Memorelay: do some premature optimizations

src/storages/memorelay.ts

@@ -1,4 +1,4 @@
-import { Debug, type Event, type Filter, LRUCache, matchFilter, matchFilters } from '@/deps.ts';
+import { Debug, type Event, type Filter, LRUCache, matchFilter } from '@/deps.ts';
 import { normalizeFilters } from '@/filter.ts';
 import { type EventStore, type GetEventsOpts } from '@/store.ts';
 
@@ -27,32 +27,62 @@ 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 = normalizeFilters(filters);
+
+    if (opts.signal?.aborted) return Promise.resolve([]);
     if (!filters.length) return Promise.resolve([]);
+
     this.#debug('REQ', JSON.stringify(filters));
 
+    /** Event results to return. */
     const results: Event<K>[] = [];
-    const usages: number[] = [];
 
+    /** Number of times an event has been added to results for each filter. */
+    const filterUsages: number[] = [];
+
+    /** Check if all filters have been satisfied. */
+    function checkSatisfied() {
+      return results.length >= (opts.limit ?? Infinity) ||
+        filters.every((filter, index) => filter.limit && (filterUsages[index] >= filter.limit));
+    }
+
+    // Optimize for filters with IDs.
+    filters.forEach((filter, index) => {
+      if (filter.ids) {
+        for (const id of filter.ids) {
+          const event = this.#cache.get(id);
+          if (event && matchFilter(filter, event)) {
+            results.push(event as Event<K>);
+          }
+        }
+        filterUsages[index] = Infinity;
+      }
+    });
+
+    // Return early if all filters are satisfied.
+    if (checkSatisfied()) {
+      return Promise.resolve(results);
+    }
+
+    // Seek through all events in memory.
     for (const event of this.#events()) {
-      let index = 0;
-
-      for (const filter of filters) {
+      filters.forEach((filter, index) => {
         const limit = filter.limit ?? Infinity;
-        const usage = usages[index] ?? 0;
+        const usage = filterUsages[index] ?? 0;
 
         if (usage >= limit) {
-          continue;
+          return;
         } else if (matchFilter(filter, event)) {
           results.push(event as Event<K>);
-          usages[index] = usage + 1;
+          this.#cache.get(event.id);
+          filterUsages[index] = usage + 1;
         }
 
         index++;
-      }
+      });
 
-      if (filters.every((filter, index) => filter.limit && (usages[index] >= filter.limit))) {
+      // Check after each event if we can return.
+      if (checkSatisfied()) {
         break;
       }
     }
@@ -73,11 +103,9 @@ class Memorelay implements EventStore {
   }
 
   /** Delete events from memory. */
-  deleteEvents(filters: Filter[]): Promise<void> {
-    for (const event of this.#events()) {
-      if (matchFilters(filters, event)) {
-        this.#cache.delete(event.id);
-      }
+  async deleteEvents(filters: Filter[]): Promise<void> {
+    for (const event of await this.getEvents(filters)) {
+      this.#cache.delete(event.id);
     }
     return Promise.resolve();
   }