Recognize unuploaded dispatch scripts when provisioning Durable Objects

Author: cpojer

platform/packages/api/src/provisioning/durable-objects.ts

@@ -60,7 +60,17 @@ function marker(
 
 async function readBindings(env: Env, worker: string): Promise<Array<Binding> | undefined> {
   try {
-    return await cfFetch<Array<Binding>>(`${url(env, worker)}/bindings`, env.CF_API_TOKEN);
+    const bindings = await cfFetch<Array<Binding>>(
+      `${url(env, worker)}/bindings`,
+      env.CF_API_TOKEN,
+    );
+    // Dispatch can return an empty binding list for a script without a Worker.
+    // Confirm absence before provisioning; an existing unmarked Worker must
+    // still fail the ownership check.
+    if (bindings.length === 0) {
+      await cfFetch(`${url(env, worker)}/settings`, env.CF_API_TOKEN);
+    }
+    return bindings;
   } catch (error) {
     if (error instanceof CloudflareApiError && error.status === 404) {
       return undefined;

platform/packages/api/test/integration/managed-durable-objects.test.ts

@@ -78,14 +78,20 @@ beforeEach(async () => {
     const name = /\/scripts\/([^/?]+)/.exec(url)?.[1];
     if (
       name?.startsWith('void-do-') &&
-      url.endsWith('/bindings') &&
+      (url.endsWith('/bindings') || url.endsWith('/settings')) &&
       !provider.state.hostScripts.has(name)
     ) {
+      if (url.endsWith('/bindings')) {
+        return cfSuccess([]);
+      }
       return Response.json(
         { success: false, errors: [{ code: 10007, message: 'script not found' }] },
         { status: 404 },
       );
     }
+    if (name?.startsWith('void-do-') && url.endsWith('/settings') && !init?.method) {
+      return cfSuccess({ bindings: provider.state.hostScripts.get(name)!.bindings });
+    }
     const response = await original(input, init);
     if (init?.method === 'PUT' && init.body instanceof FormData && response.ok && name) {
       const metadata = JSON.parse(await (init.body.get('metadata') as Blob).text()) as Record<
@@ -190,6 +196,21 @@ function currentRelease(worker: string) {
 }
 
 describe('managed native Durable Objects', () => {
+  it('refuses to replace an existing Worker whose bindings are empty', async () => {
+    const worker = await durableObjectWorkerName(project.id, binding.className);
+    provider.state.hostScripts.set(worker, {
+      classes: new Map(),
+      bindings: [],
+      metadata: {},
+    });
+    const result = await deploy();
+    expect(result.events).toContainEqual(
+      expect.objectContaining({ event: 'error', message: expect.stringContaining('ownership') }),
+    );
+    expect(writes).toHaveLength(0);
+    expect(provider.state.hostScripts.get(worker)!.bindings).toEqual([]);
+  });
+
   it('runs the published class through real RPC and retains data after upgrade, rollback, and restart', async () => {
     const directory = mkdtempSync(join(tmpdir(), 'void-managed-native-'));
     let runtime: Miniflare | undefined;