fix(jetbrains): avoid connection loops

Author: andreafalzetti

components/ide/jetbrains/gateway-plugin/src/main/kotlin/io/gitpod/jetbrains/gateway/GitpodConnectionProvider.kt

@@ -12,6 +12,7 @@ import com.intellij.ide.BrowserUtil
 import com.intellij.openapi.components.service
 import com.intellij.openapi.diagnostic.thisLogger
 import com.intellij.openapi.progress.ProgressManager
+import com.intellij.openapi.ui.Messages
 import com.intellij.remote.RemoteCredentialsHolder
 import com.intellij.ssh.AskAboutHostKey
 import com.intellij.ssh.OpenSshLikeHostKeyVerifier
@@ -31,6 +32,7 @@ import com.jetbrains.gateway.ssh.ClientOverSshTunnelConnector
 import com.jetbrains.gateway.ssh.SshHostTunnelConnector
 import com.jetbrains.gateway.thinClientLink.ThinClientHandle
 import com.jetbrains.rd.util.URI
+import com.jetbrains.rd.util.concurrentMapOf
 import com.jetbrains.rd.util.lifetime.Lifetime
 import io.gitpod.gitpodprotocol.api.entities.WorkspaceInstance
 import io.gitpod.jetbrains.icons.GitpodIcons
@@ -49,7 +51,7 @@ import kotlin.coroutines.coroutineContext
 
 @Suppress("UnstableApiUsage", "OPT_IN_USAGE")
 class GitpodConnectionProvider : GatewayConnectionProvider {
-
+    private val activeConnections = concurrentMapOf<String, Boolean>()
     private val gitpod = service<GitpodConnectionService>()
 
     private val httpClient = HttpClient.newBuilder()
@@ -59,6 +61,7 @@ class GitpodConnectionProvider : GatewayConnectionProvider {
     private val jacksonMapper = jacksonObjectMapper()
         .configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
 
+
     override suspend fun connect(
         parameters: Map<String, String>,
         requestor: ConnectionRequestor
@@ -74,6 +77,7 @@ class GitpodConnectionProvider : GatewayConnectionProvider {
             parameters["workspaceId"]!!,
             parameters["backendPort"]
         )
+
         val client = gitpod.obtainClient(connectParams.gitpodHost)
         val connectionLifetime = Lifetime.Eternal.createNested()
         val updates = client.listenToWorkspace(connectionLifetime, connectParams.workspaceId)
@@ -144,6 +148,22 @@ class GitpodConnectionProvider : GatewayConnectionProvider {
             connectionPanel.repaint()
         }
 
+        val connectionKeyId = "${connectParams.gitpodHost}-${connectParams.workspaceId}-${connectParams.backendPort}"
+
+        if (activeConnections.containsKey(connectionKeyId)) {
+            val message = "You are trying to connect to a workspace that has a session already open"
+            val title = "Oops"
+            val okButton = Messages.getOkButton()
+            val options = arrayOf(okButton)
+            val defaultIndex = 0
+            val icon = Messages.getWarningIcon()
+            Messages.showDialog(message, title, options, defaultIndex, icon)
+
+            val errMessage = "A connection to the same workspace already exists: $connectionKeyId"
+            thisLogger().warn(errMessage)
+            throw IllegalArgumentException(errMessage)
+        }
+
         GlobalScope.launch {
             var thinClient: ThinClientHandle? = null
             var thinClientJob: Job? = null
@@ -230,6 +250,12 @@ class GitpodConnectionProvider : GatewayConnectionProvider {
                                         setErrorMessage("failed to fetch JetBrains Gateway Join Link.")
                                         return@launch
                                     }
+
+                                    // TODO: is this the right place?
+                                    activeConnections[connectionKeyId] = true
+
+                                    thisLogger().warn("Storing connection for $connectionKeyId")
+
                                     val connector = ClientOverSshTunnelConnector(
                                         connectionLifetime,
                                         SshHostTunnelConnector(credentials),
@@ -239,6 +265,7 @@ class GitpodConnectionProvider : GatewayConnectionProvider {
                                     clientHandle.clientClosed.advise(connectionLifetime) {
                                         application.invokeLater {
                                             connectionLifetime.terminate()
+                                            activeConnections.remove(connectionKeyId)
                                         }
                                     }
                                     clientHandle.onClientPresenceChanged.advise(connectionLifetime) {