strong-tunnel

Easy tunnelling over ssh2.

Usage

There is nothing to configure, but some environment variables are used to set defaults if no options are given.

var st = require('strong-tunnel');

st(someUrl, sshOpts, function(err, url) {
  // if someUrl was plain http, url will be someUrl
  // if someUrl was http+ssh://, url points to a local ephemeral tunnel
  // sshOpts is optional with defaults described below.
  http.get(url, onResponse);
});

Username

Your current local username is assumed to be the username used for ssh. To override this you can set the LOGNAME environment variable to the desired username before the tunnel URL is created.

Credentials

To keep the API simple, it is assumed that an ssh agent is already running, that the path to its domain socket is in the SSH_AUTH_SOCK environment variable, and that an appropriate private key has been loaded into that agent.

This is usually done for you in modern *nix environments as part of your login shell/session. See ssh-agent(1) for more information about ssh agents.

Longer Example

var fmt = require('util').format;
var fs = require('fs');
var http = require('http');
var st = require('strong-tunnel');

var server = http.createServer(function(req, res) {
  res.end(JSON.stringify(req.headers));
});

var sshOpts = {
  host: '127.0.0.1',
};

// The following are not required and if they aren't set here or in the ENV,
// strong-tunnel will use logical default values.
sshOpts.port = process.env.SSH_PORT;
sshOpts.username = process.env.SSH_USERNAME;
if (process.env.SSH_PRIVATE_KEY) {
  sshOpts.privateKey = fs.readFileSync(process.env.SSH_PRIVATE_KEY, 'utf8');
}

server.listen(0, '127.0.0.1', function() {
  var httpPort = this.address().port;
  var direct = fmt('http://127.0.0.1:%d/', httpPort);
  var tunneled = fmt('http+ssh://127.0.0.1:%d/', httpPort);

  // Standard request using URL string
  http.get(direct, resLog('%s using %s:', direct, direct));

  // URL is only modified if a tunneling URL was given
  st(direct, function(err, url) {
    if (err) throw err;
    // url == direct, unmodified
    http.get(url, resLog('%s using %s:', direct, url));
  });

  // optional second argument containing ssh config
  st(tunneled, sshOpts, function(err, url) {
    if (err) throw err;
    // url != tunneled, is modified
    http.get(url, resLog('%s using %s:', tunneled, url));
  });

  server.unref();
});

function resLog(prefix) {
  prefix = fmt.apply(null, arguments);
  return function onResponse(res) {
    res.on('data', function(d) {
      console.log('%s -> %s', prefix, d);
    });
  };
}