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

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
+}