fix: Split Discover to only display if no current connection (#188)

* Splits the Discover plugin into 2:
 * Discover Core: preferences and header menu (always active)
 * Discover: page dashboad component (only active if no current connection)

* discover-core
 * Moves preferences to this plugin
 * Moves header menu to this plugin
 * Adds as a new plugin, always active
 * By not including a plugin-path, the plugin will not be listed in the
   nav sidebar

* discover
 * Dashboard only active if the connect-server does not contain a current
   connection

packages/online-shell/src/bootstrap.tsx

@@ -18,6 +18,7 @@ import ReactDOM from 'react-dom/client'
 import { discover } from './discover'
 import { reportWebVitals } from './reportWebVitals'
 import { HAWTIO_ONLINE_VERSION } from './constants'
+import { discoverCore } from './discover-core'
 
 configManager.addProductInfo('Hawtio Online', HAWTIO_ONLINE_VERSION)
 
@@ -38,7 +39,10 @@ springboot()
 
 // Register kubernetes & management - only then complete hawtio bootstrap
 isMgmtApiRegistered().then(() => {
-  // Register discover plugin
+  // Register discover-core plugin
+  discoverCore()
+
+  // Register discover UI plugin
   discover()
 
   // Bootstrap Hawtio

packages/online-shell/src/discover-core/globals.ts

@@ -0,0 +1,4 @@
+import { Logger } from '@hawtio/react'
+
+export const pluginName = 'hawtio-online-discover-core'
+export const log = Logger.get(pluginName)

packages/online-shell/src/discover-core/index.ts

@@ -0,0 +1,26 @@
+import { hawtio, HawtioPlugin, preferencesRegistry } from '@hawtio/react'
+import { HeaderMenuDropDown } from './HeaderMenuDropDown'
+import { DiscoverPreferences } from './DiscoverPreferences'
+
+const pluginId = 'discover-core'
+const pluginTitle = 'Discover'
+
+/*
+ * Discover core plugin, always enabled, provides:
+ * - preferences for managing the polling of pods in master
+ * - the universal header menu listing all the pods
+ *
+ * No plugin-path since it is not required to display a
+ * link in the nav-bar to display a main component
+ */
+
+export const discoverCore: HawtioPlugin = () => {
+  hawtio.addPlugin({
+    id: pluginId,
+    title: pluginTitle,
+    headerItems: [{ component: HeaderMenuDropDown, universal: true }],
+    isActive: async () => true,
+  })
+
+  preferencesRegistry.add(pluginId, pluginTitle, DiscoverPreferences)
+}

packages/online-shell/src/discover/index.ts

@@ -1,8 +1,6 @@
-import { hawtio, HawtioPlugin, preferencesRegistry } from '@hawtio/react'
+import { hawtio, HawtioPlugin, connectService } from '@hawtio/react'
 import { pluginPath } from './globals'
 import { Discover } from './Discover'
-import { HeaderMenuDropDown } from './HeaderMenuDropDown'
-import { DiscoverPreferences } from './DiscoverPreferences'
 
 const pluginId = 'discover'
 const pluginTitle = 'Discover'
@@ -13,9 +11,10 @@ export const discover: HawtioPlugin = () => {
     title: pluginTitle,
     path: pluginPath,
     component: Discover,
-    headerItems: [{ component: HeaderMenuDropDown, universal: true }],
-    isActive: async () => true,
+    isActive: async () => {
+      // Only active is there is NO current connection
+      const connection = await connectService.getCurrentConnection()
+      return !connection
+    },
   })
-
-  preferencesRegistry.add(pluginId, pluginTitle, DiscoverPreferences)
 }