added memcached kvstore backend

lib/config.js

@@ -6,7 +6,7 @@ const fs = require('fs');
 const url = require('url');
 const convict = require('convict');
 
-const AVAILABLE_BACKENDS = ["memory", "mysql"];
+const AVAILABLE_BACKENDS = ["memory", "mysql", "memcached"];
 
 
 var conf = module.exports = convict({
@@ -36,6 +36,14 @@ var conf = module.exports = convict({
       default: AVAILABLE_BACKENDS
     }
   },
+  memcached: {
+    hosts: {
+      default: '127.0.0.1:11211'
+    },
+    lifetime: {
+      default: 1000 * 60 * 2
+    }
+  },
   mysql: {
     user: {
       default: 'root',

lib/kvstore/memcached.js

@@ -0,0 +1,81 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+const Hapi = require('hapi');
+const config = require('../config');
+const kvstore = require('../kvstore');
+const Memcached = require('memcached');
+
+var client;
+var lifetime = 0;
+
+function get(key, cb) {
+  client.gets(key,
+    function (err, result) {
+      if (err) { cb(err); }
+      else if (!result) { cb(null, null); }
+      else {
+        cb(null,
+          {
+            value: result[key],
+            casid: +(result.cas)
+          }
+        );
+      }
+    }
+  );
+}
+
+function set(key, value, cb) {
+  client.set(key, value, lifetime,
+    function (err, result) {
+      if (err) { cb(err); }
+      else if (!result) { cb('NOT SET'); }
+      else { cb(null); }
+    }
+  );
+}
+
+function cas(key, value, casid, cb) {
+  client.cas(key, value, casid, lifetime,
+    function (err, result) {
+      if (err) { cb(err); }
+      else if (!result) { cb(kvstore.ERROR_CAS_MISMATCH); }
+      else { cb(null); }
+    }
+  );
+}
+
+function del(key, cb) {
+  client.del(
+    key,
+    function (err) {
+      cb(err);
+    }
+  );
+}
+
+
+module.exports = {
+  connect: function (options, callback) {
+    if (!client) {
+      options = Hapi.utils.merge(options, config.get('memcached'));
+      client = new Memcached(options.hosts, options);
+      lifetime = options.lifetime;
+    }
+    var api = {
+      get: get,
+      set: set,
+      cas: cas,
+      delete: del
+    };
+    callback(null, api);
+  },
+  close: function (cb) {
+    if (client) {
+      client.end();
+    }
+    if (cb) { cb(); }
+  }
+};

package.json

@@ -17,6 +17,7 @@
     "node": "0.10.x"
   },
   "dependencies": {
+    "memcached": "0.2.2",
     "hapi": "1.1.0",
     "compute-cluster": "0.0.7",
     "jwcrypto": "0.4.3",

server.js

@@ -30,5 +30,8 @@ server.ext(
 	}
 );
 
+//TODO throttle extension
+//TODO toobusy extension
+
 module.exports = server;