vertx-mysql-postgresql-client The pool returns an invalid connection after client idle for a while

I'm using vertx-mysql-postgresql-client version 3.8.3.

My client works fine in the beginning. But when the client keeps idle for a while, I obtain an invalid connection from the client.

AIK, Mysql server will close those long idle connections by force. So I guess the client returned a cached connection which is actually invalid since it was already reset by the server. Any query on that connection will raise an exception. Just try getConnection again, a new connection is returned successfully.

Is there any built-in tech to overcome this issue? or, should I handle such exeception on my own?

I post my conf and code below. Did I miss something?

I configured my client as below:

        JsonObject dbConfig = new JsonObject();
        dbConfig.put("host", "xxxx");
        dbConfig.put("port", 3306);
        dbConfig.put("maxPoolSize", 5);
        dbConfig.put("username", "xxxx");
        dbConfig.put("password", "xxxx");
        dbConfig.put("database", "xxxx");
        dbConfig.put("maxConnectionRetries", 10);
        dbConfig.put("connectionRetryDelay", 500);
        dbPool = MySQLClient.createShared(vertx, dbConfig, "mysql-connection-pool");

and query data like this:

    public void execute(String sql, JsonArray params, Handler<AsyncResult<JsonObject>> handler) {
        dbPool.getConnection(res -> {
            if (res.succeeded()) {
                SQLConnection connection = res.result();
                log.debug("connection: {} sql: {}, params: {}", connection, sql, params);
                connection.queryWithParams(sql, params, qryRes -> { // Here I got an exception!
                    if (qryRes.succeeded()) {
                        ResultSet resultSet = qryRes.result();
                        log.info(resultSet.getRows().toString());
                        handler.handle(Future.succeededFuture(new JsonObject().put("data", resultSet.getRows())));
                    } else {
                         handler.handle(Future.failedFuture(qryRes.cause().getMessage()));
                    }
                    connection.close();
                });
            } else {
                handler.handle(Future.failedFuture(res.cause().getMessage()));
            }
        });
    }

Oct 21 '19 07:10 Nossiac

Just reproduce it, here's the exception log.

java.io.IOException: 远程主机强迫关闭了一个现有的连接。 , the chinese part means "the remote server has reset an existing connection by force".

2019-10-21 15:39:26,082 [vert.x-eventloop-thread-1] DEBUG c.n.j.j.database.DatabaseServiceImpl - connection: io.vertx.ext.asyncsql.impl.MySQLConnectionImpl@46944971 sql: SELECT t_user.id, t_user.username WHERE t_user.id = ? , params: [5240098559942534998]
2019-10-21 15:39:45,291 [vert.x-eventloop-thread-6] ERROR c.g.m.async.db.mysql.MySQLConnection - Transport failure 
java.io.IOException: 远程主机强迫关闭了一个现有的连接。
	at java.base/sun.nio.ch.SocketDispatcher.read0(Native Method)
	at java.base/sun.nio.ch.SocketDispatcher.read(SocketDispatcher.java:43)
	at java.base/sun.nio.ch.IOUtil.readIntoNativeBuffer(IOUtil.java:276)
	at java.base/sun.nio.ch.IOUtil.read(IOUtil.java:233)
	at java.base/sun.nio.ch.IOUtil.read(IOUtil.java:223)
	at java.base/sun.nio.ch.SocketChannelImpl.read(SocketChannelImpl.java:358)
	at io.netty.buffer.UnpooledDirectByteBuf.setBytes(UnpooledDirectByteBuf.java:587)
	at io.netty.buffer.AbstractByteBuf.writeBytes(AbstractByteBuf.java:1140)
	at io.netty.buffer.SwappedByteBuf.writeBytes(SwappedByteBuf.java:828)
	at io.netty.channel.socket.nio.NioSocketChannel.doReadBytes(NioSocketChannel.java:347)
	at io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:148)
	at io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:697)
	at io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:632)
	at io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:549)
	at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:511)
	at io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:918)
	at io.netty.util.internal.ThreadExecutorMap$2.run(ThreadExecutorMap.java:74)
	at io.netty.util.concurrent.FastThreadLocalRunnable.run(FastThreadLocalRunnable.java:30)
	at java.base/java.lang.Thread.run(Thread.java:835)
2019-10-21 15:39:45,297 [vert.x-eventloop-thread-6] DEBUG [connection-handler][mysql-connection-1] - Channel became inactive
2019-10-21 15:39:45,297 [vert.x-eventloop-thread-1] ERROR c.n.j.j.database.DatabaseServiceImpl - 远程主机强迫关闭了一个现有的连接。

Oct 21 '19 07:10 Nossiac

Do we have any fix on this, pro?