Documentation ¶
Overview ¶
Package p2p implements the Ethereum p2p network protocols.
Index ¶
- Constants
- Variables
- func ExpectMsg(r MsgReader, code uint64, content interface{}) error
- func MsgPipe() (*MsgPipeRW, *MsgPipeRW)
- func Send(w MsgWriter, msgcode uint64, data interface{}) error
- func SendItems(w MsgWriter, msgcode uint64, elems ...interface{}) error
- type Cap
- type Config
- type DiscReason
- type Msg
- type MsgPipeRW
- type MsgReadWriter
- type MsgReader
- type MsgWriter
- type NodeInfo
- type Peer
- type PeerInfo
- type Protocol
- type Server
- func (srv *Server) AddPeer(node *discover.Node)
- func (srv *Server) NodeInfo() *NodeInfo
- func (srv *Server) PeerCount() int
- func (srv *Server) Peers() []*Peer
- func (srv *Server) PeersInfo() []*PeerInfo
- func (srv *Server) RemovePeer(node *discover.Node)
- func (srv *Server) Self() *discover.Node
- func (srv *Server) Start() (err error)
- func (srv *Server) Stop()
Examples ¶
Constants ¶
const ( NODE_NAME_LENGTH = 32 PERMISSIONED_CONFIG = "permissioned-nodes.json" )
Variables ¶
var ErrPipeClosed = errors.New("p2p: read or write on closed message pipe")
ErrPipeClosed is returned from pipe operations after the pipe has been closed.
Functions ¶
func ExpectMsg ¶
ExpectMsg reads a message from r and verifies that its code and encoded RLP content match the provided values. If content is nil, the payload is discarded and not verified.
func MsgPipe ¶
MsgPipe creates a message pipe. Reads on one end are matched with writes on the other. The pipe is full-duplex, both ends implement MsgReadWriter.
Example ¶
rw1, rw2 := MsgPipe() go func() { Send(rw1, 8, [][]byte{{0, 0}}) Send(rw1, 5, [][]byte{{1, 1}}) rw1.Close() }() for { msg, err := rw2.ReadMsg() if err != nil { break } var data [][]byte msg.Decode(&data) fmt.Printf("msg: %d, %x\n", msg.Code, data[0]) }
Output: msg: 8, 0000 msg: 5, 0101
Types ¶
type Config ¶
type Config struct { // This field must be set to a valid secp256k1 private key. PrivateKey *ecdsa.PrivateKey // MaxPeers is the maximum number of peers that can be // connected. It must be greater than zero. 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 // Discovery specifies whether the peer discovery mechanism should be started // or not. Disabling is usually useful for protocol debugging (manual topology). Discovery bool // Name sets the node name of this server. // Use common.MakeName to create a name that follows existing conventions. Name string // Bootstrap nodes are used to establish connectivity // with the rest of the network. BootstrapNodes []*discover.Node // Static nodes are used as pre-configured connections which are always // maintained and re-connected on disconnects. StaticNodes []*discover.Node // Trusted nodes are used as pre-configured connections which are always // allowed to connect, even above the peer limit. TrustedNodes []*discover.Node // NodeDatabase is the path to the database containing the previously seen // live nodes in the network. NodeDatabase string // Protocols should contain the protocols supported // by the server. Matching protocols are launched for // each peer. Protocols []Protocol // If ListenAddr is set to a non-nil address, the server // will listen for incoming connections. // // If the port is zero, the operating system will pick a port. The // ListenAddr field will be updated with the actual address when // the server is started. 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 server will not dial any peers. NoDial bool //Enables Permissioning EnableNodePermission bool //DataDir DataDir string }
Config holds Server options.
type DiscReason ¶
type DiscReason uint
const ( DiscRequested DiscReason = iota DiscNetworkError DiscProtocolError DiscUselessPeer DiscTooManyPeers DiscAlreadyConnected DiscIncompatibleVersion DiscInvalidIdentity DiscQuitting DiscUnexpectedIdentity DiscSelf DiscReadTimeout DiscSubprotocolError = 0x10 )
func (DiscReason) Error ¶
func (d DiscReason) Error() string
func (DiscReason) String ¶
func (d DiscReason) String() string
type Msg ¶
type Msg struct { Code uint64 Size uint32 // size of the paylod Payload io.Reader ReceivedAt time.Time }
Msg defines the structure of a p2p message.
Note that a Msg can only be sent once since the Payload reader is consumed during sending. It is not possible to create a Msg and send it any number of times. If you want to reuse an encoded structure, encode the payload into a byte array and create a separate Msg with a bytes.Reader as Payload for each send.
func (Msg) Decode ¶
Decode parses the RLP content of a message into the given value, which must be a pointer.
For the decoding rules, please see package rlp.
type MsgPipeRW ¶
type MsgPipeRW struct {
// contains filtered or unexported fields
}
MsgPipeRW is an endpoint of a MsgReadWriter pipe.
func (*MsgPipeRW) Close ¶
Close unblocks any pending ReadMsg and WriteMsg calls on both ends of the pipe. They will return ErrPipeClosed. Close also interrupts any reads from a message payload.
type MsgReadWriter ¶
MsgReadWriter provides reading and writing of encoded messages. Implementations should ensure that ReadMsg and WriteMsg can be called simultaneously from multiple goroutines.
type NodeInfo ¶
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"` }
NodeInfo represents a short summary of the information known about the host.
type Peer ¶
type Peer struct {
// contains filtered or unexported fields
}
Peer represents a connected remote node.
func (*Peer) Disconnect ¶
func (p *Peer) Disconnect(reason DiscReason)
Disconnect terminates the peer connection with the given reason. It returns immediately and does not wait until the connection is closed.
func (*Peer) RemoteAddr ¶
RemoteAddr returns the remote address of the network connection.
type PeerInfo ¶
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 }
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 Protocol ¶
type Protocol struct { // Name should contain the official protocol name, // often a three-letter word. Name string // Version should contain the version number of the protocol. Version uint // Length should contain the number of message codes used // by the protocol. Length uint64 // Run is called in a new groutine when the protocol has been // negotiated with a peer. It should read and write messages from // rw. The Payload for each message must be fully consumed. // // The peer connection is closed when Start returns. It should return // 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{} }
Protocol represents a P2P subprotocol implementation.
type Server ¶
type Server struct { // Config fields may not be modified while the server is running. Config // contains filtered or unexported fields }
Server manages all peer connections.
func (*Server) AddPeer ¶
AddPeer connects to the given node and maintains the connection until the server is shut down. If the connection fails for any reason, the server will attempt to reconnect the peer.
func (*Server) PeersInfo ¶
PeersInfo returns an array of metadata objects describing connected peers.
func (*Server) RemovePeer ¶
RemovePeer disconnects from the given node