Refactor PolicyWorker error handling

src/workers/policy.ts

@@ -1,3 +1,4 @@
+import { NostrEvent, NostrRelayOK, NPolicy } from '@nostrify/nostrify';
 import { Stickynotes } from '@soapbox/stickynotes';
 import * as Comlink from 'comlink';
 
@@ -8,35 +9,67 @@ import '@/workers/handlers/abortsignal.ts';
 
 const console = new Stickynotes('ditto:policy');
 
-export const policyWorker = Comlink.wrap<CustomPolicy>(
-  new Worker(
-    new URL('./policy.worker.ts', import.meta.url),
-    {
-      type: 'module',
-      deno: {
-        permissions: {
-          read: [Conf.denoDir, Conf.policy, Conf.dataDir],
-          write: [Conf.dataDir],
-          net: 'inherit',
-          env: false,
-        },
-      },
-    },
-  ),
-);
+class PolicyWorker implements NPolicy {
+  private worker: Comlink.Remote<CustomPolicy>;
+  private ready: Promise<void>;
+  private enabled = true;
 
-try {
-  await policyWorker.init({
-    path: Conf.policy,
-    cwd: Deno.cwd(),
-    databaseUrl: Conf.databaseUrl,
-    adminPubkey: Conf.pubkey,
-  });
-  console.debug(`Using custom policy: ${Conf.policy}`);
-} catch (e: any) {
-  if (e.message.includes('Module not found')) {
-    console.debug('Custom policy not found <https://docs.soapbox.pub/ditto/policies/>');
-  } else {
-    throw new Error(`DITTO_POLICY (error importing policy): ${Conf.policy}`, e);
+  constructor() {
+    this.worker = Comlink.wrap<CustomPolicy>(
+      new Worker(
+        new URL('./policy.worker.ts', import.meta.url),
+        {
+          type: 'module',
+          deno: {
+            permissions: {
+              read: [Conf.denoDir, Conf.policy, Conf.dataDir],
+              write: [Conf.dataDir],
+              net: 'inherit',
+              env: false,
+            },
+          },
+        },
+      ),
+    );
+
+    this.ready = this.init();
+  }
+
+  async call(event: NostrEvent, signal?: AbortSignal): Promise<NostrRelayOK> {
+    await this.ready;
+
+    if (!this.enabled) {
+      return ['OK', event.id, true, ''];
+    }
+
+    return this.worker.call(event, signal);
+  }
+
+  private async init(): Promise<void> {
+    try {
+      await this.worker.init({
+        path: Conf.policy,
+        databaseUrl: Conf.databaseUrl,
+        adminPubkey: Conf.pubkey,
+      });
+
+      console.warn(`Using custom policy: ${Conf.policy}`);
+    } catch (e) {
+      if (e instanceof Error && e.message.includes('Module not found')) {
+        console.warn('Custom policy not found <https://docs.soapbox.pub/ditto/policies/>');
+        this.enabled = false;
+        return;
+      }
+
+      if (e instanceof Error && e.message.includes('PGlite is not supported in worker threads')) {
+        console.warn('Custom policies are not supported with PGlite. The policy is disabled.');
+        this.enabled = false;
+        return;
+      }
+
+      throw new Error(`DITTO_POLICY (error importing policy): ${Conf.policy}`, e);
+    }
   }
 }
+
+export const policyWorker = new PolicyWorker();