Add option to expire

.gitignore

@@ -1,7 +1,7 @@
 # Logs
 logs
 *.log
-
+*.DS_Store
 # Runtime data
 pids
 *.pid

src/index.js

@@ -34,6 +34,13 @@ module.exports = function(config) {
  * @param {String} namespace The namespace to use for storing in Redis
  * @returns {{get: get, save: save, all: all, allById: allById}}
  */
+function isInt(n) {
+    if (isNaN(n) | n === 0) {
+        return false;
+    }
+    return (typeof x === 'number') && ( x % 1 === 0);
+}
+
 function getStorageObj(client, namespace) {
     return {
         get: function(id, cb) {
@@ -47,6 +54,15 @@ function getStorageObj(client, namespace) {
             }
 
             client.hset(namespace, object.id, JSON.stringify(object), cb);
+
+            if (object.expire) {
+                // check for integer
+                if (!isInt(object.expire)) {
+                    return cb(new Error('The \"expire\" property must be a positive integer', {}));
+                } else {
+                    client.EXPIRE(namespace, parseInt(object.expire));
+                }
+            }
         },
         remove: function(id, cb) {
             client.hdel(namespace, [id], cb);