feat: activitypub actor endpoint for user accounts

src/activitypub.js

@@ -0,0 +1,42 @@
+'use strict';
+
+const { generateKeyPairSync } = require('crypto');
+
+const winston = require('winston');
+
+const db = require('./database');
+
+const ActivityPub = module.exports;
+
+ActivityPub.getPublicKey = async (uid) => {
+	let publicKey;
+
+	try {
+		({ publicKey } = await db.getObject(`uid:${uid}:keys`));
+	} catch (e) {
+		({ publicKey } = await generateKeys(uid));
+	}
+
+	return publicKey;
+};
+
+async function generateKeys(uid) {
+	winston.info(`[activitypub] Generating RSA key-pair for uid ${uid}`);
+	const {
+		publicKey,
+		privateKey,
+	} = generateKeyPairSync('rsa', {
+		modulusLength: 2048,
+		publicKeyEncoding: {
+			type: 'spki',
+			format: 'pem',
+		},
+		privateKeyEncoding: {
+			type: 'pkcs8',
+			format: 'pem',
+		},
+	});
+
+	await db.setObject(`uid:${uid}:keys`, { publicKey, privateKey });
+	return { publicKey, privateKey };
+}