Building Basic Netty Client

Hello, I'm working on a mod that communicates information about the minecraft server to outside sources. One of the ways I'm trying to accomplish this is by hooking into certain events and sending out an HTTP post request with a json payload to a user-defined endpoint. I'm using Netty to accomplish this, since it's already used by minecraft. For some reason, though, my HttpClient won't send the messages through. I have print statements before and after message sending and it gets to the first message, but never gets to the second one. I realize this is more of a question about Netty than forge but the Netty community doesn't seem to be very active and I haven't gotten a response yet. I'm hoping that someone here will  be able to help me with this issue.

Below, you can find my code:

package com.anzanama.statusapi.http.client;

import io.netty.bootstrap.Bootstrap;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.SocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.http.*;
import io.netty.util.CharsetUtil;

public class HttpClient {
    private String uri;
    private int port;
    private String payload;

    public HttpClient(String uri, int port, String payload) {
        this.uri = uri;
        this.port = port;
        this.payload = payload;
    }

    public void run() throws Exception {
        EventLoopGroup workerGroup = new NioEventLoopGroup();

        try {
            Bootstrap b = new Bootstrap();
            b.group(workerGroup);
            b.channel(NioSocketChannel.class);
            //b.option(ChannelOption.SO_KEEPALIVE, true);
            b.handler(new ChannelInitializer<SocketChannel>() {
                @Override
                public void initChannel(SocketChannel ch) throws Exception {
                    ch.pipeline().addLast(new HttpClientCodec());
                    ch.pipeline().addLast(new HttpObjectAggregator(1048576));
                    ch.pipeline().addLast(new HttpClientHandler());
                    ch.pipeline().addLast(new HttpRequestEncoder());
                }
            });

            HttpRequest request = HttpRequester.createRequest(this.uri, this.payload);
            request.headers().set(HttpHeaderNames.CONTENT_TYPE, "application/json");
            System.out.println("Sending message!");
            Channel f = b.connect(uri, port).channel();
            f.writeAndFlush(request);
            f.closeFuture().sync();
            System.out.println("Message was sent!");
        } finally {
            workerGroup.shutdownGracefully();
        }
    }
}

package com.anzanama.statusapi.http.client;

import io.netty.handler.codec.http.*;

import static io.netty.buffer.Unpooled.copiedBuffer;

public class HttpRequester {
    public static FullHttpRequest createRequest(String uri, String payload) {
        return createRequest(uri, payload.getBytes());
    }

    public static FullHttpRequest createRequest(String uri, byte[] payload) {
        return createRequest(uri, payload, HttpVersion.HTTP_1_1);
    }

    public static FullHttpRequest createRequest(String uri, byte[] payload, final HttpVersion version) {
        if (0 < payload.length)
        {
            FullHttpRequest request = new DefaultFullHttpRequest(version, HttpMethod.POST, uri, copiedBuffer(payload));
            request.headers().set(HttpHeaderNames.CONTENT_LENGTH, payload.length);
            return request;
        }
        else
        {
            return new DefaultFullHttpRequest(version, HttpMethod.POST, uri);
        }
    }
}