caching the last X log messages

dist/script.js

@@ -86,14 +86,9 @@ function addMessage(messageType, serviceType, serviceName, message, timestamp) {
     deleteOldMessages()
 }
 
-function addViewerInfoMessage(joined, timestamp) {
+function addCustomMessage(message) {
     let li = document.createElement("li")
-
-    if (joined) {
-        li.innerHTML = formatDate(timestamp) + "<span style='color: #2ecc71'>A client has joined</span>"
-    } else {
-        li.innerHTML = formatDate(timestamp) + "<span style='color: #e74c3c'>A client has left</span>"
-    }
+    li.innerHTML = message
 
     messages.appendChild(li)
 
@@ -104,6 +99,14 @@ function addViewerInfoMessage(joined, timestamp) {
     deleteOldMessages()
 }
 
+function addViewerInfoMessage(joined, timestamp) {
+    if (joined) {
+        addCustomMessage(formatDate(timestamp) + "<span style='color: #2ecc71'>A client has joined</span>")
+    } else {
+        addCustomMessage(formatDate(timestamp) + "<span style='color: #e74c3c'>A client has left</span>")
+    }
+}
+
 function deleteOldMessages() {
     if (messages.childElementCount > 500) {
         messages.removeChild(messages.getElementsByTagName("li")[0])
@@ -195,18 +198,28 @@ function connectWS() {
         serviceType = data.ServiceType
         timestamp = data.Timestamp
 
-        console.log(timestamp)
-
-        if (messageType == 100 && serviceName == 100) {
+        if (messageType == 100 && serviceName == 100) { // viewer count
             viewersCount.innerHTML = data.Msg + (data.Msg == 1 ? " viewer" : " viewers")
 
             addViewerInfoMessage(serviceType == 1, timestamp)
+        } else if (messageType == 101 && serviceName == 101 && serviceType == 101) {
+            lastMessages = JSON.parse(data.Msg)
+            
+            if (lastMessages != null && lastMessages.length > 0) {
+                addCustomMessage("<span style='color: #7f8c8d'>––––––––– START OF OLD MESSAGES –––––––––</span>")
+
+                for (const i in lastMessages) {
+                    addMessage(lastMessages[i].MessageType, lastMessages[i].ServiceType, lastMessages[i].ServiceName, lastMessages[i].Msg, lastMessages[i].Timestamp)
+                }
+
+                addCustomMessage("<span style='color: #7f8c8d'>––––––––– END OF OLD MESSAGES –––––––––</span>")
+            }
         } else {
             if (serviceType == 0 && !checkboxAlpha.checked) return
             if (serviceType == 1 && !checkboxBeta.checked) return
             if (serviceType == 2 && !checkboxStable.checked) return
 
-            addMessage(messageType, serviceType, serviceName, data["Msg"], timestamp)
+            addMessage(messageType, serviceType, serviceName, data.Msg, timestamp)
         }
     }
     

main.go

@@ -18,8 +18,6 @@
 package main
 
 import (
-	"time"
-
 	"clickandjoin.app/managementsystem/modules/config"
 	"clickandjoin.app/managementsystem/modules/rabbitmq"
 	"clickandjoin.app/managementsystem/modules/scylladb"
@@ -79,7 +77,5 @@ func main() {
 
 	router.SetupRoutes(app)
 
-	gocnjhelper.LogInfof("%s", time.Now().UnixMilli())
-
 	app.Listen(cfg.Host + ":" + cfg.Port)
 }

modules/cache/cache.go

@@ -4,35 +4,59 @@ import (
 	"sync"
 
 	"clickandjoin.app/managementsystem/modules/structs"
+	"clickandjoin.app/managementsystem/modules/utils"
+	gocnjhelper "git.clickandjoin.umbach.dev/ClickandJoin/go-cnj-helper"
 )
 
 var socketClients = make(map[string]*structs.SocketClient)
-var mu sync.RWMutex
+var muS sync.RWMutex
 
 func AddSocketClient(clientId string, socketClient *structs.SocketClient) {
-	mu.Lock()
+	muS.Lock()
 	socketClients[clientId] = socketClient
-	mu.Unlock()
+	muS.Unlock()
 }
 
 func DeleteClient(clientId string) {
-	mu.Lock()
+	muS.Lock()
 	delete(socketClients, clientId)
-	mu.Unlock()
+	muS.Unlock()
 }
 
 func GetSocketClients() map[string]*structs.SocketClient {
-	mu.RLock()
-	defer mu.RUnlock()
+	muS.RLock()
+	defer muS.RUnlock()
 
 	return socketClients
 }
 
 func GetSocketClient(clientId string) (socketClient *structs.SocketClient, ok bool) {
-	mu.RLock()
-	defer mu.RUnlock()
+	muS.RLock()
+	defer muS.RUnlock()
 
 	client, ok := socketClients[clientId]
 
 	return client, ok
 }
+
+var lastLogMessages []gocnjhelper.RabbitMqLogMessage
+var muL sync.RWMutex
+
+func AddLastLogMessage(rabbitMqLogMessage gocnjhelper.RabbitMqLogMessage) {
+	muL.Lock()
+
+	if len(lastLogMessages) > utils.CachedLastLogMessages {
+		lastLogMessages = lastLogMessages[1:]
+	}
+
+	lastLogMessages = append(lastLogMessages, rabbitMqLogMessage)
+
+	muL.Unlock()
+}
+
+func GetlastLogMessages() []gocnjhelper.RabbitMqLogMessage {
+	muL.RLock()
+	defer muL.RUnlock()
+
+	return lastLogMessages
+}

modules/rabbitmq/helper.go

@@ -3,10 +3,10 @@ package rabbitmq
 import (
 	"encoding/json"
 
+	"clickandjoin.app/managementsystem/modules/cache"
 	"clickandjoin.app/managementsystem/socketclients"
 	gocnjhelper "git.clickandjoin.umbach.dev/ClickandJoin/go-cnj-helper"
 	amqp "github.com/rabbitmq/amqp091-go"
-	"github.com/rs/zerolog/log"
 )
 
 func LogsMessagesHandling() {
@@ -50,10 +50,10 @@ func LogsMessagesHandling() {
 				continue
 			}
 
-			log.Info().Msgf("msg", logMessage)
-
 			socketclients.BroadcastLogMessage(logMessage)
 
+			cache.AddLastLogMessage(logMessage)
+
 			msg.Ack(false)
 		}
 	}

modules/utils/definitions.go

@@ -1 +1,3 @@
 package utils
+
+const CachedLastLogMessages = 499 // Number of messages held in the cache and sent to new clients to receive the latest messages

readme.md

@@ -1,4 +1,6 @@
-# Management System
+# Definitions that are specified in the app 
+
+[Click here to see the definitions](modules/utils/definitions.go)
 
 ## Tasks
 - Admin Dashboard

socketserver/hub.go

@@ -1,6 +1,9 @@
 package socketserver
 
 import (
+	"encoding/json"
+	"time"
+
 	"clickandjoin.app/managementsystem/modules/cache"
 	"clickandjoin.app/managementsystem/modules/structs"
 	"clickandjoin.app/managementsystem/socketclients"
@@ -24,6 +27,22 @@ func RunHub() {
 			cache.AddSocketClient(newSocketClient.ClientId, newSocketClient)
 
 			socketclients.BroadcastViewersCountMessage(1)
+			if socketClient, ok := cache.GetSocketClient(newSocketClient.ClientId); ok {
+				lastMessages, err := json.Marshal(cache.GetlastLogMessages())
+
+				if err != nil {
+					gocnjhelper.LogDebugf("Failed to marshal last messages, err: %s")
+					continue
+				}
+
+				socketClient.SendMessage(gocnjhelper.RabbitMqLogMessage{
+					MessageType: 101,
+					ServiceName: 101,
+					ServiceType: 101,
+					Msg:         string(lastMessages),
+					Timestamp:   time.Now().Unix(),
+				})
+			}
 
 		case data := <-broadcast:
 			gocnjhelper.LogDebugf("RECEIVED WEBSOCKET MESSAGE: %s", data.Msg)