Merge pull request #284 from kcarlson/aws-auto-discovery

Support for 'config get cluster'

Author: Ron Korving

lib/memcached.js

@@ -122,7 +122,7 @@ Client.config = {
     if(!server.match(/(.+):(\d+)$/)) {
         server = server + ':11211';
     }
-    
+
     // server is dead, bail out
     if (server in this.issues && this.issues[server].failed) {
         return callback(false, false);
@@ -565,6 +565,11 @@ Client.config = {
 
       return [BUFFER, false];
     }
+    // Amazon-specific memcached configuration information, used for node
+    // auto-discovery.
+  , 'CONFIG': function() {
+      return [CONTINUE, this.bufferArray[0]];
+    }
   };
 
   function resultSetIsEmpty(resultSet) {
@@ -706,9 +711,21 @@ Client.config = {
       token = S.bufferArray.shift();
       tokenSet = token.split(' ');
 
-      // special case for digit only's these are responses from INCR and DECR
-      if (/^\d+$/.test(tokenSet[0])) tokenSet.unshift('INCRDECR');
-
+      if (/^\d+$/.test(tokenSet[0])) {
+          // special case for "config get cluster"
+          // Amazon-specific memcached configuration information, see aws
+          // documentation regarding adding auto-discovery to your client library.
+          // Example response of a cache cluster containing three nodes:
+          //   configversion\n
+          //   hostname|ip-address|port hostname|ip-address|port hostname|ip-address|port\n\r\n
+          if (/(([-.a-zA-Z0-9]+)\|(\b\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}\b)\|(\d+))/.test(S.bufferArray[0])) {
+              tokenSet.unshift('CONFIG');
+          }
+          // special case for digit only's these are responses from INCR and DECR
+          else {
+            tokenSet.unshift('INCRDECR');
+          }
+      }
       // special case for value, it's required that it has a second response!
       // add the token back, and wait for the next response, we might be
       // handling a big ass response here.