refactoring

Resolve #7779

packages/backend/src/server/api/endpoints/channels/unfollow.ts

@@ -0,0 +1,45 @@
+import $ from 'cafy';
+import { ID } from '@/misc/cafy-id';
+import define from '../../define';
+import { ApiError } from '../../error';
+import { Channels, ChannelFollowings } from '@/models/index';
+import { publishUserEvent } from '@/services/stream';
+
+export const meta = {
+	tags: ['channels'],
+
+	requireCredential: true as const,
+
+	kind: 'write:channels',
+
+	params: {
+		channelId: {
+			validator: $.type(ID),
+		},
+	},
+
+	errors: {
+		noSuchChannel: {
+			message: 'No such channel.',
+			code: 'NO_SUCH_CHANNEL',
+			id: '19959ee9-0153-4c51-bbd9-a98c49dc59d6'
+		},
+	}
+};
+
+export default define(meta, async (ps, user) => {
+	const channel = await Channels.findOne({
+		id: ps.channelId,
+	});
+
+	if (channel == null) {
+		throw new ApiError(meta.errors.noSuchChannel);
+	}
+
+	await ChannelFollowings.delete({
+		followerId: user.id,
+		followeeId: channel.id,
+	});
+
+	publishUserEvent(user.id, 'unfollowChannel', channel);
+});