Merge pull request #132 from leanix/feature/CID-3977/fix-concurrency-issue-when-sending-a-message

CID-3977: Fix concurrency issue by synchronizing server message sends

Author: mohamedlajmileanix

src/main/kotlin/net/leanix/githubagent/exceptions/Exceptions.kt

@@ -14,4 +14,8 @@ class GraphQLApiException(errors: List<GraphQLClientError>) :
 class WebhookSecretNotSetException : RuntimeException("Webhook secret not set")
 class InvalidEventSignatureException : RuntimeException("Invalid event signature")
 class ManifestFileNotFoundException : RuntimeException("Manifest File Not Found")
-class UnableToSendMessageException : RuntimeException("Unable to send message to the backend")
+class UnableToSendMessageException(exception: Exception) :
+    RuntimeException(
+        "Unable to send message to the backend",
+        exception
+    )

src/main/kotlin/net/leanix/githubagent/services/WebSocketService.kt

@@ -8,6 +8,7 @@ import net.leanix.githubagent.shared.TOPIC_PREFIX
 import org.slf4j.LoggerFactory
 import org.springframework.messaging.simp.stomp.StompSession
 import org.springframework.stereotype.Service
+import java.util.concurrent.locks.ReentrantLock
 
 @Service
 class WebSocketService(
@@ -18,6 +19,7 @@ class WebSocketService(
 
     private val logger = LoggerFactory.getLogger(WebSocketService::class.java)
     var stompSession: StompSession? = null
+    private val stompSendLock = ReentrantLock()
 
     fun initSession() {
         logger.info("Initializing websocket session")
@@ -35,10 +37,13 @@ class WebSocketService(
         if (!brokerStompSessionHandler.isConnected() && cachingService.get("runId") == null) {
             return
         }
-        runCatching {
+        stompSendLock.lock()
+        try {
             stompSession!!.send("$TOPIC_PREFIX$topic", data)
-        }.onFailure {
-            throw UnableToSendMessageException()
+        } catch (e: Exception) {
+            throw UnableToSendMessageException(e)
+        } finally {
+            stompSendLock.unlock()
         }
     }
 }