Spring Boot SSL (HTTPS) Configuration

To enable SSL or HTTPS for Spring Boot web application, puts the certificate file .p12 or .jks in the resources folder, and declares the server.ssl.* values in the application.properties

Self-signed Certificate

For this example, we will use the JDK’s keytool to generate a self-sign certificate in PKCS12 format. The below command will create a PKCS12 cert, name nagaraju.p12, puts this file into the resources folder.

Terminal

$ keytool -genkeypair -keyalg RSA -keysize 2048 -storetype PKCS12 -keystore nagaraju.p12 -validity 365

Enter keystore password:  
Re-enter new password:




application.properties

# SSL
server.port=8443
server.ssl.key-store=classpath:nagaraju.p12
server.ssl.key-store-password=123456

# JKS or PKCS12
server.ssl.keyStoreType=PKCS12

# Spring Security
# security.require-ssl=true
Copy

Done, starts the Spring Boot, and access https://localhost:8443

Redirect all traffic from port 8080 to 8443.

StartApplication.java

package com.muthyatechnology.config
import org.apache.catalina.Context;
import org.apache.catalina.connector.Connector;
import org.apache.tomcat.util.descriptor.web.SecurityCollection;
import org.apache.tomcat.util.descriptor.web.SecurityConstraint;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory;
import org.springframework.boot.web.servlet.server.ServletWebServerFactory;
import org.springframework.context.annotation.Bean;

@SpringBootApplication
public class StartApplication {
    public static void main(String[] args) {
        SpringApplication.run(StartApplication.class, args);
    }

    // spring boot 2.x
    @Bean
    public ServletWebServerFactory servletContainer() {
        TomcatServletWebServerFactory tomcat = new TomcatServletWebServerFactory() {
            @Override
            protected void postProcessContext(Context context) {
                SecurityConstraint securityConstraint = new SecurityConstraint();
                securityConstraint.setUserConstraint("CONFIDENTIAL");
                SecurityCollection collection = new SecurityCollection();
                collection.addPattern("/*");
                securityConstraint.addCollection(collection);
                context.addConstraint(securityConstraint);
            }
        };
        tomcat.addAdditionalTomcatConnectors(redirectConnector());
        return tomcat;
    }

    private Connector redirectConnector() {
        Connector connector = new Connector("org.apache.coyote.http11.Http11NioProtocol");
        connector.setScheme("http");
        connector.setPort(8080);
        connector.setSecure(false);
        connector.setRedirectPort(8443);
        return connector;
    }

}