Helenus/Express Example

package.js

{
  "name": "test",
  "description": "An application to test helenus",
  "version": "0.0.1",
  "private": true,
  "dependencies": {
    "express": "3.x",
    "helenus": "0.6.x"
  }
}

perf.js

var helenus = require('helenus'),
    express = require('express'),
    util = require('util'),
    pool = new helenus.ConnectionPool({
        //hosts      : [], // removed on purpose
        keyspace   : 'nodejs',
        user       : 'nodejs',
        password   : 'nodejs',
        timeout    : 3000,
        hostPoolSize : 2,
    });

var cl = helenus.ConsistencyLevel.ONE;

pool.on('error', function(err){
   console.error(err.name, err.message);
});

pool.connect(function(err, keyspace) {
    if(err) {
        console.error(err);
    } else {
        console.log("connected");
    }
});

var app = express();

function buildResponse(res, body, status) {
   res.status(status);
   res.setHeader('Content-Type', 'text/plain');
   res.setHeader('Content-Length', Buffer.byteLength(body));
   res.end(body);
}

function printCQLErrors(err) {
    console.log("CQL Error: " + err);
}

app.use(function(req, res, next){
   var data = "";
   req.on('data', function(chunk){ data += chunk})
   req.on('end', function(){
      req.rawBody = data;
      next();
   })
})

app.get('/:key', function(req, res) {
    var query = "SELECT value FROM nodejs.test WHERE key = ?";
    pool.cql(query, [req.param('key')], { consistencyLevel: cl }, function(err, results) { 
        if(err) {
           printCQLErrors(err);
           buildResponse(res, "[cql error]", 500);
        } else {
            if(results.length > 0) {
               buildResponse(res, results[0].get('value').value, 200);
            } else {
               buildResponse(res, "[no value]", 404);
            }
        }
    });
});

app.post('/:key', function(req, res) {
    var query = "INSERT INTO nodejs.test (key, value) VALUES (?, ?)";
    pool.cql(query, [req.param('key'), req.rawBody], { consistencyLevel: cl }, function(err, results) { 
        if(err) {
           printCQLErrors(err);
           buildResponse(res, "[cql error]", 500);
        } else {
           buildResponse(res, "[success]", 200);
        }
    });
});

app.listen(8000);

schema.cql

CREATE KEYSPACE nodejs WITH replication = {'class': 'SimpleStrategy', 'replication_factor' : 3};

CREATE TABLE nodejs.test (
   key text PRIMARY KEY,
   value text
);

CREATE USER nodejs WITH PASSWORD 'nodejs';
GRANT ALL PERMISSIONS ON nodejs.test TO nodejs;