[FIXED] Using multiple dispatcher servlets / web contexts with spring boot

Issue

I created a spring boot application with a parent context (services) and child context (spring-webmvc controllers):

@Configuration
public class MainApiApplication {

    public static void main(String[] args) {
        new SpringApplicationBuilder()
                .parent(Services.class)
                .child(ApiOne.class, MainApiApplication.class)
                .run(args);
    }

    @Bean
    public EmbeddedServletContainerFactory servletContainer() {
        return new TomcatEmbeddedServletContainerFactory();
    }

}

Now I want to add another client context (and DispatcherServlet) for my ApiTwo.class configuration. I think I have to do two things:

1. Move the servletContainer (thus the MainApiApplication.class configuration) out of the child context and
2. add a path mapping /one/ -> ApiOne.class and /two/ ApiTwo.class

What is the spring boot way to do it?

Solution

As @josh-ghiloni already said, you need to register a ServletRegistrationBean for every isolated web context you want to create. You need to create an application context from a xml or java config class. You can use @Import and @ComponentScan annotation to add shared services to the parent context. Here is an example:

import org.springframework.boot.SpringApplication;
import org.springframework.boot.context.embedded.ServletRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
import org.springframework.web.context.support.XmlWebApplicationContext;
import org.springframework.web.servlet.DispatcherServlet;


//@ComponentScan({"..."})
//@Import({})
public class Starter {

    public static void main(String[] args) throws Exception {
        SpringApplication.run(Starter.class, args);
    }

    @Bean
    public ServletRegistrationBean apiV1() {
        DispatcherServlet dispatcherServlet = new DispatcherServlet();

        XmlWebApplicationContext applicationContext = new XmlWebApplicationContext();
        applicationContext.setConfigLocation("classpath:/META-INF/spring/webmvc-context.xml");
        dispatcherServlet.setApplicationContext(applicationContext);

        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(dispatcherServlet, "/api/1/*");
        servletRegistrationBean.setName("api-v1");

        return servletRegistrationBean;
    }

    @Bean
    public ServletRegistrationBean apiV2() {
        DispatcherServlet dispatcherServlet = new DispatcherServlet();

        AnnotationConfigWebApplicationContext applicationContext = new AnnotationConfigWebApplicationContext();
        applicationContext.register(ResourceConfig.class);
        dispatcherServlet.setApplicationContext(applicationContext);

        ServletRegistrationBean servletRegistrationBean = new ServletRegistrationBean(dispatcherServlet, "/api/2/*");
        servletRegistrationBean.setName("api-v2");
        return servletRegistrationBean;
    }
}

Answered By - ksokol