SilverBullet pivot to become an offline-first PWA (#403)

web/syscalls/fetch.ts

@@ -1,12 +1,37 @@
 import type { SysCallMapping } from "../../plugos/system.ts";
-import { proxySyscalls } from "../../plugos/syscalls/transport.ts";
-import type { Space } from "../../common/spaces/space.ts";
+import type { HttpSpacePrimitives } from "../../common/spaces/http_space_primitives.ts";
+import {
+  performLocalFetch,
+  ProxyFetchRequest,
+  ProxyFetchResponse,
+} from "../../common/proxy_fetch.ts";
 
-export function sandboxFetchSyscalls(space: Space): SysCallMapping {
-  return proxySyscalls(
-    [
-      "sandboxFetch.fetch",
-    ],
-    (ctx, name, ...args) => space.proxySyscall(ctx.plug, name, args),
-  );
+export function sandboxFetchSyscalls(
+  httpSpacePrimitives?: HttpSpacePrimitives,
+): SysCallMapping {
+  return {
+    "sandboxFetch.fetch": async (
+      _ctx,
+      url: string,
+      options: ProxyFetchRequest,
+    ): Promise<ProxyFetchResponse> => {
+      // console.log("Got sandbox fetch ", url);
+      if (!httpSpacePrimitives) {
+        // No SB server to proxy the fetch available so let's execute the request directly
+        return performLocalFetch(url, options);
+      }
+      const resp = httpSpacePrimitives.authenticatedFetch(
+        httpSpacePrimitives.url,
+        {
+          method: "POST",
+          body: JSON.stringify({
+            operation: "fetch",
+            url,
+            options,
+          }),
+        },
+      );
+      return (await resp).json();
+    },
+  };
 }