package tcp_server
import (
"bufio"
"log"
"net"
)
// Client holds info about connection
type Client struct {
conn net.Conn
Server *server
}
// TCP server
type server struct {
address string // Address to open connection: localhost:9999
onNewClientCallback func(c *Client)
onClientConnectionClosed func(c *Client, err error)
onNewMessage func(c *Client, message string)
}
// Read client data from channel
func (c *Client) listen() {
reader := bufio.NewReader(c.conn)
for {
message, err := reader.ReadString('\n')
if err != nil {
c.conn.Close()
c.Server.onClientConnectionClosed(c, err)
return
}
c.Server.onNewMessage(c, message)
}
}
// Send text message to client
func (c *Client) Send(message string) error {
_, err := c.conn.Write([]byte(message))
return err
}
// Send bytes to client
func (c *Client) SendBytes(b []byte) error {
_, err := c.conn.Write(b)
return err
}
func (c *Client) Conn() net.Conn {
return c.conn
}
func (c *Client) Close() error {
return c.conn.Close()
}
// Called right after server starts listening new client
func (s *server) OnNewClient(callback func(c *Client)) {
s.onNewClientCallback = callback
}
// Called right after connection closed
func (s *server) OnClientConnectionClosed(callback func(c *Client, err error)) {
s.onClientConnectionClosed = callback
}
// Called when Client receives new message
func (s *server) OnNewMessage(callback func(c *Client, message string)) {
s.onNewMessage = callback
}
// Start network server
func (s *server) Listen() {
listener, err := net.Listen("tcp", s.address)
if err != nil {
log.Fatal("Error starting TCP server.")
}
defer listener.Close()
for {
conn, _ := listener.Accept()
client := &Client{
conn: conn,
Server: s,
}
go client.listen()
s.onNewClientCallback(client)
}
}
// Creates new tcp server instance
func New(address string) *server {
log.Println("Creating server with address", address)
server := &server{
address: address,
}
server.OnNewClient(func(c *Client) {})
server.OnNewMessage(func(c *Client, message string) {})
server.OnClientConnectionClosed(func(c *Client, err error) {})
return server
}
