impl: notify user when agent can't be contacted (#249)

At a recent customer incident the Coder server could not ping the agent
for a short brief of time because of intermittent network issues. The
user had no idea they have network issues and was expecting the ssh
sessions to work flawlessly.

This PR lays the groundwork for monitoring the connection by checking
the status for workspace, agent and agent lifecycle and make an educated
guess when the network runs into issues.

- resolves #246

Author: fioan89

.gitignore

@@ -8,3 +8,4 @@ jvm/
 
 # hidden macOS metadata files
 .DS_Store
+bin/

src/main/kotlin/com/coder/toolbox/CoderRemoteEnvironment.kt

@@ -256,6 +256,9 @@ class CoderRemoteEnvironment(
         context.logger.info("Disconnected from $id")
     }
 
+    /**
+     * Update the workspace/agent status to the listeners, if it has changed.
+     */
     /**
      * Update the workspace/agent status to the listeners, if it has changed.
      */
@@ -265,15 +268,18 @@ class CoderRemoteEnvironment(
         }
         this.workspace = workspace
         this.agent = agent
+
         // workspace&agent status can be different from "environment status"
         // which is forced to queued state when a workspace is scheduled to start
         updateStatus(WorkspaceAndAgentStatus.from(workspace, agent))
+        context.connectionMonitoringService.checkConnectionStatus(workspace, agent)
 
         // we have to regenerate the action list in order to force a redraw
         // because the actions don't have a state flow on the enabled property
         refreshAvailableActions()
     }
 
+
     private fun updateStatus(status: WorkspaceAndAgentStatus) {
         environmentStatus = status
         state.update {

src/main/kotlin/com/coder/toolbox/CoderToolboxContext.kt

@@ -2,6 +2,7 @@ package com.coder.toolbox
 
 import com.coder.toolbox.store.CoderSecretsStore
 import com.coder.toolbox.store.CoderSettingsStore
+import com.coder.toolbox.util.ConnectionMonitoringService
 import com.coder.toolbox.util.toURL
 import com.jetbrains.toolbox.api.core.diagnostics.Logger
 import com.jetbrains.toolbox.api.core.os.LocalDesktopManager
@@ -30,6 +31,7 @@ data class CoderToolboxContext(
     val settingsStore: CoderSettingsStore,
     val secrets: CoderSecretsStore,
     val proxySettings: ToolboxProxySettings,
+    val connectionMonitoringService: ConnectionMonitoringService,
 ) {
     /**
      * Try to find a URL.

src/main/kotlin/com/coder/toolbox/CoderToolboxExtension.kt

@@ -3,6 +3,7 @@ package com.coder.toolbox
 import com.coder.toolbox.settings.Environment
 import com.coder.toolbox.store.CoderSecretsStore
 import com.coder.toolbox.store.CoderSettingsStore
+import com.coder.toolbox.util.ConnectionMonitoringService
 import com.jetbrains.toolbox.api.core.PluginSecretStore
 import com.jetbrains.toolbox.api.core.PluginSettingsStore
 import com.jetbrains.toolbox.api.core.ServiceLocator
@@ -26,21 +27,30 @@ import kotlinx.coroutines.CoroutineScope
 class CoderToolboxExtension : RemoteDevExtension {
     // All services must be passed in here and threaded as necessary.
     override fun createRemoteProviderPluginInstance(serviceLocator: ServiceLocator): RemoteProvider {
+        val ui = serviceLocator.getService<ToolboxUi>()
         val logger = serviceLocator.getService(Logger::class.java)
+        val cs = serviceLocator.getService<CoroutineScope>()
+        val i18n = serviceLocator.getService<LocalizableStringFactory>()
         return CoderRemoteProvider(
             CoderToolboxContext(
-                serviceLocator.getService<ToolboxUi>(),
+                ui,
                 serviceLocator.getService<EnvironmentUiPageManager>(),
                 serviceLocator.getService<EnvironmentStateColorPalette>(),
                 serviceLocator.getService<RemoteToolsHelper>(),
                 serviceLocator.getService<ClientHelper>(),
                 serviceLocator.getService<LocalDesktopManager>(),
-                serviceLocator.getService<CoroutineScope>(),
+                cs,
                 serviceLocator.getService<Logger>(),
-                serviceLocator.getService<LocalizableStringFactory>(),
+                i18n,
                 CoderSettingsStore(serviceLocator.getService<PluginSettingsStore>(), Environment(), logger),
                 CoderSecretsStore(serviceLocator.getService<PluginSecretStore>()),
-                serviceLocator.getService<ToolboxProxySettings>()
+                serviceLocator.getService<ToolboxProxySettings>(),
+                ConnectionMonitoringService(
+                    cs,
+                    ui,
+                    logger,
+                    i18n
+                )
             )
         )
     }

src/main/kotlin/com/coder/toolbox/util/ConnectionMonitoringService.kt

@@ -0,0 +1,58 @@
+package com.coder.toolbox.util
+
+import com.coder.toolbox.sdk.v2.models.Workspace
+import com.coder.toolbox.sdk.v2.models.WorkspaceAgent
+import com.coder.toolbox.sdk.v2.models.WorkspaceAgentLifecycleState
+import com.coder.toolbox.sdk.v2.models.WorkspaceAgentStatus
+import com.coder.toolbox.sdk.v2.models.WorkspaceStatus
+import com.jetbrains.toolbox.api.core.diagnostics.Logger
+import com.jetbrains.toolbox.api.localization.LocalizableStringFactory
+import com.jetbrains.toolbox.api.ui.ToolboxUi
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.launch
+import java.util.UUID
+
+class ConnectionMonitoringService(
+    private val cs: CoroutineScope,
+    private val ui: ToolboxUi,
+    private val logger: Logger,
+    private val i18n: LocalizableStringFactory
+) {
+    private var alreadyNotified = false
+
+    fun checkConnectionStatus(ws: Workspace, agent: WorkspaceAgent) {
+        if (alreadyNotified) {
+            return
+        }
+
+        val isWorkspaceRunning = ws.latestBuild.status == WorkspaceStatus.RUNNING
+        val isAgentReady = agent.lifecycleState == WorkspaceAgentLifecycleState.READY
+        val hasConnectionIssue = agent.status in setOf(
+            WorkspaceAgentStatus.DISCONNECTED,
+            WorkspaceAgentStatus.TIMEOUT
+        )
+
+        when {
+            isWorkspaceRunning && isAgentReady && hasConnectionIssue -> {
+                cs.launch {
+                    logAndShowWarning(
+                        title = "Unstable connection detected",
+                        warning = "Unstable connection between Coder server and workspace detected. Your active sessions may disconnect"
+                    )
+                }
+                alreadyNotified = true
+            }
+        }
+    }
+
+
+    private suspend fun logAndShowWarning(title: String, warning: String) {
+        logger.warn(warning)
+        ui.showSnackbar(
+            UUID.randomUUID().toString(),
+            i18n.ptrl(title),
+            i18n.ptrl(warning),
+            i18n.ptrl("OK")
+        )
+    }
+}

src/main/resources/localization/defaultMessages.po

@@ -191,4 +191,10 @@ msgid "Workspace name"
 msgstr ""
 
 msgid "Use app name as main page title instead of URL"
+msgstr ""
+
+msgid "Unstable connection detected"
+msgstr ""
+
+msgid "Unstable connection between Coder server and workspace detected. Your active sessions may disconnect"
 msgstr ""

src/test/kotlin/com/coder/toolbox/cli/CoderCLIManagerTest.kt

@@ -23,6 +23,7 @@ import com.coder.toolbox.store.NETWORK_INFO_DIR
 import com.coder.toolbox.store.SSH_CONFIG_OPTIONS
 import com.coder.toolbox.store.SSH_CONFIG_PATH
 import com.coder.toolbox.store.SSH_LOG_DIR
+import com.coder.toolbox.util.ConnectionMonitoringService
 import com.coder.toolbox.util.InvalidVersionException
 import com.coder.toolbox.util.OS
 import com.coder.toolbox.util.SemVer
@@ -100,7 +101,9 @@ internal class CoderCLIManagerTest {
 
             override fun removeProxyChangeListener(listener: Runnable) {
             }
-        })
+        },
+        mockk<ConnectionMonitoringService>()
+    )
 
     @BeforeTest
     fun setup() {

src/test/kotlin/com/coder/toolbox/sdk/CoderRestClientTest.kt

@@ -18,6 +18,7 @@ import com.coder.toolbox.store.CoderSecretsStore
 import com.coder.toolbox.store.CoderSettingsStore
 import com.coder.toolbox.store.TLS_ALTERNATE_HOSTNAME
 import com.coder.toolbox.store.TLS_CA_PATH
+import com.coder.toolbox.util.ConnectionMonitoringService
 import com.coder.toolbox.util.pluginTestSettingsStore
 import com.coder.toolbox.util.sslContextFromPEMs
 import com.jetbrains.toolbox.api.core.diagnostics.Logger
@@ -122,7 +123,9 @@ class CoderRestClientTest {
 
             override fun removeProxyChangeListener(listener: Runnable) {
             }
-        })
+        },
+        mockk<ConnectionMonitoringService>()
+    )
 
 
     data class TestWorkspace(var workspace: Workspace, var resources: List<WorkspaceResource>? = emptyList())

src/test/kotlin/com/coder/toolbox/util/CoderProtocolHandlerTest.kt

@@ -50,7 +50,8 @@ internal class CoderProtocolHandlerTest {
         mockk<LocalizableStringFactory>(relaxed = true),
         CoderSettingsStore(pluginTestSettingsStore(), Environment(), mockk<Logger>(relaxed = true)),
         mockk<CoderSecretsStore>(),
-        mockk<ToolboxProxySettings>()
+        mockk<ToolboxProxySettings>(),
+        mockk<ConnectionMonitoringService>()
     )
 
     private val protocolHandler = CoderProtocolHandler(