HTTP 2.0 Server Demo

Spring Boot App with HTTP/2 enabled

HTTP Client

• OkHttp3 4.4.0: https://square.github.io/okhttp/
• httpcomponents-client-5: https://hc.apache.org/httpcomponents-client-5.0.x/index.html

User mkcert to produce pkcs12 keystore file

mkcert -pkcs12 localhost

HTTP/2 over TCP (h2c)

All four embedded web containers now support HTTP/2 over TCP (h2c) without any manual customization. To enable h2c, set server.http2.enabled is true and leave server.ssl.enabled set to false (its default value).

Caddy Server reverse_proxy configuration:

reverse_proxy {
    to http://127.0.0.1:2012
    transport http {
        versions h2c
    }
}

UDS support - Unix Domain Sockets

• Add dependency

       <dependency>
            <groupId>io.netty</groupId>
            <artifactId>netty-transport-native-kqueue</artifactId>
            <version>${netty.version}</version>
            <classifier>osx-x86_64</classifier>
        </dependency>

• Create NettyUdsConfig.java

import io.netty.channel.unix.DomainSocketAddress;
import org.springframework.boot.web.embedded.netty.NettyReactiveWebServerFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import java.util.Collections;

/**
 * Netty UDS configuration
 */
@Configuration
public class NettyUdsConfig {

    @Bean
    public NettyReactiveWebServerFactory factory() {
        NettyReactiveWebServerFactory factory = new NettyReactiveWebServerFactory();
        factory.setServerCustomizers(Collections.singletonList(httpServer -> httpServer.bindAddress(() -> new DomainSocketAddress("/tmp/test.sock"))));
        return factory;
    }
}

• Start server and test

curl -GET --unix-socket /tmp/test.sock http://localhost/

Reference

• Spring Boot SSL: https://docs.spring.io/spring-boot/docs/3.1.0/reference/html/features.html#features.ssl
• HTTP 2.0 specification: https://http2.github.io
• mkcert: https://github.com/FiloSottile/mkcert
• HttpCore 5.0 Examples: https://hc.apache.org/httpcomponents-core-5.0.x/examples.html
• HTTP/2 in Netty: https://www.baeldung.com/netty-http2
• How I can tell alias of the wanted key-entry to SSLSocket before connecting? https://stackoverflow.com/questions/15201251/how-i-can-tell-alias-of-the-wanted-key-entry-to-sslsocket-before-connecting
• tls demo: https://github.com/linux-china/tls-demo
• Spring SSL: https://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#howto.webserver.configure-ssl
• Three Ways to Run Your Java Locally with HTTPS: https://developer.okta.com/blog/2022/01/31/local-https-java