env.sh

# local env.
$ export COUCH_HOST=https://xxx.couchdb.com
$ export COUCH_PORT=xxx
$ export COUCH_USERNAME=xxx
$ export COUCH_PASSWORD=xxx
$ export COUCH_DATABASE=xxx

# cloud env.
$ heroku config:add COUCH_HOST=https://xxx.couchdb.com
$ heroku config:add COUCH_PORT=xxx
$ heroku config:add COUCH_USERNAME=xxx
$ heroku config:add COUCH_PASSWORD=xxx
$ heroku config:add COUCH_DATABASE=xxx

server.js

var http      = require('http'),
    form2json = require('form2json'),
    cradle    = require('cradle');

cradle.setup({
    host: process.env.COUCH_HOST,
    port: process.env.COUCH_PORT,
    cache: true, 
    raw: false
});

var adminConnection = new(cradle.Connection) (
  process.env.COUCH_HOST,
  process.env.COUCH_PORT,
  {
      auth: {
          username: process.env.COUCH_USERNAME,
          password: process.env.COUCH_PASSWORD
      }
  }
);

http.createServer(function (req, res) {
  var fullBody = '';
  req.on('data', function(chunk) {
      // append the current chunk of data to the fullBody variable
      fullBody += chunk.toString();
  });
  req.on('end', function() {
    var jsonBody = form2json.decode(fullBody);
    var payload = JSON.parse(jsonBody.payload);
    payload.type = jsonBody.type;

    var vendDB = adminConnection.database(process.env.COUCH_DATABASE);
    vendDB.merge(
        payload.id,
        payload,
        function (err, res) {
          if (err) {
            console.log('No previous entry, adding...');
            //console.error(err);
            vendDB.save(
              payload.id,
              payload,
              function (err, res) {
                if (err) {
                  console.log('Failed to save...');
                  console.error(err);
                } else {
                  console.log('Added!');
                  console.log(res);
                }
              }
            );
          } else {
            console.log('Found previous entry, updating...');
            console.log(res);
          }
        }
    );

    res.writeHead(200, "OK", {'Content-Type': 'text/html'});
    res.end();
  });
  req.on('error', function(e) {
    console.log('problem with request: ' + e.message);
  });
}).listen(8080);