HTTP Proxy Server

This is a small tool developed using Node native modules only (no dependencies) that connects to a TLS-based JSON-RPC server that does not serve a HTTP interface (e.g. ElectrumX) and provides a local HTTP interface you can send your requests to.

For the sake of concurrency, the remote JSON-RPC server must implement the message ID handling (request's and response's "id" property).

This is a command line tool. Not intended to be used as NodeJS library.

How to install

Download this repo and just use the tlsjsonproxy.js file in command line.

For a global install, run npm i -g tlsjsonproxy and use the "tlsjsonproxy" command instead.

How to use

First, try connecting to the remote server to check if it's up. Example:

openssl s_client -connect fortress.qtornado.com:50002

Try pasting a command, e.g.:

{ "method" : "blockchain.block.header", "params": [ 1], "id": "msg_id"}

If everything is all ok, you'll get something like:

{"jsonrpc": "2.0", "result": "010000006fe28c0ab6f1b372c1a6a246ae63f74f931e8365e15a089c68d6190000000000982051fd1e4ba744bbbe680e1fee14677ba1a3c3540bf7b1cdb606e857233e0e61bc6649ffff001d01e36299", "id": "msg_id"}

Now close the connection (Ctrl + C) and let's set up this script to allow us to perform the same request through a HTTP API. The usage is:

node tlsjsonproxy.js <remote server> <remote port> <local port> [<local server=0.0.0.0>]

• Remote server: the server to connect to
• Remote port: the port in the remote server
• Local port: local port in your machine where the HTTP server will listen at
• Local server (optional): the local network interface (0.0.0.0 for all, 127.0.0.1 to accept loopback connections only or the interface's IP address)

Example:

node tlsjsonproxy.js fortress.qtornado.com 50002 8080

Now you can perform the same request we did before, but using HTTP.

Note: the examples below were generated by Insomnia

Example with cURL command:

curl --request POST \
  --url http://localhost:8081/ \
  --header 'content-type: application/json' \
  --data '{ "method" : "blockchain.block.header", "params": [ 1]}'

Example with Javascript's fetch:

fetch("http://localhost:8081/", {
  "method": "POST",
  "headers": {
    "content-type": "application/json"
  },
  "body": {
    "method": "blockchain.block.header",
    "params": [
      1
    ]
  }
})
.then(response => {
  console.log(response);
})
.catch(err => {
  console.log(err);
});

Example with PHP cURL:

<?php

$curl = curl_init();

curl_setopt_array($curl, array(
  CURLOPT_PORT => "8081",
  CURLOPT_URL => "http://localhost:8081/",
  CURLOPT_RETURNTRANSFER => true,
  CURLOPT_ENCODING => "",
  CURLOPT_MAXREDIRS => 10,
  CURLOPT_TIMEOUT => 30,
  CURLOPT_HTTP_VERSION => CURL_HTTP_VERSION_1_1,
  CURLOPT_CUSTOMREQUEST => "POST",
  CURLOPT_POSTFIELDS => "{ \"method\" : \"blockchain.block.header\", \"params\": [ 1]}",
  CURLOPT_HTTPHEADER => array(
    "content-type: application/json"
  ),
));

$response = curl_exec($curl);
$err = curl_error($curl);

curl_close($curl);

if ($err) {
  echo "cURL Error #:" . $err;
} else {
  echo $response;
}