feat: Webhook (#8457)

* feat: introduce webhook

* wip

* wip

* wip

* Update CHANGELOG.md

packages/backend/src/misc/webhook-cache.ts

@@ -0,0 +1,49 @@
+import { Webhooks } from '@/models/index.js';
+import { Webhook } from '@/models/entities/webhook.js';
+import { subsdcriber } from '../db/redis.js';
+
+let webhooksFetched = false;
+let webhooks: Webhook[] = [];
+
+export async function getActiveWebhooks() {
+	if (!webhooksFetched) {
+		webhooks = await Webhooks.findBy({
+			active: true,
+		});
+		webhooksFetched = true;
+	}
+
+	return webhooks;
+}
+
+subsdcriber.on('message', async (_, data) => {
+	const obj = JSON.parse(data);
+
+	if (obj.channel === 'internal') {
+		const { type, body } = obj.message;
+		switch (type) {
+			case 'webhookCreated':
+				if (body.active) {
+					webhooks.push(body);
+				}
+				break;
+			case 'webhookUpdated':
+				if (body.active) {
+					const i = webhooks.findIndex(a => a.id === body.id);
+					if (i > -1) {
+						webhooks[i] = body;
+					} else {
+						webhooks.push(body);
+					}
+				} else {
+					webhooks = webhooks.filter(a => a.id !== body.id);
+				}
+				break;
+			case 'webhookDeleted':
+				webhooks = webhooks.filter(a => a.id !== body.id);
+				break;
+			default:
+				break;
+		}
+	}
+});