  	if n.dirLock != nil {
   339  		if err := n.dirLock.Release(); err != nil {
   340  			n.log.Error("Can't release datadir lock", "err", err)
   341  		}
   342  		n.dirLock = nil
   343  	}
   344  }
   345  
   346  // obtainJWTSecret loads the jwt-secret, either from the provided config,
   347  // or from the default location. If neither of those are present, it generates
   348  // a new secret and stores to the default location.
   349  func (n *Node) obtainJWTSecret(cliParam string) ([]byte, error) {
   350  	fileName := cliParam
   351  	if len(fileName) == 0 {
   352  		// no path provided, use default
   353  		fileName = n.ResolvePath(datadirJWTKey)
   354  	}
   355  	// try reading from file
   356  	if data, err := os.ReadFile(fileName); err == nil {
   357  		jwtSecret := common.FromHex(strings.TrimSpace(string(data)))
   358  		if len(jwtSecret) == 32 {
   359  			log.Info("Loaded JWT secret file", "path", fileName, "crc32", fmt.Sprintf("%#x", crc32.ChecksumIEEE(jwtSecret)))
   360  			return jwtSecret, nil
   361  		}
   362  		log.Error("Invalid JWT secret", "path", fileName, "length", len(jwtSecret))
   363  		return nil, errors.New("invalid JWT secret")
   364  	}
   365  	// Need to generate one
   366  	jwtSecret := make([]byte, 32)
   367  	crand.Read(jwtSecret)
   368  	// if we're in --dev mode, don't bother saving, just show it
   369  	if fileName == "" {
   370  		log.Info("Generated ephemeral JWT secret", "secret", hexutil.Encode(jwtSecret))
   371  		return jwtSecret, nil
   372  	}
   373  	if err := os.WriteFile(fileName, []byte(hexutil.Encode(jwtSecret)), 0600); err != nil {
   374  		return nil, err
   375  	}
   376  	log.Info("Generated JWT secret", "path", fileName)
   377  	return jwtSecret, nil
   378  }
   379  
   380  // startRPC is a helper method to configure all the various RPC endpoints during node
   381  // startup. It's not meant to be called at any time afterwards as it makes certain
   382  // assumptions about the state of the node.
   383  func (n *Node) startRPC() error {
   384  	if err := n.startInProc(); err != nil {
   385  		return err
   386  	}
   387  
   388  	// Configure IPC.
   389  	if n.ipc.endpoint != "" {
   390  		if err := n.ipc.start(n.rpcAPIs); err != nil {
   391  			return err
   392  		}
   393  	}
   394  	var (
   395  		servers   []*httpServer
   396  		open, all = n.GetAPIs()
   397  	)
   398  
   399  	initHttp := func(server *httpServer, apis []rpc.API, port int) error {
   400  		if err := server.setListenAddr(n.config.HTTPHost, port); err != nil {
   401  			return err
   402  		}
   403  		if err := server.enableRPC(apis, httpConfig{
   404  			CorsAllowedOrigins: n.config.HTTPCors,
   405  			Vhosts:             n.config.HTTPVirtualHosts,
   406  			Modules:            n.config.HTTPModules,
   407  			prefix:             n.config.HTTPPathPrefix,
   408  		}); err != nil {
   409  			return err
   410  		}
   411  		servers = append(servers, server)
   412  		return nil
   413  	}
   414  
   415  	initWS := func(apis []rpc.API, port int) error {
   416  		server := n.wsServerForPort(port, false)
   417  		if err := server.setListenAddr(n.config.WSHost, port); err != nil {
   418  			return err
   419  		}
   420  		if err := server.enableWS(n.rpcAPIs, wsConfig{
   421  			Modules: n.config.WSModules,
   422  			Origins: n.config.WSOrigins,
   423  			prefix:  n.config.WSPathPrefix,
   424  		}); err != nil {
   425  			return err
   426  		}
   427  		servers = append(servers, server)
   428  		return nil
   429  	}
   430  
   431  	initAuth := func(apis []rpc.API, port int, secret []byte) error {
   432  		// Enable auth via HTTP
   433  		server := n.httpAuth
   434  		if err := server.setListenAddr(n.config.AuthAddr, port); err != nil {
   435  			return err
   436  		}
   437  		if err := server.enableRPC(apis, httpConfig{
   438  			CorsAllowedOrigins: DefaultAuthCors,
   439  			Vhosts:             n.config.AuthVirtualHosts,
   440  			Modules:            DefaultAuthModules,
   441  			prefix:             DefaultAuthPrefix,
   442  			jwtSecret:          secret,
   443  		}); err != nil {
   444  			return err
   445  		}
   446  		servers = append(servers, server)
   447  		// Enable auth via WS
   448  		server = n.wsServerForPort(port, true)
   449  		if err := server.setListenAddr(n.config.AuthAddr, port); err != nil {
   450  			return err
   451  		}
   452  		if err := server.enableWS(apis, wsConfig{
   453  			Modules:   DefaultAuthModules,
   454  			Origins:   DefaultAuthOrigins,
   455  			prefix:    DefaultAuthPrefix,
   456  			jwtSecret: secret,
   457  		}); err != nil {
   458  			return err
   459  		}
   460  		servers = append(servers, server)
   461  		return nil
   462  	}
   463  
   464  	// Set up HTTP.
   465  	if n.config.HTTPHost != "" {
   466  		// Configure legacy unauthenticated HTTP.
   467  		if err := initHttp(n.http, open, n.config.HTTPPort); err != nil {
   468  			return err
   469  		}
   470  	}
   471  	// Configure WebSocket.
   472  	if n.config.WSHost != "" {
   473  		// legacy unauthenticated
   474  		if err := initWS(open, n.config.WSPort); err != nil {
   475  			return err
   476  		}
   477  	}
   478  	// Configure authenticated API
   479  	if len(open) != len(all) {
   480  		jwtSecret, err := n.obtainJWTSecret(n.config.JWTSecret)
   481  		if err != nil {
   482  			return err
   483  		}
   484  		if err := initAuth(all, n.config.AuthPort, jwtSecret); err != nil {
   485  			return err
   486  		}
   487  	}
   488  	// Start the servers
   489  	for _, server := range servers {
   490  		if err := server.start(); err != nil {
   491  			return err
   492  		}
   493  	}
   494  	return nil
   495  }
   496  
   497  func (n *Node) wsServerForPort(port int, authenticated bool) *httpServer {
   498  	httpServer, wsServer := n.http, n.ws
   499  	if authenticated {
   500  		httpServer, wsServer = n.httpAuth, n.wsAuth
   501  	}
   502  	if n.config.HTTPHost == "" || httpServer.port == port {
   503  		return httpServer
   504  	}
   505  	return wsServer
   506  }
   507  
   508  func (n *Node) stopRPC() {
   509  	n.http.stop()
   510  	n.ws.stop()
   511  	n.httpAuth.stop()
   512  	n.wsAuth.stop()
   513  	n.ipc.stop()
   514  	n.stopInProc()
   515  }
   516  
   517  // startInProc registers all RPC APIs on the inproc server.
   518  func (n *Node) startInProc() error {
   519  	for _, api := range n.rpcAPIs {
   520  		if err := n.inprocHandler.RegisterName(api.Namespace, api.Service); err != nil {
   521  			return err
   522  		}
   523  	}
   524  	return nil
   525  }
   526  
   527  // stopInProc terminates the in-process RPC endpoint.
   528  func (n *Node) stopInProc() {
   529  	n.inprocHandler.Stop()
   530  }
   531  
   532  // Wait blocks until the node is closed.
   533  func (n *Node) Wait() {
   534  	<-n.stop
   535  }
   536  
   537  // RegisterLifecycle registers the given Lifecycle on the node.
   538  func (n *Node) RegisterLifecycle(lifecycle Lifecycle) {
   539  	n.lock.Lock()
   540  	defer n.lock.Unlock()
   541  
   542  	if n.state != initializingState {
   543  		panic("can't register lifecycle on running/stopped node")
   544  	}
   545  	if containsLifecycle(n.lifecycles, lifecycle) {
   546  		panic(fmt.Sprintf("attempt to register lifecycle %T more than once", lifecycle))
   547  	}
   548  	n.lifecycles = append(n.lifecycles, lifecycle)
   549  }
   550  
   551  // RegisterProtocols adds backend's protocols to the node's p2p server.
   552  func (n *Node) RegisterProtocols(protocols []p2p.Protocol) {
   553  	n.lock.Lock()
   554  	defer n.lock.Unlock()
   555  
   556  	if n.state != initializingState {
   557  		panic("can't register protocols on running/stopped node")
   558  	}
   559  	n.server.Protocols = append(n.server.Protocols, protocols...)
   560  }
   561  
   562  // RegisterAPIs registers the APIs a service provides on the node.
   563  func (n *Node) RegisterAPIs(apis []rpc.API) {
   564  	n.lock.Lock()
   565  	defer n.lock.Unlock()
   566  
   567  	if n.state != initializingState {
   568  		panic("can't register APIs on running/stopped node")
   569  	}
   570  	n.rpcAPIs = append(n.rpcAPIs, apis...)
   571  }
   572  
   573  // GetAPIs return two sets of APIs, both the ones that do not require
   574  // authentication, and the complete set
   575  func (n *Node) GetAPIs() (unauthenticated, all []rpc.API) {
   576  	for _, api := range n.rpcAPIs {
   577  		if !api.Authenticated {
   578  			unauthenticated = append(unauthenticated, api)
   579  		}
   580  	}
   581  	return unauthenticated, n.rpcAPIs
   582  }
   583  
   584  // RegisterHandler mounts a handler on the given path on the canonical HTTP server.
   585  //
   586  // The name of the handler is shown in a log message when the HTTP server starts
   587  // and should be a descriptive term for the service provided by the handler.
   588  func (n *Node) RegisterHandler(name, path string, handler http.Handler) {
   589  	n.lock.Lock()
   590  	defer n.lock.Unlock()
   591  
   592  	if n.state != initializingState {
   593  		panic("can't register HTTP handler on running/stopped node")
   594  	}
   595  
   596  	n.http.mux.Handle(path, handler)
   597  	n.http.handlerNames[path] = name
   598  }
   599  
   600  // Attach creates an RPC client attached to an in-process API handler.
   601  func (n *Node) Attach() (*rpc.Client, error) {
   602  	return rpc.DialInProc(n.inprocHandler), nil
   603  }
   604  
   605  // RPCHandler returns the in-process RPC request handler.
   606  func (n *Node) RPCHandler() (*rpc.Server, error) {
   607  	n.lock.Lock()
   608  	defer n.lock.Unlock()
   609  
   610  	if n.state == closedState {
   611  		return nil, ErrNodeStopped
   612  	}
   613  	return n.inprocHandler, nil
   614  }
   615  
   616  // Config returns the configuration of node.
   617  func (n *Node) Config() *Config {
   618  	return n.config
   619  }
   620  
   621  // Server retrieves the currently running P2P network layer. This method is meant
   622  // only to inspect fields of the currently running server. Callers should not
   623  // start or stop the returned server.
   624  func (n *Node) Server() *p2p.Server {
   625  	n.lock.Lock()
   626  	defer n.lock.Unlock()
   627  
   628  	return n.server
   629  }
   630  
   631  // DataDir retrieves the current datadir used by the protocol stack.
   632  // Deprecated: No files should be stored in this directory, use InstanceDir instead.
   633  func (n *Node) DataDir() string {
   634  	return n.config.DataDir
   635  }
   636  
   637  // InstanceDir retrieves the instance directory used by the protocol stack.
   638  func (n *Node) InstanceDir() string {
   639  	return n.config.instanceDir()
   640  }
   641  
   642  // KeyStoreDir retrieves the key directory
   643  func (n *Node) KeyStoreDir() string {
   644  	return n.keyDir
   645  }
   646  
   647  // AccountManager retrieves the account manager used by the protocol stack.
   648  func (n *Node) AccountManager() *accounts.Manager {
   649  	return n.accman
   650  }
   651  
   652  // IPCEndpoint retrieves the current IPC endpoint used by the protocol stack.
   653  func (n *Node) IPCEndpoint() string {
   654  	return n.ipc.endpoint
   655  }
   656  
   657  // HTTPEndpoint returns the URL of the HTTP server. Note that this URL does not
   658  // contain the JSON-RPC path prefix set by HTTPPathPrefix.
   659  func (n *Node) HTTPEndpoint() string {
   660  	return "http://" + n.http.listenAddr()
   661  }
   662  
   663  // WSEndpoint returns the current JSON-RPC over WebSocket endpoint.
   664  func (n *Node) WSEndpoint() string {
   665  	if n.http.wsAllowed() {
   666  		return "ws://" + n.http.listenAddr() + n.http.wsConfig.prefix
   667  	}
   668  	return "ws://" + n.ws.listenAddr() + n.ws.wsConfig.prefix
   669  }
   670  
   671  // EventMux retrieves the event multiplexer used by all the network services in
   672  // the current protocol stack.
   673  func (n *Node) EventMux() *event.TypeMux {
   674  	return n.eventmux
   675  }
   676  
   677  // OpenDatabase opens an existing database with the given name (or creates one if no
   678  // previous can be found) from within the node's instance directory. If the node is
   679  // ephemeral, a memory database is returned.
   680  func (n *Node) OpenDatabase(name string, cache, handles int, namespace string, readonly bool) (ethdb.Database, error) {
   681  	n.lock.Lock()
   682  	defer n.lock.Unlock()
   683  	if n.state == closedState {
   684  		return nil, ErrNodeStopped
   685  	}
   686  
   687  	var db ethdb.Database
   688  	var err error
   689  	if n.config.DataDir == "" {
   690  		db = rawdb.NewMemoryDatabase()
   691  	} else {
   692  		db, err = rawdb.NewLevelDBDatabase(n.ResolvePath(name), cache, handles, namespace, readonly)
   693  	}
   694  
   695  	if err == nil {
   696  		db = n.wrapDatabase(db)
   697  	}
   698  	return db, err
   699  }
   700  
   701  // OpenDatabaseWithFreezer opens an existing database with the given name (or
   702  // creates one if no previous can be found) from within the node's data directory,
   703  // also attaching a chain freezer to it that moves ancient chain data from the
   704  // database to immutable append-only files. If the node is an ephemeral one, a
   705  // memory database is returned.
   706  func (n *Node) OpenDatabaseWithFreezer(name string, cache, handles int, ancient string, namespace string, readonly bool) (ethdb.Database, error) {
   707  	n.lock.Lock()
   708  	defer n.lock.Unlock()
   709  	if n.state == closedState {
   710  		return nil, ErrNodeStopped
   711  	}
   712  
   713  	var db ethdb.Database
   714  	var err error
   715  	if n.config.DataDir == "" {
   716  		db = rawdb.NewMemoryDatabase()
   717  	} else {
   718  		db, err = rawdb.NewLevelDBDatabaseWithFreezer(n.ResolvePath(name), cache, handles, n.ResolveAncient(name, ancient), namespace, readonly)
   719  	}
   720  
   721  	if err == nil {
   722  		db = n.wrapDatabase(db)
   723  	}
   724  	return db, err
   725  }
   726  
   727  // ResolvePath returns the absolute path of a resource in the instance directory.
   728  func (n *Node) ResolvePath(x string) string {
   729  	return n.config.ResolvePath(x)
   730  }
   731  
   732  // ResolveAncient returns the absolute path of the root ancient directory.
   733  func (n *Node) ResolveAncient(name string, ancient string) string {
   734  	switch {
   735  	case ancient == "":
   736  		ancient = filepath.Join(n.ResolvePath(name), "ancient")
   737  	case !filepath.IsAbs(ancient):
   738  		ancient = n.ResolvePath(ancient)
   739  	}
   740  	return ancient
   741  }
   742  
   743  // closeTrackingDB wraps the Close method of a database. When the database is closed by the
   744  // service, the wrapper removes it from the node's database map. This ensures that Node
   745  // won't auto-close the database if it is closed by the service that opened it.
   746  type closeTrackingDB struct {
   747  	ethdb.Database
   748  	n *Node
   749  }
   750  
   751  func (db *closeTrackingDB) Close() error {
   752  	db.n.lock.Lock()
   753  	delete(db.n.databases, db)
   754  	db.n.lock.Unlock()
   755  	return db.Database.Close()
   756  }
   757  
   758  // wrapDatabase ensures the database will be auto-closed when Node is closed.
   759  func (n *Node) wrapDatabase(db ethdb.Database) ethdb.Database {
   760  	wrapper := &closeTrackingDB{db, n}
   761  	n.databases[wrapper] = struct{}{}
   762  	return wrapper
   763  }
   764  
   765  // closeDatabases closes all open databases.
   766  func (n *Node) closeDatabases() (errors []error) {
   767  	for db := range n.databases {
   768  		delete(n.databases, db)
   769  		if err := db.Database.Close(); err != nil {
   770  			errors = append(errors, err)
   771  		}
   772  	}
   773  	return errors
   774  }