Track connectedToBackend as a setting. Use it across obsidian plugin

- Display warning at top of khoj obsidian plugin settings
- Make search command available only if connected to backend
- Show warning notice on clicking khoj search ribbon button

- Call saveData after configureKhojBackend to ensure
  connnectedToBackend setting saved after being (potentially) updated
  in configureKhojBackend function

src/interface/obsidian/src/main.ts

@@ -1,4 +1,4 @@
-import { Plugin } from 'obsidian';
+import { Notice, Plugin } from 'obsidian';
 import { KhojSetting, KhojSettingTab, DEFAULT_SETTINGS } from 'src/settings'
 import { KhojModal } from 'src/modal'
 import { configureKhojBackend } from './utils';
@@ -14,18 +14,22 @@ export default class Khoj extends Plugin {
         this.addCommand({
             id: 'search',
             name: 'Search',
-            callback: () => {
-                new KhojModal(this.app, this.settings).open();
+            checkCallback: (checking) => {
+                if (!checking && this.settings.connectedToBackend)
+                    new KhojModal(this.app, this.settings).open();
+                return this.settings.connectedToBackend;
             }
         });
 
         // Create an icon in the left ribbon.
         this.addRibbonIcon('search', 'Khoj', (_: MouseEvent) => {
             // Called when the user clicks the icon.
-            new KhojModal(this.app, this.settings).open();
+            this.settings.connectedToBackend
+            ? new KhojModal(this.app, this.settings).open()
+            : new Notice(`❗️Ensure Khoj backend is running and Khoj URL is pointing to it in the plugin settings`);
         });
 
-        // Add a settings tab so the user can configure various aspects of the plugin
+        // Add a settings tab so the user can configure khoj
         this.addSettingTab(new KhojSettingTab(this.app, this));
     }
 
@@ -41,7 +45,7 @@ export default class Khoj extends Plugin {
     }
 
     async saveSettings() {
-        await this.saveData(this.settings)
-            .then(() => configureKhojBackend(this.settings));
+        await configureKhojBackend(this.settings)
+            .then(() => this.saveData(this.settings));
     }
 }

src/interface/obsidian/src/settings.ts

@@ -6,12 +6,14 @@ export interface KhojSetting {
     resultsCount: number;
     khojUrl: string;
     obsidianVaultPath: string;
+    connectedToBackend: boolean;
 }
 
 export const DEFAULT_SETTINGS: KhojSetting = {
     resultsCount: 6,
     khojUrl: 'http://localhost:8000',
-    obsidianVaultPath: getVaultAbsolutePath()
+    obsidianVaultPath: getVaultAbsolutePath(),
+    connectedToBackend: false,
 }
 
 export class KhojSettingTab extends PluginSettingTab {
@@ -25,6 +27,13 @@ export class KhojSettingTab extends PluginSettingTab {
     display(): void {
         const { containerEl } = this;
         containerEl.empty();
+
+        // Add notice if unable to connect to khoj backend
+        if (!this.plugin.settings.connectedToBackend) {
+            containerEl.createEl('small', { text: '❗Ensure Khoj backend is running and Khoj URL is correctly set below' });
+        }
+
+        // Add khoj settings configurable from the plugin settings tab
         new Setting(containerEl)
             .setName('Vault Paths')
             .setDesc('The Obsidian Vault to search with Khoj')

src/interface/obsidian/src/utils.ts

@@ -16,13 +16,15 @@ export async function configureKhojBackend(setting: KhojSetting) {
     // Check if khoj backend is configured, show error if backend is not running
     let khoj_already_configured = await request(khojConfigUrl)
         .then(response => {
+            setting.connectedToBackend = true;
             return response !== "null"
         })
         .catch(error => {
-            new Notice(`❗️Ensure Khoj backend is running and Khoj URL is pointing to it in the Khoj plugin settings.\n\n${error}`);
+            setting.connectedToBackend = false;
+            new Notice(`❗️Ensure Khoj backend is running and Khoj URL is pointing to it in the plugin settings.\n\n${error}`);
         })
     // Short-circuit configuring khoj if unable to connect to khoj backend
-    if (khoj_already_configured === null) return;
+    if (!setting.connectedToBackend) return;
 
     // Get current config if khoj backend configured, else get default config from khoj backend
     await request(khoj_already_configured ? khojConfigUrl : `${khojConfigUrl}/default`)