java - Enable HTTP2 with Tomcat in Spring Boot

Question

Tomcat 8.5, which will be the default in Spring Boot 1.4, supports HTTP/2.

How can HTTP/2 be enabled in a Spring Boot application?

question from:https://stackoverflow.com/questions/38612704/enable-http2-with-tomcat-in-spring-boot

Answer 1

You need to add the HTTP 2 upgrade protocol to Tomcat's connector. You can do that by customizing the embedded Tomcat container:

Java 8:

@Bean
public EmbeddedServletContainerCustomizer tomcatCustomizer() {
    return (container) -> {
        if (container instanceof TomcatEmbeddedServletContainerFactory) {
            ((TomcatEmbeddedServletContainerFactory) container)
                    .addConnectorCustomizers((connector) -> {
                connector.addUpgradeProtocol(new Http2Protocol());
            });
        }
    };
}

Java 7:

@Bean
public EmbeddedServletContainerCustomizer tomcatCustomizer() {
    return new EmbeddedServletContainerCustomizer() {

        @Override
        public void customize(ConfigurableEmbeddedServletContainer container) {
            if (container instanceof TomcatEmbeddedServletContainerFactory) {
                ((TomcatEmbeddedServletContainerFactory) container)
                        .addConnectorCustomizers(new TomcatConnectorCustomizer() {
                    @Override
                    public void customize(Connector connector) {
                        connector.addUpgradeProtocol(new Http2Protocol());
                    }

                });
            }
        }

    };
}