Latest Code

node_modules/strong-store-cluster/lib/worker/KeyLock.js

@@ -0,0 +1,56 @@
+
+module.exports = KeyLock;
+
+
+var request = require('./request.js');
+
+
+function KeyLock(collection, key, json) {
+  this._collection = collection;
+  this._key = key;
+  this._json = json;
+  this._updated = false;
+  this._released = false;
+}
+
+KeyLock.prototype.get = function() {
+  if (!this._json)
+    return undefined;
+  else
+    return JSON.parse(this._json);
+};
+
+KeyLock.prototype.set = function(newValue) {
+  if (this._released)
+    throw new Error("Can't set after releasing a lock.");
+
+  this._json = JSON.stringify(newValue);
+  this._updated = true;
+};
+
+KeyLock.prototype.del = function() {
+  if (this._released)
+    throw new Error("Can't delete after releasing a lock.");
+
+  this._json = undefined;
+  this._updated = true;
+};
+
+KeyLock.prototype.release = function(cb) {
+  if (this._released)
+    throw new Error('KeyLock has already been released.');
+
+  this._released = true;
+
+  if (!this._updated)
+    this._collection._request('release', this._key, null, cb && afterRelease);
+  else
+    this._collection._request('setRelease',
+                              this._key,
+                              { json: this._json },
+                              cb && afterRelease);
+
+  function afterRelease(err, msg) {
+    return cb(err);
+  }
+};