node-async-redis.js

var http = require("http"),
    redis = require("redis");

var redisClient = redis.createClient(6379, "127.0.0.1", {});
var TTL = 300;

var server = http.createServer(function(request, response) {
  var headers = {"Content-Type": "text/plain"};
  if (request.method.toUpperCase() !== "POST") {
    response.writeHead(405, headers);
    response.end("Only POST requests are allowed!");
  } else {
    processBody(request, function(err, body) {
      if (err != null) {
        response.writeHead(err.code, headers);
        response.end(err.msg);
      } else {
        redisClient.set(JSON.stringify(body), "1", "NX", "EX", TTL, function(err, reply) {
          var status = 500;
          if (err === null) {
            if (reply === null) {
              status = 200;
            } else if (reply === "OK") {
              status = 201;
            }
          }
          response.writeHead(status, headers);
          response.end();
        });
      }
    });
  }
}).listen(9000);

function processBody(request, callback) {
  var strBody = "";
  request.on("data", function(data) {
    strBody += data;
    if(strBody.length > 1e6)
      callback({code: 413, msg: "Too much data."});
    });
  request.on("end", function() {
    try {
      var body = JSON.parse(strBody);
      callback(null, body);
    } catch (err) {
      callback({code: 400, msg: "Body is not a valid JSON object."});
    }
  });
};