feat: new features/improvements

- update dependencies
- add up/down time #14
- add workers with retry to help with spam

serverstatus/serverstatus.go

@@ -1,12 +1,14 @@
 package serverstatus
 
 import (
+	"fmt"
 	"log"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
-	"github.com/anvie/port-scanner"
+	portscanner "github.com/anvie/port-scanner"
 	"github.com/bwmarrin/discordgo"
 	steam "github.com/kidoman/go-steam"
 	"github.com/mgerb/ServerStatus/bot"
@@ -24,6 +26,8 @@ func Start() {
 	//set each server status as online to start
 	for i := range config.Config.Servers {
 		config.Config.Servers[i].Online = true
+		config.Config.Servers[i].OnlineTimestamp = time.Now()
+		config.Config.Servers[i].OfflineTimestamp = time.Now()
 	}
 
 	err := bot.Session.UpdateStatus(0, config.Config.GameStatus)
@@ -48,49 +52,74 @@ func scanServers() {
 
 	for {
 
-		for index, server := range config.Config.Servers {
-			prevServerUp := server.Online //set value to previous server status
+		// use waitgroup to scan all servers concurrently
+		var wg sync.WaitGroup
 
-			serverScanner := portscanner.NewPortScanner(server.Address, time.Second*2, 1)
-			serverUp := serverScanner.IsOpen(server.Port) //check if the port is open
-
-			// if server isn't up check RCON protocol (UDP)
-			if !serverUp {
-				host := server.Address + ":" + strconv.Itoa(server.Port)
-				steamConnection, err := steam.Connect(host)
-				if err == nil {
-					defer steamConnection.Close()
-					_, err := steamConnection.Ping()
-					if err == nil {
-						serverUp = true
-					}
-				}
-			}
-
-			if serverUp && serverUp != prevServerUp {
-				sendMessageToRooms(green, server.Name, "Is now online :smiley:", true)
-			} else if !serverUp && serverUp != prevServerUp {
-				sendMessageToRooms(red, server.Name, "Has gone offline :frowning2:", true)
-			}
-
-			config.Config.Servers[index].Online = serverUp
+		for index := range config.Config.Servers {
+			wg.Add(1)
+			go worker(index, &config.Config.Servers[index], &wg)
 		}
 
+		wg.Wait()
+
 		time.Sleep(time.Second * config.Config.PollingInterval)
 	}
 }
 
+func worker(index int, server *config.Server, wg *sync.WaitGroup) {
+	defer wg.Done()
+
+	prevServerUp := server.Online //set value to previous server status
+
+	var serverUp bool
+	retryCounter := 0
+
+	// try reconnecting 5 times if failure persists (every 2 seconds)
+	for {
+		serverScanner := portscanner.NewPortScanner(server.Address, time.Second*2, 1)
+		serverUp = serverScanner.IsOpen(server.Port) //check if the port is open
+		if serverUp || retryCounter >= 5 {
+			break
+		}
+		retryCounter++
+		time.Sleep(time.Second * 2)
+	}
+
+	// if server isn't up check RCON protocol (UDP)
+	if !serverUp {
+		host := server.Address + ":" + strconv.Itoa(server.Port)
+		steamConnection, err := steam.Connect(host)
+		if err == nil {
+			defer steamConnection.Close()
+			_, err := steamConnection.Ping()
+			if err == nil {
+				serverUp = true
+			}
+		}
+	}
+
+	if serverUp && serverUp != prevServerUp {
+		server.OnlineTimestamp = time.Now()
+		sendMessageToRooms(green, server.Name, "Is now online :smiley:", true)
+	} else if !serverUp && serverUp != prevServerUp {
+		server.OfflineTimestamp = time.Now()
+		sendMessageToRooms(red, server.Name, "Has gone offline :frowning2:", true)
+	}
+
+	server.Online = serverUp
+}
+
 func sendMessageToRooms(color int, title, description string, mentionRoles bool) {
 	for _, roomID := range config.Config.RoomIDList {
 		if mentionRoles {
 			content := strings.Join(config.Config.RolesToNotify, " ")
 			bot.Session.ChannelMessageSend(roomID, content)
 		}
-		sendEmbededMessage(roomID, color, title, description)
+		sendEmbeddedMessage(roomID, color, title, description)
 	}
 }
 
-func sendEmbededMessage(roomID string, color int, title, description string) {
+func sendEmbeddedMessage(roomID string, color int, title, description string) {
 
 	embed := &discordgo.MessageEmbed{
 		Color:       color,
@@ -110,13 +139,23 @@ func MessageHandler(s *discordgo.Session, m *discordgo.MessageCreate) {
 		return
 	}
 
-	if m.Content == "!ServerStatus" {
+	if m.Content == config.Config.BotPrefix+"ServerStatus" {
 		for _, server := range config.Config.Servers {
 			if server.Online {
-				sendEmbededMessage(m.ChannelID, green, server.Name, "Online!")
+				sendEmbeddedMessage(m.ChannelID, green, server.Name, "Online!\nUptime: "+fmtDuration(time.Since(server.OnlineTimestamp)))
 			} else {
-				sendEmbededMessage(m.ChannelID, red, server.Name, "Offline!")
+				sendEmbeddedMessage(m.ChannelID, red, server.Name, "Offline!\nDowntime: "+fmtDuration(time.Since(server.OfflineTimestamp)))
 			}
 		}
 	}
 }
+
+func fmtDuration(d time.Duration) string {
+
+	days := int(d.Hours()) / 24
+	hours := int(d.Hours()) % 60
+	minutes := int(d.Minutes()) % 60
+	seconds := int(d.Seconds()) % 60
+
+	return fmt.Sprintf("%dd %dh %dm %ds", days, hours, minutes, seconds)
+}