Improve the NIP-05 cache

src/controllers/api/search.ts

@@ -5,7 +5,7 @@ import { booleanParamSchema } from '@/schema.ts';
 import { nostrIdSchema } from '@/schemas/nostr.ts';
 import { searchStore } from '@/storages.ts';
 import { dedupeEvents } from '@/utils.ts';
-import { lookupNip05Cached } from '@/utils/nip05.ts';
+import { nip05Cache } from '@/utils/nip05.ts';
 import { renderAccount } from '@/views/mastodon/accounts.ts';
 import { renderStatus } from '@/views/mastodon/statuses.ts';
 
@@ -95,13 +95,13 @@ function typeToKinds(type: SearchQuery['type']): number[] {
 
 /** Resolve a searched value into an event, if applicable. */
 async function lookupEvent(query: SearchQuery, signal: AbortSignal): Promise<Event | undefined> {
-  const filters = await getLookupFilters(query);
+  const filters = await getLookupFilters(query, signal);
   const [event] = await searchStore.filter(filters, { limit: 1, signal });
   return event;
 }
 
 /** Get filters to lookup the input value. */
-async function getLookupFilters({ q, type, resolve }: SearchQuery): Promise<DittoFilter[]> {
+async function getLookupFilters({ q, type, resolve }: SearchQuery, signal: AbortSignal): Promise<DittoFilter[]> {
   const filters: DittoFilter[] = [];
 
   const accounts = !type || type === 'accounts';
@@ -139,9 +139,13 @@ async function getLookupFilters({ q, type, resolve }: SearchQuery): Promise<Ditt
     if (accounts) filters.push({ kinds: [0], authors: [q] });
     if (statuses) filters.push({ kinds: [1], ids: [q] });
   } else if (accounts && ACCT_REGEX.test(q)) {
-    const pubkey = await lookupNip05Cached(q);
-    if (pubkey) {
-      filters.push({ kinds: [0], authors: [pubkey], relations: ['author_stats'] });
+    try {
+      const { pubkey } = await nip05Cache.fetch(q, { signal });
+      if (pubkey) {
+        filters.push({ kinds: [0], authors: [pubkey], relations: ['author_stats'] });
+      }
+    } catch (_e) {
+      // do nothing
     }
   }
 

src/deps.ts

@@ -86,5 +86,9 @@ export { EventEmitter } from 'npm:tseep@^1.1.3';
 export { default as stringifyStable } from 'npm:fast-stable-stringify@^1.0.0';
 // @deno-types="npm:@types/debug@^4.1.12"
 export { default as Debug } from 'npm:debug@^4.3.4';
+export {
+  type MapCache,
+  NIP05,
+} from 'https://gitlab.com/soapbox-pub/nlib/-/raw/46be9e985950547574b1735d0ae52a6a7217d056/mod.ts';
 
 export type * as TypeFest from 'npm:type-fest@^4.3.0';

src/utils.ts

@@ -1,6 +1,6 @@
 import { type Event, type EventTemplate, getEventHash, nip19, z } from '@/deps.ts';
 import { getAuthor } from '@/queries.ts';
-import { lookupNip05Cached } from '@/utils/nip05.ts';
+import { nip05Cache } from '@/utils/nip05.ts';
 import { nostrIdSchema } from '@/schemas/nostr.ts';
 
 /** Get the current time in Nostr format. */
@@ -56,10 +56,11 @@ function parseNip05(value: string): Nip05 {
 }
 
 /** Resolve a bech32 or NIP-05 identifier to an account. */
-async function lookupAccount(value: string): Promise<Event<0> | undefined> {
+async function lookupAccount(value: string, signal = AbortSignal.timeout(3000)): Promise<Event<0> | undefined> {
   console.log(`Looking up ${value}`);
 
-  const pubkey = bech32ToPubkey(value) || await lookupNip05Cached(value);
+  const pubkey = bech32ToPubkey(value) ||
+    await nip05Cache.fetch(value, { signal }).then(({ pubkey }) => pubkey).catch(() => undefined);
 
   if (pubkey) {
     return getAuthor(pubkey);

src/utils/SimpleLRU.ts

@@ -0,0 +1,37 @@
+// deno-lint-ignore-file ban-types
+
+import { LRUCache, type MapCache } from '@/deps.ts';
+
+type FetchFn<K extends {}, V extends {}, O extends {}> = (key: K, opts: O) => Promise<V>;
+
+interface FetchFnOpts {
+  signal?: AbortSignal | null;
+}
+
+export class SimpleLRU<
+  K extends {},
+  V extends {},
+  O extends {} = FetchFnOpts,
+> implements MapCache<K, V, O> {
+  protected cache: LRUCache<K, V, void>;
+
+  constructor(fetchFn: FetchFn<K, V, { signal: AbortSignal }>, opts: LRUCache.Options<K, V, void>) {
+    this.cache = new LRUCache({
+      fetchMethod: (key, _staleValue, { signal }) => fetchFn(key, { signal: signal as AbortSignal }),
+      ...opts,
+    });
+  }
+
+  async fetch(key: K, opts?: O): Promise<V> {
+    const result = await this.cache.fetch(key, opts);
+    if (result === undefined) {
+      throw new Error('SimpleLRU: fetch failed');
+    }
+    return result;
+  }
+
+  put(key: K, value: V): Promise<void> {
+    this.cache.set(key, value);
+    return Promise.resolve();
+  }
+}

src/utils/nip05.ts

@@ -1,73 +1,22 @@
-import { Debug, TTLCache, z } from '@/deps.ts';
+import { Debug, NIP05, nip19 } from '@/deps.ts';
+import { SimpleLRU } from '@/utils/SimpleLRU.ts';
 import { Time } from '@/utils/time.ts';
-import { fetchWorker } from '@/workers/fetch.ts';
 
 const debug = Debug('ditto:nip05');
 
-const nip05Cache = new TTLCache<string, Promise<string | null>>({ ttl: Time.hours(1), max: 5000 });
-
-const NIP05_REGEX = /^(?:([\w.+-]+)@)?([\w.-]+)$/;
-
-interface LookupOpts {
-  signal?: AbortSignal;
-}
-
-/** Get pubkey from NIP-05. */
-async function lookup(value: string, opts: LookupOpts = {}): Promise<string | null> {
-  const { signal = AbortSignal.timeout(2000) } = opts;
-
-  const match = value.match(NIP05_REGEX);
-  if (!match) return null;
-
-  const [_, name = '_', domain] = match;
-
-  try {
-    const res = await fetchWorker(`https://${domain}/.well-known/nostr.json?name=${name}`, {
-      signal,
-    });
-
-    const { names } = nostrJsonSchema.parse(await res.json());
-
-    return names[name] || null;
-  } catch (e) {
-    debug(e);
-    return null;
-  }
-}
-
-/** nostr.json schema. */
-const nostrJsonSchema = z.object({
-  names: z.record(z.string(), z.string()),
-  relays: z.record(z.string(), z.array(z.string())).optional().catch(undefined),
-});
-
-/**
- * Lookup the NIP-05 and serve from cache first.
- * To prevent race conditions we put the promise in the cache instead of the result.
- */
-function lookupNip05Cached(value: string): Promise<string | null> {
-  const cached = nip05Cache.get(value);
-  if (cached !== undefined) return cached;
-
-  debug(`Lookup ${value}`);
-  const result = lookup(value);
-  nip05Cache.set(value, result);
-
-  result.then((result) => {
-    if (result) {
-      debug(`Found: ${value} is ${result}`);
-    } else {
-      debug(`Not found: ${value} is ${result}`);
+const nip05Cache = new SimpleLRU<string, nip19.ProfilePointer>(
+  async (key, { signal }) => {
+    debug(`Lookup ${key}`);
+    try {
+      const result = await NIP05.lookup(key, { fetch, signal });
+      debug(`Found: ${key} is ${result.pubkey}`);
+      return result;
+    } catch (e) {
+      debug(`Not found: ${key}`);
+      throw e;
     }
-  });
+  },
+  { max: 5000, ttl: Time.hours(1) },
+);
 
-  return result;
-}
-
-/** Verify the NIP-05 matches the pubkey, with cache. */
-async function verifyNip05Cached(value: string, pubkey: string): Promise<boolean> {
-  const result = await lookupNip05Cached(value);
-  return result === pubkey;
-}
-
-export { lookupNip05Cached, verifyNip05Cached };
+export { nip05Cache };

src/views/mastodon/accounts.ts

@@ -3,7 +3,7 @@ import { findUser } from '@/db/users.ts';
 import { lodash, nip19, type UnsignedEvent } from '@/deps.ts';
 import { jsonMetaContentSchema } from '@/schemas/nostr.ts';
 import { type DittoEvent } from '@/storages/types.ts';
-import { verifyNip05Cached } from '@/utils/nip05.ts';
+import { nip05Cache } from '@/utils/nip05.ts';
 import { Nip05, nostrDate, nostrNow, parseNip05 } from '@/utils.ts';
 import { renderEmojis } from '@/views/mastodon/emojis.ts';
 
@@ -86,9 +86,19 @@ function accountFromPubkey(pubkey: string, opts: ToAccountOpts = {}) {
   return renderAccount(event, opts);
 }
 
-async function parseAndVerifyNip05(nip05: string | undefined, pubkey: string): Promise<Nip05 | undefined> {
-  if (nip05 && await verifyNip05Cached(nip05, pubkey)) {
-    return parseNip05(nip05);
+async function parseAndVerifyNip05(
+  nip05: string | undefined,
+  pubkey: string,
+  signal = AbortSignal.timeout(3000),
+): Promise<Nip05 | undefined> {
+  if (!nip05) return;
+  try {
+    const result = await nip05Cache.fetch(nip05, { signal });
+    if (result.pubkey === pubkey) {
+      return parseNip05(nip05);
+    }
+  } catch (_e) {
+    // do nothing
   }
 }