Merge branch 'ephemeral' into 'main'

pipeline: improve error handling, include special treatment for ephemeral and NIP-46 events

See merge request soapbox-pub/ditto!576

src/pipeline.ts

@@ -33,31 +33,65 @@ const console = new Stickynotes('ditto:pipeline');
 async function handleEvent(event: DittoEvent, signal: AbortSignal): Promise<void> {
   // Integer max value for Postgres. TODO: switch to a bigint in 2038.
   if (event.created_at >= 2_147_483_647) {
-    throw new RelayError('blocked', 'event too far in the future');
+    throw new RelayError('invalid', 'event too far in the future');
   }
+  // Integer max value for Postgres.
   if (event.kind >= 2_147_483_647) {
-    throw new RelayError('blocked', 'event kind too large');
+    throw new RelayError('invalid', 'event kind too large');
   }
-  if (!(await verifyEventWorker(event))) return;
-  if (encounterEvent(event)) return;
-
-  console.info(`NostrEvent<${event.kind}> ${event.id}`);
-  pipelineEventsCounter.inc({ kind: event.kind });
-
+  // The only point of ephemeral events is to stream them,
+  // so throw an error if we're not even going to do that.
+  if (NKinds.ephemeral(event.kind) && !isFresh(event)) {
+    throw new RelayError('invalid', 'event too old');
+  }
+  // Block NIP-70 events, because we have no way to `AUTH`.
   if (isProtectedEvent(event)) {
     throw new RelayError('invalid', 'protected event');
   }
+  // Validate the event's signature.
+  if (!(await verifyEventWorker(event))) {
+    throw new RelayError('invalid', 'invalid signature');
+  }
+  // Skip events that have been recently encountered.
+  // We must do this after verifying the signature.
+  if (encounterEvent(event)) {
+    throw new RelayError('duplicate', 'already have this event');
+  }
 
-  if (event.kind !== 24133 && event.pubkey !== Conf.pubkey) {
+  // Log the event.
+  console.info(`NostrEvent<${event.kind}> ${event.id}`);
+  pipelineEventsCounter.inc({ kind: event.kind });
+
+  // NIP-46 events get special treatment.
+  // They are exempt from policies and other side-effects, and should be streamed out immediately.
+  // If streaming fails, an error should be returned.
+  if (event.kind === 24133) {
+    await streamOut(event);
+    return;
+  }
+
+  // Ensure the event doesn't violate the policy.
+  if (event.pubkey !== Conf.pubkey) {
     await policyFilter(event, signal);
   }
 
+  // Prepare the event for additional checks.
+  // FIXME: This is kind of hacky. Should be reorganized to fetch only what's needed for each stage.
   await hydrateEvent(event, signal);
 
+  // Ensure that the author is not banned.
   const n = getTagSet(event.user?.tags ?? [], 'n');
-
   if (n.has('disabled')) {
-    throw new RelayError('blocked', 'user is disabled');
+    throw new RelayError('blocked', 'author is blocked');
+  }
+
+  // Ephemeral events must throw if they are not streamed out.
+  if (NKinds.ephemeral(event.kind)) {
+    await Promise.all([
+      streamOut(event),
+      webPush(event),
+    ]);
+    return;
   }
 
   const kysely = await Storages.kysely();
@@ -130,7 +164,7 @@ async function hydrateEvent(event: DittoEvent, signal: AbortSignal): Promise<voi
 }
 
 /** Maybe store the event, if eligible. */
-async function storeEvent(event: DittoEvent, signal?: AbortSignal): Promise<undefined> {
+async function storeEvent(event: NostrEvent, signal?: AbortSignal): Promise<undefined> {
   if (NKinds.ephemeral(event.kind)) return;
   const store = await Storages.db();
 
@@ -217,20 +251,22 @@ async function setLanguage(event: NostrEvent): Promise<void> {
 
 /** Determine if the event is being received in a timely manner. */
 function isFresh(event: NostrEvent): boolean {
-  return eventAge(event) < Time.seconds(10);
+  return eventAge(event) < Time.minutes(1);
 }
 
 /** Distribute the event through active subscriptions. */
 async function streamOut(event: NostrEvent): Promise<void> {
-  if (isFresh(event)) {
-    const pubsub = await Storages.pubsub();
-    await pubsub.event(event);
+  if (!isFresh(event)) {
+    throw new RelayError('invalid', 'event too old');
   }
+
+  const pubsub = await Storages.pubsub();
+  await pubsub.event(event);
 }
 
 async function webPush(event: NostrEvent): Promise<void> {
   if (!isFresh(event)) {
-    return;
+    throw new RelayError('invalid', 'event too old');
   }
 
   const kysely = await Storages.kysely();