Add hashtag timeline

src/app.ts

@@ -38,7 +38,7 @@ import {
   statusController,
 } from './controllers/api/statuses.ts';
 import { streamingController } from './controllers/api/streaming.ts';
-import { homeController, publicController } from './controllers/api/timelines.ts';
+import { hashtagTimelineController, homeController, publicController } from './controllers/api/timelines.ts';
 import { trendingTagsController } from './controllers/api/trends.ts';
 import { indexController } from './controllers/site.ts';
 import { hostMetaController } from './controllers/well-known/host-meta.ts';
@@ -109,6 +109,7 @@ app.post('/api/v1/statuses', requirePubkey, createStatusController);
 
 app.get('/api/v1/timelines/home', requirePubkey, homeController);
 app.get('/api/v1/timelines/public', publicController);
+app.get('/api/v1/timelines/tag/:hashtag', hashtagTimelineController);
 
 app.get('/api/v1/preferences', preferencesController);
 app.get('/api/v1/search', searchController);

src/controllers/api/timelines.ts

@@ -1,8 +1,10 @@
 import { z } from '@/deps.ts';
+import * as mixer from '@/mixer.ts';
 import { getFeed, getPublicFeed } from '@/queries.ts';
 import { booleanParamSchema } from '@/schema.ts';
 import { toStatus } from '@/transformers/nostr-to-mastoapi.ts';
 import { buildLinkHeader, paginationSchema } from '@/utils/web.ts';
+import { Time } from '@/utils.ts';
 
 import type { AppController } from '@/app.ts';
 
@@ -40,4 +42,23 @@ const publicController: AppController = async (c) => {
   return c.json(statuses, 200, link ? { link } : undefined);
 };
 
-export { homeController, publicController };
+const hashtagTimelineController: AppController = async (c) => {
+  const hashtag = c.req.param('hashtag')!;
+  const params = paginationSchema.parse(c.req.query());
+
+  const events = await mixer.getFilters(
+    [{ kinds: [1], '#t': [hashtag], ...params }],
+    { timeout: Time.seconds(3) },
+  );
+
+  if (!events.length) {
+    return c.json([]);
+  }
+
+  const statuses = (await Promise.all(events.map(toStatus))).filter(Boolean);
+
+  const link = buildLinkHeader(c.req.url, events);
+  return c.json(statuses, 200, link ? { link } : undefined);
+};
+
+export { hashtagTimelineController, homeController, publicController };