Merge pull request #22 from tobek/master

Adding 'has' function to check for existence of a server in the ring

README.md

@@ -208,6 +208,14 @@ Remove a server from the hash ring.
 
 ---
 
+#### HashRing.has(**server**)
+
+Checks if a given server exists in the hash ring.
+
+- **server** Server for whose existence we're checking.
+
+---
+
 #### HashRing.reset()
 
 Reset the HashRing and clean up it's references.

index.js

@@ -414,6 +414,19 @@ HashRing.prototype.remove = function remove(server) {
   return this.continuum();
 };
 
+/**
+ * Checks if a given server exists in the hash ring.
+ *
+ * @param {String} server Server for whose existence we're checking
+ * @api public
+ */
+HashRing.prototype.has = function add(server) {
+  for (var i = 0; i < this.ring.length; i++) {
+    if (this.ring[i].server === server) return true;
+  }
+  return false;
+};
+
 /**
  * Reset the HashRing to clean up all references
  *

tests/api.test.js

@@ -217,6 +217,28 @@ describe('HashRing', function () {
       });
     });
 
+    describe('#has', function () {
+      it('has a server', function () {
+        var ring = new Hashring([
+            '192.168.0.102:11212'
+          , '192.168.0.103:11212'
+          , '192.168.0.104:11212'
+        ]);
+
+        ring.has('192.168.0.102:11212').should.equal(true);
+      });
+
+      it('does not have a server', function () {
+        var ring = new Hashring([
+            '192.168.0.102:11212'
+          , '192.168.0.103:11212'
+          , '192.168.0.104:11212'
+        ]);
+
+        ring.has('192.168.0.105:11212').should.equal(false);
+      });
+    });
+
     describe('#range', function () {
       it('returns 20 servers', function () {
         var ring = new Hashring([