a simple chat engine of golang

conn_hub.go

package chatengine

import (
	"fmt"
	"net"
)

type ConnHub struct {
	cap  int
	pool map[net.Addr]net.Conn
	ops  chan func(map[net.Addr]net.Conn)
}

func NewConnHub(cap int) *ConnHub {
	return &ConnHub{
		cap:  cap,
		pool: make(map[net.Addr]net.Conn, cap),
		ops:  make(chan func(map[net.Addr]net.Conn)),
	}
}

func (v *ConnHub) Join(conn net.Conn) {
	v.ops <- func(m map[net.Addr]net.Conn) {
		m[conn.RemoteAddr()] = conn
	}
}

func (v *ConnHub) Leave(addr net.Addr) {
	v.ops <- func(m map[net.Addr]net.Conn) {
		delete(m, addr)
	}
}

func (v *ConnHub) SendMsgPublic(msg []byte) error {
	results := make(chan error, 1)
	v.ops <- func(m map[net.Addr]net.Conn) {
		for _, c := range m {
			_, err := c.Write(msg)
			if err != nil {
				results <- err
				return
			}
		}
		results <- nil
	}
	return <-results
}

func (v *ConnHub) SendMsgPrivate(addr net.Addr, msg []byte) error {
	results := make(chan net.Conn, 1)
	v.ops <- func(m map[net.Addr]net.Conn) {
		results <- m[addr]
	}
	conn := <-results
	if conn == nil {
		return fmt.Errorf("client of %s is not registered", addr)
	}
	_, err := conn.Write(msg)
	return err
}

func (v *ConnHub) Loop() {
	for op := range v.ops {
		op(v.pool)
	}
}