Federated URL backend handling

server/http_server.ts

@@ -344,6 +344,17 @@ export class HttpServer {
             response.body = "Not exposed";
             return;
           }
+          // Handle federated links through a simple redirect, only used for attachments loads with service workers disabled
+          if (name.startsWith("!")) {
+            let url = name.slice(1);
+            if (url.startsWith("localhost")) {
+              url = `http://${url}`;
+            } else {
+              url = `https://${url}`;
+            }
+            response.redirect(url);
+            return;
+          }
           try {
             const fileData = await spacePrimitives.readFile(
               name,

web/open_pages.ts

@@ -1,5 +1,5 @@
 import { Client } from "./client.ts";
-import { EditorSelection, EditorView } from "./deps.ts";
+import { EditorSelection } from "./deps.ts";
 
 class PageState {
   constructor(

web/service_worker.ts

@@ -147,6 +147,16 @@ async function handleLocalFileRequest(
         },
       },
     );
+  } else if (path.startsWith("!")) {
+    // Federated URL handling
+    let url = path.slice(1);
+    if (url.startsWith("localhost")) {
+      url = `http://${url}`;
+    } else {
+      url = `https://${url}`;
+    }
+    console.info("Proxying federated URL", path, "to", url);
+    return fetch(url, { method: "GET", headers: request.headers });
   } else {
     console.error(
       "Did not find file in locally synced space",