Merge pull request #1934 from karalabe/polish-protocol-infos

eth, p2p, rpc/api: polish protocol info gathering

11 files changed, 208 insertions, 85 deletions

diff --git a/eth/backend.go b/eth/backend.go
index 0683705df..9eb211e31 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -467,62 +467,10 @@ func New(config *Config) (*Ethereum, error) {
 	return eth, nil
 }
 
-type NodeInfo struct {
-	Name       string
-	NodeUrl    string
-	NodeID     string
-	IP         string
-	DiscPort   int // UDP listening port for discovery protocol
-	TCPPort    int // TCP listening port for RLPx
-	Td         string
-	ListenAddr string
-}
-
-func (s *Ethereum) NodeInfo() *NodeInfo {
-	node := s.net.Self()
-
-	return &NodeInfo{
-		Name:       s.Name(),
-		NodeUrl:    node.String(),
-		NodeID:     node.ID.String(),
-		IP:         node.IP.String(),
-		DiscPort:   int(node.UDP),
-		TCPPort:    int(node.TCP),
-		ListenAddr: s.net.ListenAddr,
-		Td:         s.BlockChain().GetTd(s.BlockChain().CurrentBlock().Hash()).String(),
-	}
-}
-
-type PeerInfo struct {
-	ID            string
-	Name          string
-	Caps          string
-	RemoteAddress string
-	LocalAddress  string
-}
-
-func newPeerInfo(peer *p2p.Peer) *PeerInfo {
-	var caps []string
-	for _, cap := range peer.Caps() {
-		caps = append(caps, cap.String())
-	}
-	return &PeerInfo{
-		ID:            peer.ID().String(),
-		Name:          peer.Name(),
-		Caps:          strings.Join(caps, ", "),
-		RemoteAddress: peer.RemoteAddr().String(),
-		LocalAddress:  peer.LocalAddr().String(),
-	}
-}
-
-// PeersInfo returns an array of PeerInfo objects describing connected peers
-func (s *Ethereum) PeersInfo() (peersinfo []*PeerInfo) {
-	for _, peer := range s.net.Peers() {
-		if peer != nil {
-			peersinfo = append(peersinfo, newPeerInfo(peer))
-		}
-	}
-	return
+// Network retrieves the underlying P2P network server. This should eventually
+// be moved out into a protocol independent package, but for now use an accessor.
+func (s *Ethereum) Network() *p2p.Server {
+	return s.net
 }
 
 func (s *Ethereum) ResetWithGenesisBlock(gb *types.Block) {
diff --git a/eth/handler.go b/eth/handler.go
index 7dc7de80e..d8c5b4b64 100644
--- a/eth/handler.go
+++ b/eth/handler.go
@@ -34,6 +34,7 @@ import (
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/logger/glog"
 	"github.com/ethereum/go-ethereum/p2p"
+	"github.com/ethereum/go-ethereum/p2p/discover"
 	"github.com/ethereum/go-ethereum/pow"
 	"github.com/ethereum/go-ethereum/rlp"
 )
@@ -55,6 +56,8 @@ type hashFetcherFn func(common.Hash) error
 type blockFetcherFn func([]common.Hash) error
 
 type ProtocolManager struct {
+	networkId int
+
 	fastSync   bool
 	txpool     txPool
 	blockchain *core.BlockChain
@@ -91,6 +94,7 @@ func NewProtocolManager(fastSync bool, networkId int, mux *event.TypeMux, txpool
 	}
 	// Create the protocol manager with the base fields
 	manager := &ProtocolManager{
+		networkId:  networkId,
 		fastSync:   fastSync,
 		eventMux:   mux,
 		txpool:     txpool,
@@ -111,14 +115,23 @@ func NewProtocolManager(fastSync bool, networkId int, mux *event.TypeMux, txpool
 		// Compatible; initialise the sub-protocol
 		version := version // Closure for the run
 		manager.SubProtocols = append(manager.SubProtocols, p2p.Protocol{
-			Name:    "eth",
+			Name:    ProtocolName,
 			Version: version,
 			Length:  ProtocolLengths[i],
 			Run: func(p *p2p.Peer, rw p2p.MsgReadWriter) error {
-				peer := manager.newPeer(int(version), networkId, p, rw)
+				peer := manager.newPeer(int(version), p, rw)
 				manager.newPeerCh <- peer
 				return manager.handle(peer)
 			},
+			NodeInfo: func() interface{} {
+				return manager.NodeInfo()
+			},
+			PeerInfo: func(id discover.NodeID) interface{} {
+				if p := manager.peers.Peer(fmt.Sprintf("%x", id[:8])); p != nil {
+					return p.Info()
+				}
+				return nil
+			},
 		})
 	}
 	if len(manager.SubProtocols) == 0 {
@@ -188,8 +201,8 @@ func (pm *ProtocolManager) Stop() {
 	glog.V(logger.Info).Infoln("Ethereum protocol handler stopped")
 }
 
-func (pm *ProtocolManager) newPeer(pv, nv int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
-	return newPeer(pv, nv, p, newMeteredMsgWriter(rw))
+func (pm *ProtocolManager) newPeer(pv int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
+	return newPeer(pv, p, newMeteredMsgWriter(rw))
 }
 
 // handle is the callback invoked to manage the life cycle of an eth peer. When
@@ -199,7 +212,7 @@ func (pm *ProtocolManager) handle(p *peer) error {
 
 	// Execute the Ethereum handshake
 	td, head, genesis := pm.blockchain.Status()
-	if err := p.Handshake(td, head, genesis); err != nil {
+	if err := p.Handshake(pm.networkId, td, head, genesis); err != nil {
 		glog.V(logger.Debug).Infof("%v: handshake failed: %v", p, err)
 		return err
 	}
@@ -730,3 +743,22 @@ func (self *ProtocolManager) txBroadcastLoop() {
 		self.BroadcastTx(event.Tx.Hash(), event.Tx)
 	}
 }
+
+// EthNodeInfo represents a short summary of the Ethereum sub-protocol metadata known
+// about the host peer.
+type EthNodeInfo struct {
+	Network    int      `json:"network"`    // Ethereum network ID (0=Olympic, 1=Frontier, 2=Morden)
+	Difficulty *big.Int `json:"difficulty"` // Total difficulty of the host's blockchain
+	Genesis    string   `json:"genesis"`    // SHA3 hash of the host's genesis block
+	Head       string   `json:"head"`       // SHA3 hash of the host's best owned block
+}
+
+// NodeInfo retrieves some protocol metadata about the running host node.
+func (self *ProtocolManager) NodeInfo() *EthNodeInfo {
+	return &EthNodeInfo{
+		Network:    self.networkId,
+		Difficulty: self.blockchain.GetTd(self.blockchain.CurrentBlock().Hash()),
+		Genesis:    fmt.Sprintf("%x", self.blockchain.Genesis().Hash()),
+		Head:       fmt.Sprintf("%x", self.blockchain.CurrentBlock().Hash()),
+	}
+}
diff --git a/eth/helper_test.go b/eth/helper_test.go
index 16907be8b..65fccf7b4 100644
--- a/eth/helper_test.go
+++ b/eth/helper_test.go
@@ -117,7 +117,7 @@ func newTestPeer(name string, version int, pm *ProtocolManager, shake bool) (*te
 	var id discover.NodeID
 	rand.Read(id[:])
 
-	peer := pm.newPeer(version, NetworkId, p2p.NewPeer(id, name, nil), net)
+	peer := pm.newPeer(version, p2p.NewPeer(id, name, nil), net)
 
 	// Start the peer on a new thread
 	errc := make(chan error, 1)
diff --git a/eth/peer.go b/eth/peer.go
index 695e910f6..15ba22ff5 100644
--- a/eth/peer.go
+++ b/eth/peer.go
@@ -44,38 +44,51 @@ const (
 	handshakeTimeout = 5 * time.Second
 )
 
+// PeerInfo represents a short summary of the Ethereum sub-protocol metadata known
+// about a connected peer.
+type PeerInfo struct {
+	Version    int      `json:"version"`    // Ethereum protocol version negotiated
+	Difficulty *big.Int `json:"difficulty"` // Total difficulty of the peer's blockchain
+	Head       string   `json:"head"`       // SHA3 hash of the peer's best owned block
+}
+
 type peer struct {
-	*p2p.Peer
+	id string
 
+	*p2p.Peer
 	rw p2p.MsgReadWriter
 
 	version int // Protocol version negotiated
-	network int // Network ID being on
-
-	id string
-
-	head common.Hash
-	td   *big.Int
-	lock sync.RWMutex
+	head    common.Hash
+	td      *big.Int
+	lock    sync.RWMutex
 
 	knownTxs    *set.Set // Set of transaction hashes known to be known by this peer
 	knownBlocks *set.Set // Set of block hashes known to be known by this peer
 }
 
-func newPeer(version, network int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
+func newPeer(version int, p *p2p.Peer, rw p2p.MsgReadWriter) *peer {
 	id := p.ID()
 
 	return &peer{
 		Peer:        p,
 		rw:          rw,
 		version:     version,
-		network:     network,
 		id:          fmt.Sprintf("%x", id[:8]),
 		knownTxs:    set.New(),
 		knownBlocks: set.New(),
 	}
 }
 
+// Info gathers and returns a collection of metadata known about a peer.
+func (p *peer) Info() *PeerInfo {
+	return &PeerInfo{
+		Version:    p.version,
+		Difficulty: p.Td(),
+		Head:       fmt.Sprintf("%x", p.Head()),
+	}
+}
+
 // Head retrieves a copy of the current head (most recent) hash of the peer.
 func (p *peer) Head() (hash common.Hash) {
 	p.lock.RLock()
@@ -268,20 +281,22 @@ func (p *peer) RequestReceipts(hashes []common.Hash) error {
 
 // Handshake executes the eth protocol handshake, negotiating version number,
 // network IDs, difficulties, head and genesis blocks.
-func (p *peer) Handshake(td *big.Int, head common.Hash, genesis common.Hash) error {
+func (p *peer) Handshake(network int, td *big.Int, head common.Hash, genesis common.Hash) error {
+	// Send out own handshake in a new thread
 	errc := make(chan error, 2)
 	var status statusData // safe to read after two values have been received from errc
+
 	go func() {
 		errc <- p2p.Send(p.rw, StatusMsg, &statusData{
 			ProtocolVersion: uint32(p.version),
-			NetworkId:       uint32(p.network),
+			NetworkId:       uint32(network),
 			TD:              td,
 			CurrentBlock:    head,
 			GenesisBlock:    genesis,
 		})
 	}()
 	go func() {
-		errc <- p.readStatus(&status, genesis)
+		errc <- p.readStatus(network, &status, genesis)
 	}()
 	timeout := time.NewTimer(handshakeTimeout)
 	defer timeout.Stop()
@@ -299,7 +314,7 @@ func (p *peer) Handshake(td *big.Int, head common.Hash, genesis common.Hash) err
 	return nil
 }
 
-func (p *peer) readStatus(status *statusData, genesis common.Hash) (err error) {
+func (p *peer) readStatus(network int, status *statusData, genesis common.Hash) (err error) {
 	msg, err := p.rw.ReadMsg()
 	if err != nil {
 		return err
@@ -317,8 +332,8 @@ func (p *peer) readStatus(status *statusData, genesis common.Hash) (err error) {
 	if status.GenesisBlock != genesis {
 		return errResp(ErrGenesisBlockMismatch, "%x (!= %x)", status.GenesisBlock, genesis)
 	}
-	if int(status.NetworkId) != p.network {
-		return errResp(ErrNetworkIdMismatch, "%d (!= %d)", status.NetworkId, p.network)
+	if int(status.NetworkId) != network {
+		return errResp(ErrNetworkIdMismatch, "%d (!= %d)", status.NetworkId, network)
 	}
 	if int(status.ProtocolVersion) != p.version {
 		return errResp(ErrProtocolVersionMismatch, "%d (!= %d)", status.ProtocolVersion, p.version)
diff --git a/eth/protocol.go b/eth/protocol.go
index 410347ed3..808ac0601 100644
--- a/eth/protocol.go
+++ b/eth/protocol.go
@@ -33,6 +33,9 @@ const (
 	eth63 = 63
 )
 
+// Official short name of the protocol used during capability negotiation.
+var ProtocolName = "eth"
+
 // Supported versions of the eth protocol (first is primary).
 var ProtocolVersions = []uint{eth63, eth62, eth61}
 
diff --git a/eth/sync_test.go b/eth/sync_test.go
index f3a6718ab..afd90c9b6 100644
--- a/eth/sync_test.go
+++ b/eth/sync_test.go
@@ -40,8 +40,8 @@ func TestFastSyncDisabling(t *testing.T) {
 	// Sync up the two peers
 	io1, io2 := p2p.MsgPipe()
 
-	go pmFull.handle(pmFull.newPeer(63, NetworkId, p2p.NewPeer(discover.NodeID{}, "empty", nil), io2))
-	go pmEmpty.handle(pmEmpty.newPeer(63, NetworkId, p2p.NewPeer(discover.NodeID{}, "full", nil), io1))
+	go pmFull.handle(pmFull.newPeer(63, p2p.NewPeer(discover.NodeID{}, "empty", nil), io2))
+	go pmEmpty.handle(pmEmpty.newPeer(63, p2p.NewPeer(discover.NodeID{}, "full", nil), io1))
 
 	time.Sleep(250 * time.Millisecond)
 	pmEmpty.synchronise(pmEmpty.peers.BestPeer())
diff --git a/p2p/peer.go b/p2p/peer.go
index 1b3b19c79..72ed4069c 100644
--- a/p2p/peer.go
+++ b/p2p/peer.go
@@ -359,3 +359,49 @@ func (rw *protoRW) ReadMsg() (Msg, error) {
 		return Msg{}, io.EOF
 	}
 }
+
+// PeerInfo represents a short summary of the information known about a connected
+// peer. Sub-protocol independent fields are contained and initialized here, with
+// protocol specifics delegated to all connected sub-protocols.
+type PeerInfo struct {
+	ID      string   `json:"id"`   // Unique node identifier (also the encryption key)
+	Name    string   `json:"name"` // Name of the node, including client type, version, OS, custom data
+	Caps    []string `json:"caps"` // Sum-protocols advertised by this particular peer
+	Network struct {
+		LocalAddress  string `json:"localAddress"`  // Local endpoint of the TCP data connection
+		RemoteAddress string `json:"remoteAddress"` // Remote endpoint of the TCP data connection
+	} `json:"network"`
+	Protocols map[string]interface{} `json:"protocols"` // Sub-protocol specific metadata fields
+}
+
+// Info gathers and returns a collection of metadata known about a peer.
+func (p *Peer) Info() *PeerInfo {
+	// Gather the protocol capabilities
+	var caps []string
+	for _, cap := range p.Caps() {
+		caps = append(caps, cap.String())
+	}
+	// Assemble the generic peer metadata
+	info := &PeerInfo{
+		ID:        p.ID().String(),
+		Name:      p.Name(),
+		Caps:      caps,
+		Protocols: make(map[string]interface{}),
+	}
+	info.Network.LocalAddress = p.LocalAddr().String()
+	info.Network.RemoteAddress = p.RemoteAddr().String()
+
+	// Gather all the running protocol infos
+	for _, proto := range p.running {
+		protoInfo := interface{}("unknown")
+		if query := proto.Protocol.PeerInfo; query != nil {
+			if metadata := query(p.ID()); metadata != nil {
+				protoInfo = metadata
+			} else {
+				protoInfo = "handshake"
+			}
+		}
+		info.Protocols[proto.Name] = protoInfo
+	}
+	return info
+}
diff --git a/p2p/protocol.go b/p2p/protocol.go
index ac0c3d942..ee747ba23 100644
--- a/p2p/protocol.go
+++ b/p2p/protocol.go
@@ -16,7 +16,11 @@
 
 package p2p
 
-import "fmt"
+import (
+	"fmt"
+
+	"github.com/ethereum/go-ethereum/p2p/discover"
+)
 
 // Protocol represents a P2P subprotocol implementation.
 type Protocol struct {
@@ -39,6 +43,15 @@ type Protocol struct {
 	// any protocol-level error (such as an I/O error) that is
 	// encountered.
 	Run func(peer *Peer, rw MsgReadWriter) error
+
+	// NodeInfo is an optional helper method to retrieve protocol specific metadata
+	// about the host node.
+	NodeInfo func() interface{}
+
+	// PeerInfo is an optional helper method to retrieve protocol specific metadata
+	// about a certain peer in the network. If an info retrieval function is set,
+	// but returns nil, it is assumed that the protocol handshake is still running.
+	PeerInfo func(id discover.NodeID) interface{}
 }
 
 func (p Protocol) cap() Cap {
diff --git a/p2p/server.go b/p2p/server.go
index 6060adc71..ee670b10e 100644
--- a/p2p/server.go
+++ b/p2p/server.go
@@ -689,3 +689,66 @@ func (srv *Server) runPeer(p *Peer) {
 		NumConnections: srv.PeerCount(),
 	})
 }
+
+// NodeInfo represents a short summary of the information known about the host.
+type NodeInfo struct {
+	ID    string `json:"id"`    // Unique node identifier (also the encryption key)
+	Name  string `json:"name"`  // Name of the node, including client type, version, OS, custom data
+	Enode string `json:"enode"` // Enode URL for adding this peer from remote peers
+	IP    string `json:"ip"`    // IP address of the node
+	Ports struct {
+		Discovery int `json:"discovery"` // UDP listening port for discovery protocol
+		Listener  int `json:"listener"`  // TCP listening port for RLPx
+	} `json:"ports"`
+	ListenAddr string                 `json:"listenAddr"`
+	Protocols  map[string]interface{} `json:"protocols"`
+}
+
+// Info gathers and returns a collection of metadata known about the host.
+func (srv *Server) NodeInfo() *NodeInfo {
+	node := srv.Self()
+
+	// Gather and assemble the generic node infos
+	info := &NodeInfo{
+		Name:       srv.Name,
+		Enode:      node.String(),
+		ID:         node.ID.String(),
+		IP:         node.IP.String(),
+		ListenAddr: srv.ListenAddr,
+		Protocols:  make(map[string]interface{}),
+	}
+	info.Ports.Discovery = int(node.UDP)
+	info.Ports.Listener = int(node.TCP)
+
+	// Gather all the running protocol infos (only once per protocol type)
+	for _, proto := range srv.Protocols {
+		if _, ok := info.Protocols[proto.Name]; !ok {
+			nodeInfo := interface{}("unknown")
+			if query := proto.NodeInfo; query != nil {
+				nodeInfo = proto.NodeInfo()
+			}
+			info.Protocols[proto.Name] = nodeInfo
+		}
+	}
+	return info
+}
+
+// PeersInfo returns an array of metadata objects describing connected peers.
+func (srv *Server) PeersInfo() []*PeerInfo {
+	// Gather all the generic and sub-protocol specific infos
+	infos := make([]*PeerInfo, 0, srv.PeerCount())
+	for _, peer := range srv.Peers() {
+		if peer != nil {
+			infos = append(infos, peer.Info())
+		}
+	}
+	// Sort the result array alphabetically by node identifier
+	for i := 0; i < len(infos); i++ {
+		for j := i + 1; j < len(infos); j++ {
+			if infos[i].ID > infos[j].ID {
+				infos[i], infos[j] = infos[j], infos[i]
+			}
+		}
+	}
+	return infos
+}
diff --git a/rpc/api/admin.go b/rpc/api/admin.go
index eb08fbc5d..b359d52a1 100644
--- a/rpc/api/admin.go
+++ b/rpc/api/admin.go
@@ -32,6 +32,7 @@ import (
 	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/eth"
 	"github.com/ethereum/go-ethereum/logger/glog"
+	"github.com/ethereum/go-ethereum/p2p"
 	"github.com/ethereum/go-ethereum/rlp"
 	"github.com/ethereum/go-ethereum/rpc/codec"
 	"github.com/ethereum/go-ethereum/rpc/comms"
@@ -80,15 +81,17 @@ type adminhandler func(*adminApi, *shared.Request) (interface{}, error)
 // admin api provider
 type adminApi struct {
 	xeth     *xeth.XEth
+	network  *p2p.Server
 	ethereum *eth.Ethereum
 	codec    codec.Codec
 	coder    codec.ApiCoder
 }
 
 // create a new admin api instance
-func NewAdminApi(xeth *xeth.XEth, ethereum *eth.Ethereum, codec codec.Codec) *adminApi {
+func NewAdminApi(xeth *xeth.XEth, network *p2p.Server, ethereum *eth.Ethereum, codec codec.Codec) *adminApi {
 	return &adminApi{
 		xeth:     xeth,
+		network:  network,
 		ethereum: ethereum,
 		codec:    codec,
 		coder:    codec.New(nil),
@@ -137,11 +140,11 @@ func (self *adminApi) AddPeer(req *shared.Request) (interface{}, error) {
 }
 
 func (self *adminApi) Peers(req *shared.Request) (interface{}, error) {
-	return self.ethereum.PeersInfo(), nil
+	return self.network.PeersInfo(), nil
 }
 
 func (self *adminApi) NodeInfo(req *shared.Request) (interface{}, error) {
-	return self.ethereum.NodeInfo(), nil
+	return self.network.NodeInfo(), nil
 }
 
 func (self *adminApi) DataDir(req *shared.Request) (interface{}, error) {
diff --git a/rpc/api/utils.go b/rpc/api/utils.go
index 5a3ade46b..6dde4022b 100644
--- a/rpc/api/utils.go
+++ b/rpc/api/utils.go
@@ -165,7 +165,7 @@ func ParseApiString(apistr string, codec codec.Codec, xeth *xeth.XEth, eth *eth.
 	for i, name := range names {
 		switch strings.ToLower(strings.TrimSpace(name)) {
 		case shared.AdminApiName:
-			apis[i] = NewAdminApi(xeth, eth, codec)
+			apis[i] = NewAdminApi(xeth, eth.Network(), eth, codec)
 		case shared.DebugApiName:
 			apis[i] = NewDebugApi(xeth, eth, codec)
 		case shared.DbApiName: