const url = require("url"); const express = require("express"); const proxy = require("express-http-proxy"); const { NodeClient } = require("hs-client"); const host = process.env.HOSTNAME || "0.0.0.0"; const port = Number(process.env.PORT) || 3100; const hsdNetworkType = process.env.HSD_NETWORK || "regtest"; const hsdHost = process.env.HSD_HOST || "localhost"; const hsdPort = Number(process.env.HSD_PORT) || 12037; const hsdApiKey = process.env.HSD_API_KEY || "foo"; const clientOptions = { network: hsdNetworkType, host: hsdHost, port: hsdPort, apiKey: hsdApiKey, }; const client = new NodeClient(clientOptions); const startsWithSkylinkRegExp = /^[a-zA-Z0-9_-]{46}/; const getDomainRecords = async (name) => { const response = await client.execute("getnameresource", [name]); const records = response?.records ?? null; console.log(`${name} => ${JSON.stringify(records)}`); return records; }; const findSkylinkRecord = (records) => { return records?.find(({ txt }) => txt?.some((entry) => isValidSkylink(entry))); }; const getSkylinkFromRecord = (record) => { return record?.txt?.find((entry) => isValidSkylink(entry)); }; const resolveDomainHandler = async (req, res) => { try { const records = await getDomainRecords(req.params.name); if (!records) return res.status(404).send(`No records found for ${req.params.name}`); const record = findSkylinkRecord(records); if (!record) throw new Error(`No skylink found in dns records of ${req.params.name}`); const skylink = getSkylinkFromRecord(record); return res.json({ skylink }); } catch (error) { res.status(500).send(`Handshake error: ${error.message}`); } }; // Checks if the given string is a valid Sia link. function isValidSkylink(link) { if (!link || link.length === 0) { return false; } return Boolean(link.match(startsWithSkylinkRegExp)); } const server = express(); server.use( "/hns/:name", proxy("nginx", { // eslint-disable-next-line no-unused-vars userResHeaderDecorator(headers, userReq, userRes, proxyReq, proxyRes) { if (headers.location && headers.location.match(startsWithSkylinkRegExp)) { headers.location = headers.location.replace(startsWithSkylinkRegExp, `/hns/${userReq.params.name}`); } return headers; }, proxyReqPathResolver: async (req) => { const records = await getDomainRecords(req.params.name); if (!records) throw new Error(`No records found for ${req.params.name}`); const record = findSkylinkRecord(records); if (!record) throw new Error(`No skylink found in dns records of ${req.params.name}`); const skylink = getSkylinkFromRecord(record); const basepath = url.resolve("/", skylink); // make the url absolute const subpath = req.url.slice(1); // drop the leading slash // if the record is just a raw skylink, replace baseUrl with /skylink if (skylink.length === 46) { return req.originalUrl.replace(req.baseUrl, basepath); } // if the record contains more than a skylink then it needs to be resolved return url.resolve(basepath, subpath); }, }) ); server.get("/hnsres/:name", resolveDomainHandler); server.listen(port, host, (error) => { if (error) throw error; console.info(`API will look for HSD Server at ${hsdHost}:${hsdPort}, "${hsdNetworkType}" network.`); console.info(`Server listening at http://${host}:${port}`); });