Add history parameter to restore old chats

cmd/server.go

@@ -37,6 +37,7 @@ func init() {
 	// and all subcommands, e.g.:
 	// serverCmd.PersistentFlags().String("foo", "", "A help for foo")
 	serverCmd.PersistentFlags().String("port", "1302", "port to use for listening")
+	serverCmd.PersistentFlags().String("history", "", "File to store and recover chat history from")
 
 	// Cobra supports local flags which will only run when this command
 	// is called directly, e.g.:
@@ -51,5 +52,13 @@ func setServerParameters(cmd *cobra.Command) error {
 	if parameterPort != "" {
 		listenPort = parameterPort
 	}
+	parameterHistory, err := cmd.Flags().GetString("history")
+	if err != nil {
+		return err
+	}
+	if parameterHistory != "" {
+		logLocation = parameterHistory
+		isLogging = true
+	}
 	return nil
 }

cmd/serverFunc.go

@@ -9,17 +9,17 @@ import (
 	"fmt"
 	"log"
 	"net"
+	"os"
 	"strings"
 )
 
 var (
-	listenPort string = "1302"
+	listenPort   string = "1302"
+	isLogging    bool   = false
+	logLocation  string
+	listenerList []chan string
 )
 
-type Creator interface {
-	CreateUser()
-}
-
 type User struct {
 	Username string
 	IP       string
@@ -49,8 +49,6 @@ func Server() {
 	}
 }
 
-var listenerList []chan string
-
 func getUsername(conn net.Conn) (s string, err error) {
 	conn.Write([]byte("What's your name?\nChoice: "))
 	name, err := bufio.NewReader(conn).ReadString('\n')
@@ -78,6 +76,22 @@ func removeFromList(chatChan chan string) {
 	}
 }
 
+func populateChat(conn net.Conn) {
+	if isLogging == false {
+		return
+	}
+	file, err := os.Open(logLocation)
+	if err != nil {
+		log.Printf("Error opening file for populating: %v\n", err)
+	}
+	defer file.Close()
+	scanner := bufio.NewScanner(file)
+	for scanner.Scan() {
+		conn.Write([]byte(fmt.Sprintln(scanner.Text())))
+	}
+
+}
+
 func handleConn(conn net.Conn, chatChan chan string) {
 	defer conn.Close()
 
@@ -94,11 +108,13 @@ func handleConn(conn net.Conn, chatChan chan string) {
 	}
 	userIP := getIP(conn)
 	//////////////////////////////////
+	populateChat(conn)
 
 	newUserTemplate := new(User)
 	newUser := newUserTemplate.CreateUser(userName, userIP)
 	joinMessage := fmt.Sprintf("%v has joined the chat!", newUser.Username)
 	fmt.Println(joinMessage)
+	addToLog(fmt.Sprintln(joinMessage))
 	//conn.Write([]byte(joinMessage))
 	sendMessage(joinMessage)
 
@@ -108,6 +124,7 @@ func handleConn(conn net.Conn, chatChan chan string) {
 		if err != nil {
 			quitMessage := fmt.Sprintf("%v has disconnected!", newUser.Username)
 			fmt.Println(quitMessage)
+			addToLog(fmt.Sprintln(quitMessage))
 			sendMessage(quitMessage)
 			//removeFromList(chatChan)
 			// if _, err := conn.Write([]byte(quitMessage)); err != nil {
@@ -116,7 +133,9 @@ func handleConn(conn net.Conn, chatChan chan string) {
 			return
 		}
 		finalMessage := fmt.Sprintf("[%v] %v: %v", newUser.IP, newUser.Username, strings.TrimRight(message, "\n"))
-		fmt.Printf("%v\n", finalMessage)
+		fm := fmt.Sprintf("%v\n", finalMessage)
+		fmt.Print(fm)
+		addToLog(fm)
 		sendMessage(finalMessage)
 
 		//chatChan <- finalMessage
@@ -148,3 +167,15 @@ func getIP(conn net.Conn) (IP string) {
 	}
 	return IP
 }
+
+func addToLog(s string) {
+	if isLogging == false {
+		return
+	}
+	file, err := os.OpenFile(logLocation, os.O_APPEND|os.O_WRONLY|os.O_CREATE, 0640)
+	if err != nil {
+		log.Printf("Error occurred: %v\n", err)
+	}
+	defer file.Close()
+	file.WriteString(s)
+}