Memorelay: normalize filters

src/filter.ts

@@ -104,6 +104,17 @@ function canFilter(filter: Filter): boolean {
   return getFilterLimit(filter) > 0;
 }
 
+/** Normalize the `limit` of each filter, and remove filters that can't produce any events. */
+function normalizeFilters<F extends Filter>(filters: F[]): F[] {
+  return filters.reduce<F[]>((acc, filter) => {
+    const limit = getFilterLimit(filter);
+    if (limit > 0) {
+      acc.push(limit === Infinity ? filter : { ...filter, limit });
+    }
+    return acc;
+  }, []);
+}
+
 export {
   type AuthorMicrofilter,
   canFilter,
@@ -116,5 +127,6 @@ export {
   isMicrofilter,
   matchDittoFilters,
   type MicroFilter,
+  normalizeFilters,
   type Relation,
 };

src/storages/memorelay.ts

@@ -1,5 +1,5 @@
 import { Debug, type Event, type Filter, LRUCache, matchFilter, matchFilters } from '@/deps.ts';
-import { canFilter, getFilterLimit } from '@/filter.ts';
+import { normalizeFilters } from '@/filter.ts';
 import { type EventStore, type GetEventsOpts } from '@/store.ts';
 
 /** In-memory data store for events. */
@@ -28,7 +28,7 @@ class Memorelay implements EventStore {
   /** Get events from memory. */
   getEvents<K extends number>(filters: Filter<K>[], opts: GetEventsOpts = {}): Promise<Event<K>[]> {
     if (opts.signal?.aborted) return Promise.resolve([]);
-    filters = filters.filter(canFilter);
+    filters = normalizeFilters(filters);
     if (!filters.length) return Promise.resolve([]);
     this.#debug('REQ', JSON.stringify(filters));
 
@@ -39,7 +39,7 @@ class Memorelay implements EventStore {
       let index = 0;
 
       for (const filter of filters) {
-        const limit = getFilterLimit(filter);
+        const limit = filter.limit ?? Infinity;
         const usage = usages[index] ?? 0;
 
         if (usage >= limit) {
@@ -52,7 +52,7 @@ class Memorelay implements EventStore {
         index++;
       }
 
-      if (filters.every((filter, index) => usages[index] >= getFilterLimit(filter))) {
+      if (filters.every((filter, index) => filter.limit && (usages[index] >= filter.limit))) {
         break;
       }
     }