Accept wildcard anywhere in pool cluster pattern

closes #1570

Author: dougwilson

Changes.md

@@ -6,7 +6,8 @@ you spot any mistakes.
 
 ## HEAD
 
-* Accept regular expression as pool cluster pattern #1570 #1572
+* Accept regular expression as pool cluster pattern #1572
+* Accept wildcard anywhere in pool cluster pattern #1570
 * Add new error codes up to MySQL 5.7.17
 * Fix memory leak when using long-running domains #1619 #1620
 * Update `bignumber.js` to 3.1.2

Readme.md

@@ -468,7 +468,7 @@ poolCluster.on('remove', function (nodeId) {
   console.log('REMOVED NODE : ' + nodeId); // nodeId = SLAVE1
 });
 
-// A pattern can be passed with *  as wildcard at end of string
+// A pattern can be passed with *  as wildcard
 poolCluster.getConnection('SLAVE*', 'ORDER', function (err, connection) {});
 
 // The pattern can also be a regular expression

lib/PoolCluster.js

@@ -173,25 +173,12 @@ PoolCluster.prototype._findNodeIds = function _findNodeIds(pattern, includeOffli
   var foundNodeIds = this._findCaches[pattern];
 
   if (foundNodeIds === undefined) {
-    var nodeIds  = Object.keys(this._nodes);
+    var expression = patternRegExp(pattern);
+    var nodeIds    = Object.keys(this._nodes);
 
-    if (isRegExp(pattern)) {
-      foundNodeIds = nodeIds.filter(function (id) { return id.match(pattern); });
-    } else {
-      var wildcard = pattern.substr(-1) === '*';
-      var keyword  = wildcard
-        ? pattern.substr(0, pattern.length - 1)
-        : pattern;
-
-      if (wildcard) {
-        foundNodeIds = keyword.length !== 0
-          ? nodeIds.filter(function (id) { return id.substr(0, keyword.length) === keyword; })
-          : nodeIds;
-      } else {
-        var index = nodeIds.indexOf(keyword);
-        foundNodeIds = nodeIds.slice(index, index + 1);
-      }
-    }
+    foundNodeIds = nodeIds.filter(function (id) {
+      return id.match(expression);
+    });
 
     this._findCaches[pattern] = foundNodeIds;
   }
@@ -280,6 +267,18 @@ function isRegExp(val) {
     && Object.prototype.toString.call(val) === '[object RegExp]';
 }
 
+function patternRegExp(pattern) {
+  if (isRegExp(pattern)) {
+    return pattern;
+  }
+
+  var source = pattern
+    .replace(/([.+?^=!:${}()|\[\]\/\\])/g, '\\$1')
+    .replace(/\*/g, '.*');
+
+  return new RegExp('^' + source + '$');
+}
+
 function _cb(err) {
   if (err) {
     throw err;

test/unit/pool-cluster/test-internals.js

@@ -17,6 +17,8 @@ server.listen(common.fakeServerPort, function(err) {
 
   // _findNodeIds
   assert.deepEqual(cluster._findNodeIds('MASTER'), ['MASTER']);
+  assert.deepEqual(cluster._findNodeIds('MA*ER'), ['MASTER']);
+  assert.deepEqual(cluster._findNodeIds('*TER*'), ['CLUSTER::1', 'MASTER']);
   assert.deepEqual(cluster._findNodeIds('SLAVE*'), ['SLAVE1', 'SLAVE2']);
   assert.deepEqual(cluster._findNodeIds(/slave[1-2]/i), ['SLAVE1', 'SLAVE2']);