Function respond

test/proxyEnvelope.test.js:127–130

(status, obj)

    hub = http.createServer(async (req, res) => {
      const body = await readBody(req);
      const respond = (status, obj) => {
        res.writeHead(status, { 'Content-Type': 'application/json' });
        res.end(JSON.stringify(obj));
      };
      if (req.url === '/a2a/hello') {
        const err = hubValidate(body, ['hello']);
        if (err) return respond(400, { error: err });