feat: Webhook (#8457)

* feat: introduce webhook

* wip

* wip

* wip

* Update CHANGELOG.md

packages/backend/src/server/api/endpoints/i/webhooks/show.ts

@@ -0,0 +1,41 @@
+import define from '../../../define.js';
+import { ApiError } from '../../../error.js';
+import { Webhooks } from '@/models/index.js';
+
+export const meta = {
+	tags: ['webhooks'],
+
+	requireCredential: true,
+
+	kind: 'read:account',
+
+	errors: {
+		noSuchWebhook: {
+			message: 'No such webhook.',
+			code: 'NO_SUCH_WEBHOOK',
+			id: '50f614d9-3047-4f7e-90d8-ad6b2d5fb098',
+		},
+	},
+} as const;
+
+export const paramDef = {
+	type: 'object',
+	properties: {
+		webhookId: { type: 'string', format: 'misskey:id' },
+	},
+	required: ['webhookId'],
+} as const;
+
+// eslint-disable-next-line import/no-default-export
+export default define(meta, paramDef, async (ps, user) => {
+	const webhook = await Webhooks.findOneBy({
+		id: ps.webhookId,
+		userId: user.id,
+	});
+
+	if (webhook == null) {
+		throw new ApiError(meta.errors.noSuchWebhook);
+	}
+
+	return webhook;
+});