FS: Fix rendering of public dashboards in MT frontend service (#115162)

* pass publicDashboardAccessToken to ST backend via bootdata

* slightly cleaner

* slightly tidy up go templating

* add HandleView middleware

pkg/services/frontend/index.html

@@ -188,6 +188,7 @@
       // Wrap in an IIFE to avoid polluting the global scope. Intentionally global-scope properties
       // are explicitly assigned to the `window` object.
       (() => {
+        const publicDashboardAccessToken = [[.PublicDashboardAccessToken]]
         // Grafana can only fail to load once
         // However, it can fail to load in multiple different places
         // To avoid double reporting the error, we use this boolean to check if we've already failed
@@ -271,9 +272,15 @@
         async function fetchBootData() {
           const queryParams = new URLSearchParams(window.location.search);
 
+          let path = '/bootdata';
+          // call a special bootdata url with the public access token
+          // this is needed to set the access token and correct org for public dashboards on the ST backend
+          if (publicDashboardAccessToken) {
+            path += `/${publicDashboardAccessToken}`;
+          }
           // pass the search params through to the bootdata request
           // this allows for overriding the theme/language etc
-          const bootDataUrl = new URL('/bootdata', window.location.origin);
+          const bootDataUrl = new URL(path, window.location.origin);
           for (const [key, value] of queryParams.entries()) {
             bootDataUrl.searchParams.append(key, value);
           }