io.mapping.api.billsplit.guice.BillSplitServletModule.java Source code

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Here is the source code for io.mapping.api.billsplit.guice.BillSplitServletModule.java

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/*
 * Copyright 2013 Jacob Miles Prystowsky
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package io.mapping.api.billsplit.guice;

import com.fasterxml.jackson.jaxrs.json.JacksonJsonProvider;
import com.google.api.client.googleapis.auth.oauth2.GoogleClientSecrets;
import com.google.api.client.http.HttpTransport;
import com.google.api.client.http.javanet.NetHttpTransport;
import com.google.api.client.json.jackson2.JacksonFactory;
import com.google.inject.Provides;
import com.google.inject.Scopes;
import com.google.inject.Singleton;
import com.google.inject.servlet.ServletModule;
import com.sun.jersey.guice.spi.container.servlet.GuiceContainer;
import io.mapping.api.billsplit.oauth2.BigIntegerStateGenerator;
import io.mapping.api.billsplit.oauth2.GoogleOAuth2Helper;
import io.mapping.api.billsplit.oauth2.OAuth2Helper;
import io.mapping.api.billsplit.oauth2.StateGenerator;
import io.mapping.api.billsplit.reflection.AutoPackageNameProviderAlgorithm;
import io.mapping.api.billsplit.reflection.PackageNameProvider;
import io.mapping.api.billsplit.reflection.PackageNameProviderAlgorithm;
import io.mapping.api.billsplit.reflection.RuntimePackageNameProvider;
import io.mapping.api.billsplit.resources.AuthResource;
import io.mapping.api.billsplit.resources.BillSetResource;
import io.mapping.api.billsplit.resources.ConnectGoogleResource;
import io.mapping.api.billsplit.resources.UserResource;
import io.mapping.api.billsplit.sessions.SessionAttributes;
import io.mapping.api.billsplit.sessions.SessionAttributesImpl;
import io.mapping.api.billsplit.sessions.SessionUserProvider;
import io.mapping.api.billsplit.sessions.SessionUserProviderImpl;
import io.mapping.api.billsplit.settings.JsonFileSettingsReader;
import io.mapping.api.billsplit.settings.SettingsReader;

import javax.persistence.EntityManagerFactory;
import javax.persistence.Persistence;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.Reader;
import java.util.HashMap;
import java.util.Map;

public class BillSplitServletModule extends ServletModule {
    private static final String FILE_SETTINGS = "/settings.json";
    private static final String FILE_GOOGLE_OAUTH = "/google_oauth.json";

    private static final SettingsReader SETTINGS_READER = new JsonFileSettingsReader.Builder()
            .fileName(FILE_SETTINGS).build();

    private static final EntityManagerFactory ENTITY_MANAGER_FACTORY = Persistence
            .createEntityManagerFactory(SETTINGS_READER.getSettings().getPersistenceUnitName());

    private static final JacksonFactory JSON_FACTORY = new JacksonFactory();

    @Override
    protected void configureServlets() {
        /**
         * Bind resources (i.e., backings to RESTful endpoints)
         */
        bind(AuthResource.class);
        bind(BillSetResource.class);
        bind(ConnectGoogleResource.class);
        bind(UserResource.class);

        /**
         * Perform dependency injection (DI)
         */
        bind(HttpTransport.class).to(NetHttpTransport.class).in(Scopes.SINGLETON);

        bind(StateGenerator.class).to(BigIntegerStateGenerator.class).in(Scopes.SINGLETON);
        bind(OAuth2Helper.class).to(GoogleOAuth2Helper.class).in(Scopes.SINGLETON);
        bind(PackageNameProvider.class).to(RuntimePackageNameProvider.class).in(Scopes.SINGLETON);
        bind(PackageNameProviderAlgorithm.class).to(AutoPackageNameProviderAlgorithm.class).in(Scopes.SINGLETON);
        bind(SessionAttributes.class).to(SessionAttributesImpl.class).in(Scopes.SINGLETON);
        bind(SessionUserProvider.class).to(SessionUserProviderImpl.class).in(Scopes.SINGLETON);

        /**
         * Hook in Jackson
         */
        bind(JacksonJsonProvider.class).in(Scopes.SINGLETON);

        /**
         * Serve it up, boss!
         * Set the com.sun.jersey.spi.container.ContainerResponseFilters parameter to our class to indicate
         * that it should handle {@link com.sun.jersey.spi.container.ContainerResponseFilter}s.
         *
         * Semicolon-delineate multiple items in a list.
         */
        Map<String, String> params = new HashMap<>();
        params.put("com.sun.jersey.spi.container.ContainerResponseFilters",
                "io.mapping.api.billsplit.filters.CORSFilter");
        serve("/*").with(GuiceContainer.class, params);
    }

    @Provides
    @Singleton
    EntityManagerFactory provideEntityManagerFactory() {
        return ENTITY_MANAGER_FACTORY;
    }

    @Provides
    @Singleton
    GoogleClientSecrets provideGoogleClientSecrets() {
        GoogleClientSecrets googleClientSecrets = null;

        try {
            Reader reader = new InputStreamReader(this.getClass().getResourceAsStream(FILE_GOOGLE_OAUTH));
            googleClientSecrets = GoogleClientSecrets.load(JSON_FACTORY, reader);
        } catch (IOException e) {
            e.printStackTrace();
        }

        return googleClientSecrets;
    }

    @Provides
    @Singleton
    SettingsReader provideSettingsReader() {
        return SETTINGS_READER;
    }
}