forward.js

const http = require("http");
const url = require('url');

// only http supported
const eth_node_url = "http://135.181.19.221:8545";

const forward_url = url.parse(eth_node_url);

var server = http.createServer((req, res) => {
  let input = [];
  req.on("data", (chunk) => {
    input.push(chunk);
  });

  req.on("end", () => {
    let body;
    try {
      body = JSON.parse(input);
      console.log("parsed JSON request successfully")
      body = JSON.stringify(body);
    } catch (exception) {
        console.log("can not parse JSON request", input.toString('utf8'));
    }

    const options = {
        protocol: forward_url.protocol,
        hostname: forward_url.hostname,
        port: forward_url.port || 80,
        path: forward_url.path,
        method: 'POST',
        headers: {
            'Content-Type': 'application/json',
            'Content-Length': body.length
        }
    };

    const req = http.request(options, (result) => {
        let output = '';
    
        result.on('data', (chunk) => {
            output += chunk;
        });
    
        result.on('end', () => {
            res.writeHead(200, {
                'Content-Type': 'application/json'
            });
            res.end(output.toString('utf8'));
            //console.log('delivered output successfully', output.toString('utf8'));
        });
    }).on("error", (err) => {
        console.log("Error: ", err.message);
    });

    req.write(body);
    req.end();  
    //console.log('forwarded input', body);   
  });
});

console.log("listening on port 7777");
server.listen(7777);