Responding immediately to client without forwarding to proxy

[sscarduzio]

Sometimes, for a certan combination of method, path, header, I would like to bounce back the request BEFORE it's forwarded to the server.

I'm no sure where to create this response object, and how to return it so that the request never reaches the server.

I.e.

const proxy = require('express-http-proxy');
const app = require('express')();

const port = 5000

app.use(proxy('localhost:9200', {
  https: true,
  preserveHostHdr: true,
  parseReqBody: false,

  proxyErrorHandler: function (err, res, next) {
    if (err) console.log("ERROR!  ", err)
    next(err);
  },

  proxyReqPathResolver: function (req) {
    console.log("> "+req.method + " ",req.url)
    return req.url
  },
  
  proxyReqOptDecorator: function (proxyReqOpts, srcReq) {
    // letting self signed ssl cert go through
    proxyReqOpts.rejectUnauthorized = false
    
    if(srcReq.path.indexOf("siem")>=0 && srcReq.method == 'PUT' && srcReq.statusCode == 400){
      console.log("responding immediately with a 200...")
       // return ???????? <--- I don't want this request to reach the server!
    }
    return proxyReqOpts;
  }

}));

app.listen(port, () => {
  console.log(`Example app listening at http://localhost:${port}`)
})

[bilics]

Is this possible? Also looking for this. Thanks!