Error handler for connection implemented

#2

Author: numtel

README.md

@@ -37,11 +37,15 @@ This package has been tested to work in MySQL 5.5.40 and 5.6.19. Expected suppor
 
 The `LiveMysql` constructor makes 3 connections to your MySQL database:
 
-* Connection for executing `SELECT` queries (exposed on instance as `db` property)
+* Connection for executing `SELECT` queries (exposed `node-mysql` instance as `db` property)
 * Replication slave connection
 * `information_schema` connection for column information
 
-One argument, an object defining the settings. In addition to the [`node-mysql` connection settings](https://github.com/felixge/node-mysql#connection-options), the following settings are available:
+
+Argument | Type | Description
+---------|------|---------------------------
+`settings` | `object` | An object defining the settings. In addition to the [`node-mysql` connection settings](https://github.com/felixge/node-mysql#connection-options), the additional settings below are available.
+`callback` | `function` | Optional callback on connection success/failure. Accepts one argument, `error`.
 
 Setting | Type | Description
 --------|------|------------------------------

lib/LiveMysql.js

@@ -5,13 +5,12 @@ var mysql = require('mysql');
 
 var LiveMysqlSelect = require('./LiveMysqlSelect');
 
-function LiveMysql(settings){
+function LiveMysql(settings, callback){
   var self = this;
-  var zongji = new ZongJi(settings);
   var db = mysql.createConnection(settings);
 
   self.settings = settings;
-  self.zongji = zongji;
+  self.zongji = null;
   self.db = db;
   self._select = [];
   // Cache query results for any new, duplicate SELECT statements
@@ -24,42 +23,47 @@ function LiveMysql(settings){
     includeSchema: {}
   };
 
-  db.connect();
+  db.connect(function(error){
+    if(error && callback) return callback(error);
 
-  zongji.on('binlog', function(event) {
-    if(event.getEventName() === 'tablemap') return;
-    if(self._select.length === 0) return;
+    var zongji = self.zongji = new ZongJi(settings);
 
-    // Cache query results within this update event
-    var eventResults = {};
+    zongji.on('binlog', function(event) {
+      if(event.getEventName() === 'tablemap') return;
+      if(self._select.length === 0) return;
 
-    function _nextSelect(index){
-      var select;
-      if(index < self._select.length){
-        select = self._select[index];
-        if(select.matchRowEvent(event)){
-          if(select.query in eventResults){
-            select._setRows(eventResults[select.query]);
-            _nextSelect(index + 1);
-          }else{
-            select.update(function(error, rows){
-              if(error === undefined){
-                eventResults[select.query] = rows;
-              }
+      // Cache query results within this update event
+      var eventResults = {};
+
+      function _nextSelect(index){
+        var select;
+        if(index < self._select.length){
+          select = self._select[index];
+          if(select.matchRowEvent(event)){
+            if(select.query in eventResults){
+              select._setRows(eventResults[select.query]);
               _nextSelect(index + 1);
-            });
+            }else{
+              select.update(function(error, rows){
+                if(error === undefined){
+                  eventResults[select.query] = rows;
+                }
+                _nextSelect(index + 1);
+              });
+            }
+          }else{
+            _nextSelect(index + 1);
           }
-        }else{
-          _nextSelect(index + 1);
         }
       }
-    }
 
-    _nextSelect(0);
+      _nextSelect(0);
 
-  });
+    });
 
-  zongji.start(self.zongjiSettings);
+    zongji.start(self.zongjiSettings);
+    if(callback) return callback();
+  });
 }
 
 LiveMysql.prototype.select = function(query, triggers){

package.json

@@ -1,6 +1,6 @@
 {
   "name": "mysql-live-select",
-  "version": "0.0.13",
+  "version": "0.0.14",
   "description": "Live updating MySQL SELECT statements",
   "main": "lib/LiveMysql.js",
   "repository": "https://github.com/numtel/mysql-live-select",

test/index.js

@@ -176,7 +176,17 @@ module.exports = {
       });
     });
   },
-
+  error_invalid_connection: function(test){
+    var myTest = new LiveMysql({
+      host: '127.0.0.1',
+      port: 12345,
+      user: 'not-working',
+      password: 'hahhaha'
+    }, function(error){
+      test.equal(error.code, 'ECONNREFUSED');
+      test.done();
+    });
+  },
   error_no_db_selected: function(test){
     server.on('ready', function(conn, esc, escId, queries){