gonews/networker/connection.go

95 lines
2.6 KiB
Go

package networker
import (
// stdlib
"bufio"
"log"
"net"
"strings"
// local
"develop.pztrn.name/gonews/gonews/eventer"
)
// This function is a connection worker.
func connectionWorker(conn net.Conn) {
remoteAddr := conn.RemoteAddr()
log.Printf("accepted connection from %v\n", conn.RemoteAddr())
defer func() {
err := conn.Close()
if err != nil {
log.Println("Failed to close connection from " + remoteAddr.String() + ": " + err.Error())
}
log.Println("Connection from " + remoteAddr.String() + " closed")
}()
// Create buffers.
r := bufio.NewReader(conn)
w := bufio.NewWriter(conn)
scanr := bufio.NewScanner(r)
// Send greeting.
greetingData, _ := eventer.LaunchEvent("internal/greeting", nil)
greetingReply := greetingData.(*Reply)
_, err := w.WriteString(greetingReply.Code + " " + greetingReply.Data)
if err != nil {
log.Println("Failed to write greeting for " + remoteAddr.String() + ": " + err.Error())
return
}
w.Flush()
// Start reading for commands.
// Every command can be represented as slice where first element
// is actual command and all next - parameters.
// By default we read only one line per iteration.
// ToDo: multiline data parser for posting.
for {
dataAppeared := scanr.Scan()
if !dataAppeared {
log.Println("Failed to read data from " + remoteAddr.String() + ": " + scanr.Err().Error())
break
}
log.Println("Got data: " + scanr.Text())
// ToDo: what if we'll upload binary data here?
// Not supported yet.
data := strings.Split(scanr.Text(), " ")
replyRaw, err := eventer.LaunchEvent("commands/"+strings.ToLower(data[0]), data[1:])
if err != nil {
// We won't break here as this is just logging of appeared error.
log.Println("Error appeared while processing command '" + data[0] + "' for " + remoteAddr.String() + ": " + err.Error())
}
// We might have nil in reply, so we'll assume that passed command
// is unknown to us.
if replyRaw == nil {
_, err := w.WriteString(unknownCommandErrorCode + " " + unknownCommandErrorText + "\r\n")
if err != nil {
log.Println("Failed to write string to socket for " + remoteAddr.String() + ": " + err.Error())
break
}
w.Flush()
continue
}
// Every reply will be a reply struct.
reply := replyRaw.(*Reply)
_, err1 := w.WriteString(reply.Code + " " + reply.Data)
if err1 != nil {
log.Println("Failed to write string to socket for " + remoteAddr.String() + ": " + err1.Error())
break
}
w.Flush()
// Check for QUIT command.
if strings.ToLower(data[0]) == "quit" {
log.Println("QUIT command received, closing connection to " + remoteAddr.String())
break
}
}
}