UUID for lock ownership check

Closes TheDeveloper#3

lib/warlock.js

@@ -1,5 +1,6 @@
 var crypto       = require('crypto');
 var Scripty      = require('node-redis-scripty');
+var UUID         = require('uuid');
 
 var scripty;
 
@@ -9,7 +10,7 @@ module.exports = function(redis){
   scripty = new Scripty(redis);
 
   warlock.makeKey = function(key) {
-    return 'lock:' + crypto.createHash('md5').update(key).digest('hex').substr(0, 10);
+    return key + ':lock';
   };
 
   /**
@@ -23,33 +24,31 @@ module.exports = function(redis){
 
     if (typeof key !== 'string') return cb(new Error('lock key must be string'));
 
-    scripty.loadScriptFile('lock', __dirname + '/lua/lock.lua', function(err, lock){
+    var id;
+    UUID.v1(null, (id = new Buffer(16)));
+    id = id.toString('base64');
+    redis.set(warlock.makeKey(key), id, 'PX', ttl, 'NX', function(err, lockSet) {
       if (err) return cb(err);
 
-      var timestamp = Date.now();
-      lock.run(3, warlock.makeKey(key), ttl, timestamp, function(err, lockSet) {
-        if (err) return cb(err);
-
-        var unlock = warlock.unlock.bind(warlock, key, timestamp);
+      var unlock = warlock.unlock.bind(warlock, key, id);
 
-        if (!lockSet) unlock = false;
+      if (!lockSet) unlock = false;
 
-        return cb(err, unlock);
-      });
+      return cb(err, unlock);
     });
 
     return key;
   };
 
-  warlock.unlock = function(key, timestamp, cb) {
+  warlock.unlock = function(key, id, cb) {
     cb = cb || function(){};
 
     if (typeof key !== 'string') return cb(new Error('lock key must be string'));
 
     scripty.loadScriptFile('parityDel', __dirname + '/lua/parityDel.lua', function(err, parityDel){
       if (err) return cb(err);
 
-      return parityDel.run(2, warlock.makeKey(key), timestamp, cb);
+      return parityDel.run(2, warlock.makeKey(key), id, cb);
     });
   };