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Documentation

Index

• type Config
• type ReadPacket
• type Table
  • func (tab *Table) ReadRandomNodes(buf []*enode.Node) (n int)
• type TalkRequestHandler
• type UDPConn
• type UDPv4
  • func ListenUDP(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)
  • func ListenV4(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)
  • func (t *UDPv4) Close()
  • func (t *UDPv4) LookupPubkey(key *ecdsa.PublicKey) []*enode.Node
  • func (t *UDPv4) Ping(n *enode.Node) error
  • func (t *UDPv4) RandomNodes() enode.Iterator
  • func (t *UDPv4) RequestENR(n *enode.Node) (*enode.Node, error)
  • func (t *UDPv4) Resolve(n *enode.Node) *enode.Node
  • func (t *UDPv4) Self() *enode.Node
• type UDPv5
  • func ListenV5(conn UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv5, error)
  • func (t *UDPv5) AllNodes() []*enode.Node
  • func (t *UDPv5) Close()
  • func (t *UDPv5) LocalNode() *enode.LocalNode
  • func (t *UDPv5) Lookup(target enode.ID) []*enode.Node
  • func (t *UDPv5) Ping(n *enode.Node) error
  • func (t *UDPv5) RandomNodes() enode.Iterator
  • func (t *UDPv5) RegisterTalkHandler(protocol string, handler TalkRequestHandler)
  • func (t *UDPv5) RequestENR(n *enode.Node) (*enode.Node, error)
  • func (t *UDPv5) Resolve(n *enode.Node) *enode.Node
  • func (t *UDPv5) Self() *enode.Node
  • func (t *UDPv5) TalkRequest(n *enode.Node, protocol string, request []byte) ([]byte, error)

Types

type Config

type Config struct {
	// These settings are required and configure the UDP listener:
	// 必选字段
	PrivateKey *ecdsa.PrivateKey

	// These settings are optional:
	// 可选字段
	NetRestrict *netutil.Netlist // list of allowed IP networks
	Bootnodes   []*enode.Node    // list of bootstrap nodes
	// 可选字段,所有没被处理的数据包发送到这里
	Unhandled chan<- ReadPacket // unhandled packets are sent on this channel
	// 默认是log.Root()
	Log log.Logger // if set, log messages go here
	// 默认是当前所有节点标识方案
	ValidSchemes enr.IdentityScheme // allowed identity schemes
	// 默认使用系统时钟
	Clock mclock.Clock
}

Config holds settings for the discovery listener. 启动节点发现监听服务使用的配置 必须设置的字段是PrivateKey

type ReadPacket

type ReadPacket struct {
	Data []byte
	Addr *net.UDPAddr
}

ReadPacket is a packet that couldn't be handled. Those packets are sent to the unhandled channel if configured. 用于表示不能被处理的数据包,他们被发送到unhandled管道

type Table

type Table struct {
	// contains filtered or unexported fields
}

Table is the 'node table', a Kademlia-like index of neighbor nodes. The table keeps itself up-to-date by verifying the liveness of neighbors and requesting their node records when announcements of a new record version are received.

func (*Table) ReadRandomNodes

func (tab *Table) ReadRandomNodes(buf []*enode.Node) (n int)

ReadRandomNodes fills the given slice with random nodes from the table. The results are guaranteed to be unique for a single invocation, no node will appear twice. 选取随机的节点到buf中,选取的个数是buf的长度 返回填充的节点个数

type TalkRequestHandler

type TalkRequestHandler func(enode.ID, *net.UDPAddr, []byte) []byte

TalkRequestHandler callback processes a talk request and optionally returns a reply

type UDPConn

type UDPConn interface {
	ReadFromUDP(b []byte) (n int, addr *net.UDPAddr, err error)
	WriteToUDP(b []byte, addr *net.UDPAddr) (n int, err error)
	Close() error
	LocalAddr() net.Addr
}

UDPConn is a network connection on which discovery can operate. UDPConn接口是节点发现过程中使用的网络连接 可以使用别的对象实现该接口就可以替换节点发现过程使用的通信链路

type UDPv4

type UDPv4 struct {
	// contains filtered or unexported fields
}

UDPv4 implements the v4 wire protocol.

func ListenUDP

func ListenUDP(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)

ListenUDP starts listening for discovery packets on the given UDP socket. ListenUDP在UDP端口上启动监听节点发现的数据包 有ListenV4和ListenV5两个参数完全一致的函数,现在ListenUDP还默认使用ListenV4实现

func ListenV4

func ListenV4(c UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv4, error)

启动v4版本的节点发现 启动后开始监听远程节点发送的数据包并进行处理

func (*UDPv4) Close

func (t *UDPv4) Close()

Close shuts down the socket and aborts any running queries.

func (*UDPv4) LookupPubkey

func (t *UDPv4) LookupPubkey(key *ecdsa.PublicKey) []*enode.Node

LookupPubkey finds the closest nodes to the given public key. 根据节点的公钥查询距离最近的节点

func (*UDPv4) Ping

func (t *UDPv4) Ping(n *enode.Node) error

Ping sends a ping message to the given node.

func (*UDPv4) RandomNodes

func (t *UDPv4) RandomNodes() enode.Iterator

RandomNodes is an iterator yielding nodes from a random walk of the DHT.

func (*UDPv4) RequestENR

func (t *UDPv4) RequestENR(n *enode.Node) (*enode.Node, error)

RequestENR sends enrRequest to the given node and waits for a response. 向远程节点请求最新的ENR记录 RequestENR的结构 packet = packet-header || packet-data packet-header = hash || signature || packet-type hash = keccak256(signature || packet-type || packet-data) signature = sign(packet-type || packet-data) packet-data = [expiration]

func (*UDPv4) Resolve

func (t *UDPv4) Resolve(n *enode.Node) *enode.Node

Resolve searches for a specific node with the given ID and tries to get the most recent version of the node record for it. It returns n if the node could not be resolved. 获取输入节点的ENR记录的最新版本

func (*UDPv4) Self

func (t *UDPv4) Self() *enode.Node

Self returns the local node.

type UDPv5

type UDPv5 struct {
	// contains filtered or unexported fields
}

UDPv5 is the implementation of protocol version 5.

func ListenV5

func ListenV5(conn UDPConn, ln *enode.LocalNode, cfg Config) (*UDPv5, error)

ListenV5 listens on the given connection.

func (*UDPv5) AllNodes

func (t *UDPv5) AllNodes() []*enode.Node

AllNodes returns all the nodes stored in the local table.

func (*UDPv5) Close

func (t *UDPv5) Close()

Close shuts down packet processing.

func (*UDPv5) LocalNode

func (t *UDPv5) LocalNode() *enode.LocalNode

LocalNode returns the current local node running the protocol.

func (*UDPv5) Lookup

func (t *UDPv5) Lookup(target enode.ID) []*enode.Node

Lookup performs a recursive lookup for the given target. It returns the closest nodes to target.

func (*UDPv5) Ping

func (t *UDPv5) Ping(n *enode.Node) error

Ping sends a ping message to the given node.

func (*UDPv5) RandomNodes

func (t *UDPv5) RandomNodes() enode.Iterator

RandomNodes returns an iterator that finds random nodes in the DHT.

func (*UDPv5) RegisterTalkHandler

func (t *UDPv5) RegisterTalkHandler(protocol string, handler TalkRequestHandler)

RegisterTalkHandler adds a handler for 'talk requests'. The handler function is called whenever a request for the given protocol is received and should return the response data or nil.

func (*UDPv5) RequestENR

func (t *UDPv5) RequestENR(n *enode.Node) (*enode.Node, error)

requestENR requests n's record.

func (*UDPv5) Resolve

func (t *UDPv5) Resolve(n *enode.Node) *enode.Node

Resolve searches for a specific node with the given ID and tries to get the most recent version of the node record for it. It returns n if the node could not be resolved.

func (*UDPv5) Self

func (t *UDPv5) Self() *enode.Node

Self returns the local node record.

func (*UDPv5) TalkRequest

func (t *UDPv5) TalkRequest(n *enode.Node, protocol string, request []byte) ([]byte, error)

TalkRequest sends a talk request to n and waits for a response.