Adding connection validation and handling of PROTOCOL_CONNECTION_LOST errors

lib/dialects/mysql/connector-manager.js

@@ -19,7 +19,9 @@ module.exports = (function() {
     this.poolCfg = Utils._.defaults(this.config.pool, {
       maxConnections: 10,
       minConnections: 0,
-      maxIdleTime: 1000
+      maxIdleTime: 1000,
+      handleDisconnects: false,
+      validate: validateConnection
     });
     this.pendingQueries = 0;
     this.useReplicaton = !!config.replication;
@@ -83,6 +85,7 @@ module.exports = (function() {
           destroy: function(client) {
             disconnect.call(self, client)
           },
+          validate: self.poolCfg.validate,
           max: self.poolCfg.maxConnections,
           min: self.poolCfg.minConnections,
           idleTimeoutMillis: self.poolCfg.maxIdleTime
@@ -98,6 +101,7 @@ module.exports = (function() {
           destroy: function(client) {
             disconnect.call(self, client)
           },
+          validate: self.poolCfg.validate,
           max: self.poolCfg.maxConnections,
           min: self.poolCfg.minConnections,
           idleTimeoutMillis: self.poolCfg.maxIdleTime
@@ -115,6 +119,7 @@ module.exports = (function() {
         },
         max: self.poolCfg.maxConnections,
         min: self.poolCfg.minConnections,
+        validate: self.poolCfg.validate,
         idleTimeoutMillis: self.poolCfg.maxIdleTime
       })
     }
@@ -247,10 +252,25 @@ module.exports = (function() {
     connection.query("SET time_zone = '+0:00'");
     // client.setMaxListeners(self.maxConcurrentQueries)
     this.isConnecting = false
-
+    if (config.pool.handleDisconnects) {
+      handleDisconnect(this.pool, connection)
+    }
     done(null, connection)
   }
 
+  var handleDisconnect = function(pool, client) {
+    client.on('error', function(err) {
+      if (err.code !== 'PROTOCOL_CONNECTION_LOST') {
+        throw err
+      }
+      pool.destroy(client)
+    })
+  }
+
+  var validateConnection = function(client) {
+    return client && client.state != 'disconnected'
+  }
+
   var enqueue = function(queueItem, options) {
     options = options || {}
     if (this.activeQueue.length < this.maxConcurrentQueries) {
@@ -336,4 +356,4 @@ module.exports = (function() {
   }
 
   return ConnectorManager
-})()
\ No newline at end of file
+})()