How to "pass forward" a post() req to another api , get the res and send it back?

Question

Background: I am using building a system which uses 2 different 3rd parties to do something. 3rd party #1 - is facebook messenger app, which requires a webhook to connect and send info via POST() protocol. 3rd party #2 - is a platform which I used to build a bot (called GUPSHUP).

My server is in the middle between them - so, I need to hook the facebook messenger app to my endpoint on MY server (already did), so every message that the Facebook app get's, it sends to MY server.

Now, what I actually need, is that my server to act as "middleware" and simply send the "req" and "res" it gets to the other platform url (let's call it GUPSHUP-URL), get the res back and send it to the Facebook app.

I am not sure how to write such a middleware that acts like this. My server post function is:

    app.post('/webhook', function (req, res) {
/* send to the GUPSHUP-URL , the req,res which I got ,
   and get the update(?) req and also res so I can pass them
   back like this (I think) 
   req = GUPSHUP-URL.req
   res = GUPSHUP-URL.res
   
*/

});

Answer 1

Yes , you can pass do request on another server using request module

var request = require('request');

app.post('/webhook', function (req, res) {
    /* send to the GUPSHUP-URL , the req,res which I got ,
       and get the update(?) req and also res so I can pass them
       back like this (I think) 
       req = GUPSHUP-URL.req
       res = GUPSHUP-URL.res

       */

       request('GUPSHUP-URL', function (error, response, body) {
        if(error){

             console.log('error:', error); // Print the error if one occurred 
             return res.status(400).send(error)
           }
            console.log('statusCode:', response && response.statusCode); // Print the response status code if a response was received 

              console.log('body:', body); // Print the HTML for the Google homepage. 
              return res.status(200).send(body); //Return to client
            });

     });

2nd Version

var request = require('request');


//use callback function to pass uper post
function requestToGUPSHUP(url,callback){

 request(url, function (error, response, body) {

  return callback(error, response, body);
}

app.post('/webhook', function (req, res) {
    /* send to the GUPSHUP-URL , the req,res which I got ,
       and get the update(?) req and also res so I can pass them
       back like this (I think) 
       req = GUPSHUP-URL.req
       res = GUPSHUP-URL.res

       */

       requestToGUPSHUP('GUPSHUP-URL',function (error, response, body) {

        if(error){

          return res.status(400).send(error)
        }

          //do whatever you want


          return res.status(200).send(body); //Return to client
        });


     });

More info Request module