package com.mycompany.myapp.config;
import com.codahale.metrics.MetricRegistry;
import com.codahale.metrics.servlet.InstrumentedFilter;
import com.codahale.metrics.servlets.MetricsServlet;
import com.mycompany.myapp.web.filter.CachingHttpHeadersFilter;
import com.mycompany.myapp.web.filter.StaticResourcesProductionFilter;
import com.mycompany.myapp.web.filter.gzip.GZipServletFilter;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.boot.autoconfigure.AutoConfigureAfter;
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.*;
import java.util.Arrays;
import java.util.EnumSet;
import java.util.HashMap;
import java.util.Map;
/**
* Configuration of web application with Servlet 3.0 APIs.
*/
@Configuration
@AutoConfigureAfter(CacheConfiguration.class)
public class WebConfigurer implements ServletContextInitializer {
private final Logger log = LoggerFactory.getLogger(WebConfigurer.class);
@Inject
private Environment env;
@Inject
private MetricRegistry metricRegistry;
@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);
initMetrics(servletContext, disps);
if (env.acceptsProfiles(Constants.SPRING_PROFILE_PRODUCTION)) {
initCachingHttpHeadersFilter(servletContext, disps);
initStaticResourcesProductionFilter(servletContext, disps);
}
initGzipFilter(servletContext, disps);
if (env.acceptsProfiles(Constants.SPRING_PROFILE_DEVELOPMENT)) {
initH2Console(servletContext);
}
log.info("Web application fully configured");
}
/**
* Initializes the GZip filter.
*/
private void initGzipFilter(ServletContext servletContext, EnumSet<DispatcherType> disps) {
log.debug("Registering GZip Filter");
FilterRegistration.Dynamic compressingFilter = servletContext.addFilter("gzipFilter", new GZipServletFilter());
Map<String, String> parameters = new HashMap<>();
compressingFilter.setInitParameters(parameters);
compressingFilter.addMappingForUrlPatterns(disps, true, "*.css");
compressingFilter.addMappingForUrlPatterns(disps, true, "*.json");
compressingFilter.addMappingForUrlPatterns(disps, true, "*.html");
compressingFilter.addMappingForUrlPatterns(disps, true, "*.js");
compressingFilter.addMappingForUrlPatterns(disps, true, "/app/rest/*");
compressingFilter.addMappingForUrlPatterns(disps, true, "/metrics/*");
compressingFilter.setAsyncSupported(true);
}
/**
* Initializes the static resources production Filter.
*/
private void initStaticResourcesProductionFilter(ServletContext servletContext,
EnumSet<DispatcherType> disps) {
log.debug("Registering static resources production Filter");
FilterRegistration.Dynamic staticResourcesProductionFilter =
servletContext.addFilter("staticResourcesProductionFilter",
new StaticResourcesProductionFilter());
staticResourcesProductionFilter.addMappingForUrlPatterns(disps, true, "/");
staticResourcesProductionFilter.addMappingForUrlPatterns(disps, true, "/index.html");
staticResourcesProductionFilter.addMappingForUrlPatterns(disps, true, "/images/*");
staticResourcesProductionFilter.addMappingForUrlPatterns(disps, true, "/fonts/*");
staticResourcesProductionFilter.addMappingForUrlPatterns(disps, true, "/scripts/*");
staticResourcesProductionFilter.addMappingForUrlPatterns(disps, true, "/styles/*");
staticResourcesProductionFilter.addMappingForUrlPatterns(disps, true, "/views/*");
staticResourcesProductionFilter.setAsyncSupported(true);
}
/**
* Initializes the cachig HTTP Headers Filter.
*/
private void initCachingHttpHeadersFilter(ServletContext servletContext,
EnumSet<DispatcherType> disps) {
log.debug("Registering Cachig HTTP Headers Filter");
FilterRegistration.Dynamic cachingHttpHeadersFilter =
servletContext.addFilter("cachingHttpHeadersFilter",
new CachingHttpHeadersFilter());
cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/images/*");
cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/fonts/*");
cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/scripts/*");
cachingHttpHeadersFilter.addMappingForUrlPatterns(disps, true, "/styles/*");
cachingHttpHeadersFilter.setAsyncSupported(true);
}
/**
* Initializes Metrics.
*/
private void initMetrics(ServletContext servletContext, EnumSet<DispatcherType> disps) {
log.debug("Initializing Metrics registries");
servletContext.setAttribute(InstrumentedFilter.REGISTRY_ATTRIBUTE,
metricRegistry);
servletContext.setAttribute(MetricsServlet.METRICS_REGISTRY,
metricRegistry);
log.debug("Registering Metrics Filter");
FilterRegistration.Dynamic metricsFilter = servletContext.addFilter("webappMetricsFilter",
new InstrumentedFilter());
metricsFilter.addMappingForUrlPatterns(disps, true, "/*");
metricsFilter.setAsyncSupported(true);
log.debug("Registering Metrics Servlet");
ServletRegistration.Dynamic metricsAdminServlet =
servletContext.addServlet("metricsServlet", new MetricsServlet());
metricsAdminServlet.addMapping("/metrics/metrics/*");
metricsAdminServlet.setAsyncSupported(true);
metricsAdminServlet.setLoadOnStartup(2);
}
/**
* Initializes H2 console
*/
private void initH2Console(ServletContext servletContext) {
log.debug("Initialize H2 console");
ServletRegistration.Dynamic h2ConsoleServlet = servletContext.addServlet("H2Console", new org.h2.server.web.WebServlet());
h2ConsoleServlet.addMapping("/console/*");
h2ConsoleServlet.setLoadOnStartup(1);
}
}