com.sandeep.prototypes.person.PersonApplication.java Source code

Introduction

Here is the source code for com.sandeep.prototypes.person.PersonApplication.java

Source

package com.sandeep.prototypes.person;

import io.dropwizard.Application;
import io.dropwizard.setup.Bootstrap;
import io.dropwizard.setup.Environment;

import java.net.MalformedURLException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.EnumSet;

import javax.servlet.DispatcherType;
import javax.servlet.FilterRegistration;

import org.apache.commons.configuration.ConfigurationException;
import org.eclipse.jetty.servlets.CrossOriginFilter;

import com.fasterxml.jackson.annotation.JsonInclude;
import com.hubspot.dropwizard.guice.GuiceBundle;
import com.netflix.config.DynamicConfiguration;
import com.netflix.config.DynamicPropertyFactory;
import com.netflix.config.FixedDelayPollingScheduler;
import com.netflix.config.PolledConfigurationSource;
import com.netflix.config.sources.URLConfigurationSource;
import com.sandeep.prototypes.person.config.PersonConfiguration;
import com.sandeep.prototypes.person.guice.PersonGuiceModule;
import com.wordnik.swagger.jaxrs.config.BeanConfig;
import com.wordnik.swagger.jaxrs.listing.ApiDeclarationProvider;
import com.wordnik.swagger.jaxrs.listing.ApiListingResourceJSON;
import com.wordnik.swagger.jaxrs.listing.ResourceListingProvider;

/**
 * <p>
 * The prototype application pulls together models and configuration which makes up the complete
 * application
 * </p>
 * 
 * @author Sandeep Nayak
 *
 */
public class PersonApplication extends Application<PersonConfiguration> {

    private static final String CORS_METHODS = "POST,GET,DELETE,PUT,OPTIONS";
    private static final String CORS_HEADERS = "Content-Type,Authorization,X-Requested-With,Content-Length,Accept,Origin";
    private static final String CORS_FILTER = "CORS";
    private static final String PERSON_APP = "Person Application";

    @Override
    public String getName() {
        return PERSON_APP;
    }

    /**
     * <p>
     * Main entry point into the application
     * </p>
     * 
     * @param args the arguments to the application
     * @throws Exception we do not handle exceptions just throw them back
     */
    public static void main(String args[]) throws Exception {
        new PersonApplication().run(args);
    }

    @Override
    /**
     * <p>
     * Initializes the application with <a href="https://github.com/Netflix/archaius/wiki/Users-Guide">Archaius</a>
     * for configuration management and Guice for dependency injection.
     * 
     * </p>
     * 
     * @param bootStrapConfiguration 
     */
    public void initialize(Bootstrap<PersonConfiguration> bootStrapConfiguration) {
        try {
            DynamicPropertyFactory.initWithConfigurationSource(getPropertiesConfiguration());
        } catch (Throwable e) {
            throw new IllegalStateException(e);
        }
        GuiceBundle<PersonConfiguration> guiceBundle = GuiceBundle.<PersonConfiguration>newBuilder()
                .addModule(new PersonGuiceModule())
                .enableAutoConfig("com.sandeep.prototypes.person", "com.sandeep.prototypes.person.dependency",
                        "com.sandeep.prototypes.person.entity", "com.sandeep.prototypes.person.config",
                        "com.sandeep.prototypes.person.resources", "com.sandeep.prototypes.person.guice")
                .setConfigClass(PersonConfiguration.class).build();
        bootStrapConfiguration.addBundle(guiceBundle);
    }

    /**
     * <p>
     * In this method we are initializing the Archaius configuration manager to load configurations
     * from a properties file.
     * 
     * The steps to initializing the configuration is as follows
     * <ul>
     * <li>Create a configuration source for the file which contains the properties</li>
     * <li>Create a dynamic configuration around the source so that the source is polled, the polling
     * can be configured to be at a different frequency</li>
     * </ul>
     * 
     * @return DynamicConfiguration
     * @throws ConfigurationException
     * @throws MalformedURLException
     */
    private DynamicConfiguration getPropertiesConfiguration() throws ConfigurationException, MalformedURLException {
        String userHome = System.getProperty("user.home");
        Path properties = Paths.get(userHome, "config-root", "person", "person.properties");
        PolledConfigurationSource polledSource = new URLConfigurationSource(properties.toUri().toURL());
        return new DynamicConfiguration(polledSource, new FixedDelayPollingScheduler());
    }

    @Override
    public void run(PersonConfiguration configuration, Environment environment) throws Exception {
        // We need CORS enabled so that swagger can access the documentation endpoint and we can
        // retrieve the swagger compliant json
        FilterRegistration.Dynamic cors = environment.servlets().addFilter(CORS_FILTER, CrossOriginFilter.class);
        cors.addMappingForUrlPatterns(EnumSet.allOf(DispatcherType.class), true, "/*");
        cors.setInitParameter(CrossOriginFilter.ACCESS_CONTROL_ALLOW_ORIGIN_HEADER, "*");
        cors.setInitParameter(CrossOriginFilter.ALLOWED_HEADERS_PARAM, CORS_HEADERS);
        cors.setInitParameter(CrossOriginFilter.ALLOWED_METHODS_PARAM, CORS_METHODS);
        cors.setInitParameter("allowCredentials", "true");

        environment.jersey().register(new ApiListingResourceJSON());
        environment.jersey().register(new ApiDeclarationProvider());
        environment.jersey().register(new ResourceListingProvider());

        // environment.jersey().register(new PersonResource(configuration.getMessage()));
        environment.getObjectMapper().setSerializationInclusion(JsonInclude.Include.NON_NULL);

        BeanConfig config = new BeanConfig();
        config.setTitle(configuration.getApplicationTitle());
        config.setDescription(configuration.getApplicationDescription());
        config.setTermsOfServiceUrl(configuration.getApplicationTosUrl());
        config.setContact(configuration.getApplicationContact());
        config.setLicense(configuration.getLicense());
        config.setVersion(configuration.getVersion());
        config.setBasePath(configuration.getDocsPath());
        config.setResourcePackage("com.sandeep.prototypes.person.resources");
        config.setScan(true);

    }
}