Render the forum shell, resources and contacts on the server

src/lib/ssr/relay.ts

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+import { SimplePool } from "@nostr/tools";
+import type { Event } from "@nostr/tools/core";
+import type { Filter } from "@nostr/tools/filter";
+import { RELAY_URL } from "$lib/config";
+import { PROFILE_RELAYS } from "$lib/forum/profiles";
+import type { Query } from "$lib/forum/query";
+
+// Anonymous relay access for server rendering. The server has no signer, so
+// it only ever sees what the relay serves the public; members get their
+// private rooms once the client takes over. Every query is bounded so a slow
+// relay degrades to an empty page, never a hung request, and results are
+// cached briefly to absorb crawler bursts.
+const QUERY_TIMEOUT = 2500;
+const PROFILE_TIMEOUT = 1500;
+const CACHE_TTL = 30_000;
+const CACHE_MAX = 2000;
+
+const pool = new SimplePool();
+const cache = new Map<string, { at: number; result: Promise<Event[]> }>();
+
+// Resolve at EOSE from every relay or at the deadline, whichever comes first,
+// with whatever arrived: a stalled relay must not cost the events the others
+// already delivered.
+function boundedQuery(
+  relays: string[],
+  filter: Filter,
+  maxWait: number,
+): Promise<Event[]> {
+  return new Promise((resolve) => {
+    const events: Event[] = [];
+    let done = false;
+    let sub: { close(): void } | null = null;
+    const finish = () => {
+      if (done) return;
+      done = true;
+      clearTimeout(timer);
+      sub?.close();
+      resolve(events);
+    };
+    const timer = setTimeout(finish, maxWait);
+    try {
+      sub = pool.subscribeMany(relays, filter, {
+        onevent: (e) => events.push(e),
+        oneose: finish,
+      });
+      if (done) sub.close(); // EOSE fired synchronously
+    } catch {
+      finish();
+    }
+  });
+}
+
+function cachedQuery(
+  relays: string[],
+  filter: Filter,
+  maxWait: number,
+): Promise<Event[]> {
+  const key = relays.join(",") + "|" + JSON.stringify(filter);
+  const now = Date.now();
+  const hit = cache.get(key);
+  if (hit && now - hit.at < CACHE_TTL) return hit.result;
+  if (cache.size >= CACHE_MAX) cache.clear();
+  const result = boundedQuery(relays, filter, maxWait);
+  cache.set(key, { at: now, result });
+  return result;
+}
+
+export const forumQuery: Query = (filter) =>
+  cachedQuery([RELAY_URL], filter, QUERY_TIMEOUT);
+
+// Profiles mostly live off the forum relay; ask it too for members who only
+// published there.
+export const profileQuery: Query = (filter) =>
+  cachedQuery([RELAY_URL, ...PROFILE_RELAYS], filter, PROFILE_TIMEOUT);

src/lib/ssr/shell.ts

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+import { MODE, GROUP_ID } from "$lib/config";
+import { fetchGroup, fetchGroups, fetchRoomAdmins } from "$lib/forum/groups";
+import { fetchResources } from "$lib/forum/resources";
+import { fetchPartials } from "$lib/forum/partials";
+import type { ForumShell } from "$lib/forum/snapshot";
+import { forumQuery } from "./relay";
+
+// Everything the layout needs on every page: the group(s), the admin set,
+// sidebar resources and partials.
+export async function loadShell(): Promise<ForumShell> {
+  const [group, groups, resources, partials] = await Promise.all([
+    MODE === "simple" ? fetchGroup(forumQuery, GROUP_ID) : null,
+    MODE === "full" ? fetchGroups(forumQuery) : [],
+    fetchResources(forumQuery),
+    fetchPartials(forumQuery),
+  ]);
+  const adminsByRoom =
+    MODE === "full"
+      ? await fetchRoomAdmins(
+          forumQuery,
+          groups.map((g) => g.id),
+        )
+      : {};
+  const admins =
+    MODE === "full"
+      ? [...new Set(Object.values(adminsByRoom).flat())]
+      : (group?.admins ?? []);
+  return { group, groups, adminsByRoom, admins, resources, partials };
+}