[WIP] Modify mysql driver to reconnect after timeout

lib/drivers/mysql.js

@@ -4,33 +4,62 @@ module.exports = function MysqlDriver() {
 
   return {
     connect: function connect(opts, callback) {
-      const conn = mysql.createConnection(opts)
-      conn.connect(callback)
-      return conn
+      if (callback) {
+        process.nextTick(function () {
+          callback(null)
+        })
+      }
+
+      opts.connectionLimit = 100
+      return mysql.createPool(opts)
     },
-    close: function close(connection, callback) {
-      return connection.end(callback)
+    close: function close(pool, callback) {
+      pool.end(callback)
     },
-    getQueryFn: function getQueryFn(connection) {
+    getQueryFn: function getQueryFn(pool) {
       return function (sql, params, callback) {
         const opts = { sql: sql }
-        return connection.query(opts, params, callback)
+
+        pool.getConnection(function (err, connection) {
+          if (err) {
+            if (callback) 
+              return callback(err)
+            else
+              return console.error(err)
+          }
+
+          return connection.query(opts, params, function (err, rows) {
+            connection.release()
+            if (callback) callback(err, rows)
+          })
+        })
       }
     },
-    getStreamFn: function getStreamFn(connection) {
+    getStreamFn: function getStreamFn(pool) {
       // will be in the context of `db`
       // expected to return a stream
       return function streamQuery(sql, opts) {
         const stream = new Stream()
-        const queryStream = this.query(sql)
         const handlers = this.driver.streamHandlers(stream, opts)
 
-        stream.pause = connection.pause.bind(connection)
-        stream.resume = connection.resume.bind(connection)
+        pool.getConnection(function (err, connection) {
+          if (err) return stream.emit('error', err)
+
+          function endCallback(err) {
+            connection.release()
+            handlers.done(err)
+          }
+
+          const queryStream = connection.query(sql)
+
+          stream.pause = connection.pause.bind(connection)
+          stream.resume = connection.resume.bind(connection)
+
+          queryStream.on('result', handlers.row)
+          queryStream.on('end', endCallback)
+          queryStream.on('error', stream.emit.bind(stream, 'error'))
+        })
 
-        queryStream.on('result', handlers.row)
-        queryStream.on('end', handlers.done)
-        queryStream.on('error', stream.emit.bind(stream, 'error'))
         return stream
       }
     },