feat: fire webhooks on jetstream events, cap at 10 per DID

- db.ts: getWebhooksByDid returns the 10 most recent subscriptions (ORDER BY id DESC LIMIT 10)
- jetstream.ts: fireWebhooks fans out to registered URLs via Promise.allSettled after each create/update/delete event

jetstream.ts

@@ -2,6 +2,7 @@ import { Jetstream } from "@skyware/jetstream";
 import {
   deleteNote,
   getCursor,
+  getWebhooksByDid,
   saveCursor,
   upsertNote,
 } from "./src/data/db.ts";
@@ -16,6 +17,28 @@ globalThis.addEventListener("error", (e) => {
   log("[jetstream] uncaught error:", e.error);
 });
 
+const fireWebhooks = async (
+  did: string,
+  payload: Record<string, unknown>,
+): Promise<void> => {
+  const webhooks = getWebhooksByDid(did);
+  if (webhooks.length === 0) return;
+  const results = await Promise.allSettled(
+    webhooks.map(({ method, url }) =>
+      fetch(url, {
+        method,
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify(payload),
+      })
+    ),
+  );
+  for (const result of results) {
+    if (result.status === "rejected") {
+      log(`[jetstream] webhook error for ${did}:`, result.reason);
+    }
+  }
+};
+
 const cursor = getCursor();
 log(`[jetstream] starting with cursor: ${cursor ?? "none"}`);
 
@@ -25,36 +48,39 @@ const jetstream = new Jetstream({
   endpoint: "https://jetstream2.fr.hose.cam/subscribe"
 });
 
-jetstream.onCreate("space.remanso.note", (event) => {
+jetstream.onCreate("space.remanso.note", async (event) => {
   try {
     const { did, commit: { rkey, record } } = event;
     log(`[jetstream] creating ${did}/${rkey}...`);
     const note = record as unknown as Omit<Note, "did" | "rkey">;
     upsertNote({ did, rkey, ...note });
     log(`[jetstream] create ${did}/${rkey}: ${note.title}`);
+    await fireWebhooks(did, { event: "create", did, rkey, ...note });
   } catch (error) {
     log(`[jetstream] error on create:`, error);
   }
 });
 
-jetstream.onUpdate("space.remanso.note", (event) => {
+jetstream.onUpdate("space.remanso.note", async (event) => {
   try {
     const { did, commit: { rkey, record } } = event;
     log(`[jetstream] updating ${did}/${rkey}...`);
     const note = record as unknown as Omit<Note, "did" | "rkey">;
     upsertNote({ did, rkey, ...note });
     log(`[jetstream] update ${did}/${rkey}: ${note.title}`);
+    await fireWebhooks(did, { event: "update", did, rkey, ...note });
   } catch (error) {
     log(`[jetstream] error on update:`, error);
   }
 });
 
-jetstream.onDelete("space.remanso.note", (event) => {
+jetstream.onDelete("space.remanso.note", async (event) => {
   try {
     const { did, commit: { rkey } } = event;
     log(`[jetstream] deleting ${did}/${rkey}...`);
     deleteNote({ did, rkey });
     log(`[jetstream] delete ${did}/${rkey}`);
+    await fireWebhooks(did, { event: "delete", did, rkey });
   } catch (error) {
     log(`[jetstream] error on delete:`, error);
   }

src/data/db.ts

@@ -92,6 +92,12 @@ export const deleteWebhooksByDid = (did: string): void => {
   db.exec("DELETE FROM webhook_subscription WHERE did = ?", did);
 };
 
+export const getWebhooksByDid = (did: string): WebhookSubscriptionRow[] => {
+  return db.prepare(
+    "SELECT id, did, method, url FROM webhook_subscription WHERE did = ? ORDER BY id DESC LIMIT 10",
+  ).all<WebhookSubscriptionRow>(did);
+};
+
 export const upsertNote = (note: Note) => {
   const now = new Date().toISOString();
   db.exec(