Connection configuration:

- Add ability to set channel class (enables use of, e.g., EpollEventLoop)
- Add option to set statement timeout in PostgreSQL

Author: erimatnor

db-async-common/src/main/scala/com/github/mauricio/async/db/Configuration.scala

@@ -19,6 +19,8 @@ package com.github.mauricio.async.db
 import java.nio.charset.Charset
 
 import io.netty.buffer.{ByteBufAllocator, PooledByteBufAllocator}
+import io.netty.channel.Channel
+import io.netty.channel.socket.nio.NioSocketChannel
 import io.netty.util.CharsetUtil
 
 import scala.concurrent.duration._
@@ -60,6 +62,8 @@ case class Configuration(username: String,
                          charset: Charset = Configuration.DefaultCharset,
                          maximumMessageSize: Int = 16777216,
                          allocator: ByteBufAllocator = PooledByteBufAllocator.DEFAULT,
+                         channelClass: Class[_ <: Channel] = classOf[NioSocketChannel],
+                         statementTimeout: Duration = 0.seconds,
                          connectTimeout: Duration = 5.seconds,
                          testTimeout: Duration = 5.seconds,
                          queryTimeout: Option[Duration] = None)

mysql-async/src/main/scala/com/github/mauricio/async/db/mysql/codec/MySQLConnectionHandler.scala

@@ -68,7 +68,7 @@ class MySQLConnectionHandler(
   private var currentContext: ChannelHandlerContext = null
 
   def connect: Future[MySQLConnectionHandler] = {
-    this.bootstrap.channel(classOf[NioSocketChannel])
+    this.bootstrap.channel(configuration.channelClass)
     this.bootstrap.handler(new ChannelInitializer[io.netty.channel.Channel]() {
 
       override def initChannel(channel: io.netty.channel.Channel): Unit = {

postgresql-async/src/main/scala/com/github/mauricio/async/db/postgresql/codec/PostgreSQLConnectionHandler.scala

@@ -81,7 +81,7 @@ class PostgreSQLConnectionHandler
 
   def connect: Future[PostgreSQLConnectionHandler] = {
     this.bootstrap.group(this.group)
-    this.bootstrap.channel(classOf[NioSocketChannel])
+    this.bootstrap.channel(configuration.channelClass)
     this.bootstrap.handler(new ChannelInitializer[channel.Channel]() {
 
       override def initChannel(ch: channel.Channel): Unit = {

postgresql-async/src/main/scala/com/github/mauricio/async/db/postgresql/pool/PostgreSQLConnectionFactory.scala

@@ -51,8 +51,8 @@ class PostgreSQLConnectionFactory(
 
   def create: PostgreSQLConnection = {
     val connection = new PostgreSQLConnection(configuration, group = group, executionContext = executionContext)
-    Await.result(connection.connect, configuration.connectTimeout)
-
+    val stmt = s"SET statement_timeout TO ${configuration.statementTimeout.toMillis};"
+    Await.result(connection.connect.map(conn => conn.sendQuery(stmt))(executionContext), configuration.connectTimeout)
     connection
   }