feat: note attachments via link preview plugin

src/posts/attachments.js

@@ -0,0 +1,54 @@
+'use strict';
+
+const crypto = require('crypto');
+
+const db = require('../database');
+
+const Attachments = module.exports;
+
+Attachments.get = async (pid) => {
+	const hashes = await db.getSortedSetMembers(`post:${pid}:attachments`);
+	const keys = hashes.map(hash => `attachment:${hash}`);
+	const attachments = (await db.getObjects(keys)).filter(Boolean);
+
+	return attachments;
+};
+
+Attachments.update = async (pid, attachments) => {
+	if (!attachments) {
+		return;
+	}
+
+	const bulkOps = {
+		hash: [],
+		zset: {
+			score: [],
+			value: [],
+		},
+	};
+
+	attachments.filter(Boolean).forEach(({ _type, mediaType, url, name, width, height }, idx) => {
+		if (!url) { // only required property
+			return;
+		}
+
+		const hash = crypto.createHash('sha256').update(url).digest('hex');
+		const key = `attachment:${hash}`;
+
+		if (_type) {
+			_type = 'attachment';
+		}
+
+		bulkOps.hash.push([key, { _type, mediaType, url, name, width, height }]);
+		bulkOps.zset.score.push(idx);
+		bulkOps.zset.value.push(hash);
+	});
+
+	await Promise.all([
+		db.setObjectBulk(bulkOps.hash),
+		db.sortedSetAdd(`post:${pid}:attachments`, bulkOps.zset.score, bulkOps.zset.value),
+	]);
+};
+
+// todo
+// Attachments.remove = async (pid) => { ... }

src/posts/index.js

@@ -27,6 +27,8 @@ require('./queue')(Posts);
 require('./diffs')(Posts);
 require('./uploads')(Posts);
 
+Posts.attachments = require('./attachments');
+
 Posts.exists = async function (pids) {
 	return await db.exists(
 		Array.isArray(pids) ? pids.map(pid => `post:${pid}`) : `post:${pids}`