I have a server that listens to 2 ports and transfers messages between the 2 ports. The only problem is that each client (or each port) has to submit a message before they can receive the previous message that the other port sent. For example, if client 1 says "hello", client 2 will not receive the message unless he sends a message first.
I want to find a way to make it so that each client will have to receive the previous message before being able to send a new one. (Since Client 1 will not have anything to receive until Client 2 says something, I am planning to send it a string that has placeholder text.)
Can anyone help me with how to go about this? I try putting my listening code and my code for writing a message for each client into their own go routines, but that did not do the job. Any help will be appreciated.
Here is my code:
Server
package main
import (
"fmt"
"log"
"net"
)
var message string = "Client 2 is receiving your message"
func main() {
fmt.Println("The server is listening on Port 3000 and 8080")
//Set up listeners for the ports each client is using
listener, err := net.Listen("tcp", "localhost:3000")
if err != nil {
log.Fatal(err)
}
listener2, err := net.Listen("tcp", "localhost:8080")
if err != nil {
log.Fatal(err)
}
go acceptLoop(listener)
acceptLoop(listener2) // run in the main goroutine
}
func acceptLoop(l net.Listener) {
defer l.Close()
for {
c, err := l.Accept()
if err != nil {
log.Fatal(err)
}
fmt.Println("New connection found!")
go listenConnection(c)
}
}
func listenConnection(conn net.Conn) {
fmt.Println("Yay")
for {
buffer := make([]byte, 1400)
dataSize, err := conn.Read(buffer)
if err != nil {
fmt.Println("Connection has closed")
return
}
//This is the message you received
data := buffer[:dataSize]
fmt.Print("Received message: ", string(data))
// Send the message back
_, err = conn.Write([]byte(message))
if err != nil {
log.Fatalln(err)
}
fmt.Print("Message sent: ", string(data))
message = string(data)
}
}
Client 1
package main
import (
"fmt"
"log"
"net"
"bufio"
"os"
)
func main() {
conn, err := net.Dial("tcp", "localhost:3000")
if err != nil {
log.Fatalln(err)
}
for {
reader := bufio.NewReader(os.Stdin)
fmt.Print("Enter text: ")
text, _ := reader.ReadString('
')
_, err = conn.Write([]byte(text))
if err != nil {
log.Fatalln(err)
}
for {
buffer := make([]byte, 1400)
dataSize, err := conn.Read(buffer)
if err != nil {
fmt.Println("The connection has closed!")
return
}
data := buffer[:dataSize]
fmt.Println("Received message: ", string(data))
break
}
}
}
My second client is the same as my first except "localhost:3000" is replaced with "localhost:8080".
I will appreciate any help! I'm fairly new to networking and Go, so any tips will be great.