[WIP] Add extra check for dashboards behind auth

schema/plugin.json

@@ -20,6 +20,12 @@
       "title": "Hide Cluster Manager",
       "description": "Some deployments don't want to or are unable to use the cluster manager feature. Toggle to hide it from the user interface (note: this does not disable the underlying functionality).",
       "default": false
+    },
+    "browserDashboardCheck": {
+      "type": "boolean",
+      "title": "Determine whether to validate dashboards via browser check.",
+      "description": "If set to true, the test dashboard will be validated within the browser environment. This is useful for testing the dashboard when behind a browser-cookie based authentication.",
+      "default": false
     }
   },
   "type": "object"

src/dashboard.tsx

@@ -266,19 +266,21 @@ export class URLInput extends Widget {
     if (newValue === oldValue.url) {
       return;
     }
-    void Private.testDaskDashboard(newValue, this._serverSettings).then(
-      result => {
-        this._urlInfo = result;
-        this._urlChanged.emit({ oldValue, newValue: result });
-        this._input.blur();
-        this.update();
-        if (!result) {
-          console.warn(
-            `${newValue} does not appear to host a valid Dask dashboard`
-          );
-        }
+    void Private.testDaskDashboard(
+      newValue,
+      this._serverSettings,
+      this._browserDashboardCheck
+    ).then(result => {
+      this._urlInfo = result;
+      this._urlChanged.emit({ oldValue, newValue: result });
+      this._input.blur();
+      this.update();
+      if (!result) {
+        console.warn(
+          `${newValue} does not appear to host a valid Dask dashboard`
+        );
       }
-    );
+    });
   }
 
   /**
@@ -296,6 +298,16 @@ export class URLInput extends Widget {
     return this._urlChanged;
   }
 
+  /**
+   * The in browser dashboard check for authenticated dashboards.
+   */
+  get browserDashboardCheck(): boolean {
+    return this._browserDashboardCheck;
+  }
+  set browserDashboardCheck(value: boolean) {
+    this._browserDashboardCheck = value;
+  }
+
   /**
    * Dispose of the resources held by the dashboard.
    */
@@ -393,6 +405,7 @@ export class URLInput extends Widget {
   private _urlInfo: DashboardURLInfo = { isActive: false, url: '', plots: {} };
   private _input: HTMLInputElement;
   private _poll: Poll;
+  private _browserDashboardCheck: boolean = false;
   private _serverSettings: ServerConnection.ISettings;
 }
 
@@ -572,7 +585,8 @@ namespace Private {
    */
   export async function testDaskDashboard(
     url: string,
-    settings: ServerConnection.ISettings
+    settings: ServerConnection.ISettings,
+    browserDashboardCheck: boolean = false
   ): Promise<DashboardURLInfo> {
     url = normalizeDashboardUrl(url, settings.baseUrl);
 
@@ -607,6 +621,31 @@ namespace Private {
             plots: {}
           };
         });
+    } else if (browserDashboardCheck) {
+      return fetch(URLExt.join(url, 'individual-plots.json'))
+        .then(async response => {
+          if (response.status === 200) {
+            const plots = (await response.json()) as { [plot: string]: string };
+            return {
+              url,
+              isActive: true,
+              plots
+            };
+          } else {
+            return {
+              url,
+              isActive: false,
+              plots: {}
+            };
+          }
+        })
+        .catch(() => {
+          return {
+            url,
+            isActive: false,
+            plots: {}
+          };
+        });
     }
 
     const response = await ServerConnection.makeRequest(

src/index.ts

@@ -282,6 +282,10 @@ async function activate(
   // or are unable to use it.
   let hideClusterManager: boolean = false;
 
+  // Whether to test the Dask dashboard using a fetch request or to proceed
+  // with default behavior.
+  let browserDashboardCheck: boolean = false;
+
   // Update the existing trackers and signals in light of a change to the
   // settings system. In particular, this reacts to a change in the setting
   // for auto-starting cluster client.
@@ -343,6 +347,11 @@ async function activate(
         autoStartClient = settings.get('autoStartClient').composite as boolean;
         updateTrackers();
 
+        // Determine whether to validate dashboards via browser check.
+        browserDashboardCheck = settings.get('browserDashboardCheck')
+          .composite as boolean;
+        sidebar.dashboardLauncher.input.browserDashboardCheck = browserDashboardCheck;
+
         //Determine whether to hide the cluster manager
         hideClusterManager = settings.get('hideClusterManager')
           .composite as boolean;