WebConfigurer.java

package ee.esutoniagodesu.config;

import ee.esutoniagodesu.web.filter.CachingHttpHeadersFilter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.context.embedded.ConfigurableEmbeddedServletContainer;
import org.springframework.boot.context.embedded.EmbeddedServletContainerCustomizer;
import org.springframework.boot.context.embedded.MimeMappings;
import org.springframework.boot.context.embedded.ServletContextInitializer;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.env.Environment;

import javax.inject.Inject;
import javax.servlet.DispatcherType;
import javax.servlet.FilterRegistration;
import javax.servlet.ServletContext;
import javax.servlet.ServletException;
import java.util.Arrays;
import java.util.EnumSet;

/**
 * Configuration of web application with Servlet 3.0 APIs.
 */
@Configuration
public class WebConfigurer implements ServletContextInitializer, EmbeddedServletContainerCustomizer {

    private static final Logger log = LoggerFactory.getLogger(WebConfigurer.class);

    @Inject
    private Environment env;

    @Override
    public void onStartup(ServletContext servletContext) throws ServletException {
        log.info("Web application configuration, using profiles: {}", Arrays.toString(env.getActiveProfiles()));
        EnumSet<DispatcherType> disps = EnumSet.of(DispatcherType.REQUEST, DispatcherType.FORWARD, DispatcherType.ASYNC);

        if (env.acceptsProfiles(Profiles.SPRING_PROFILE_PROD)) {
            initCachingHttpHeadersFilter(servletContext, disps);
        }
        log.info("Web application fully configured");
    }

    /**
     * Set up Mime types.
     */
    @Override
    public void customize(ConfigurableEmbeddedServletContainer container) {
        MimeMappings mappings = new MimeMappings(MimeMappings.DEFAULT);
        // IE issue, see https://github.com/jhipster/generator-jhipster/pull/711
        mappings.add("html", "text/html;charset=utf-8");
        // CloudFoundry issue, see https://github.com/cloudfoundry/gorouter/issues/64
        mappings.add("json", "text/html;charset=utf-8");
        container.setMimeMappings(mappings);
    }

    /**
     * Initializes the cachig HTTP Headers Filter.
     */
    private void initCachingHttpHeadersFilter(ServletContext servletContext,
                                              EnumSet<DispatcherType> disps) {
        log.debug("Registering Caching HTTP Headers Filter");
        FilterRegistration.Dynamic cachingHttpHeadersFilter =
            servletContext.addFilter("cachingHttpHeadersFilter",
                new CachingHttpHeadersFilter(env));

        cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/assets/*");
        cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/scripts/*");
        cachingHttpHeadersFilter.setAsyncSupported(true);
    }
}