net.bluemix.todo.store.ToDoStoreFactory.java Source code

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Here is the source code for net.bluemix.todo.store.ToDoStoreFactory.java

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/*
 * Copyright IBM Corp. 2014
 *
 * 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 net.bluemix.todo.store;

import java.util.List;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.WebTarget;

import net.bluemix.todo.connector.CloudantServiceInfo;

import org.glassfish.jersey.client.authentication.HttpAuthenticationFeature;
import org.springframework.cloud.Cloud;
import org.springframework.cloud.CloudException;
import org.springframework.cloud.CloudFactory;
import org.springframework.cloud.service.ServiceInfo;
import org.springframework.cloud.service.common.MongoServiceInfo;

import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.MongoClient;

/**
 * Creates an instance of the a {@link ToDoStore} to use.
 */
public class ToDoStoreFactory {
    private static final int PERIOD = 30; //in seconds
    private static ToDoStore instance;
    private static CloudFactory cloudFactory;
    private static ScheduledExecutorService exec = Executors.newSingleThreadScheduledExecutor();

    /**
     * Gets an instance of {@link ToDoStore}. 
     * @return A {@link ToDoStore}.
     */
    public static ToDoStore getInstance() throws ToDoStoreException {
        if (instance == null) {
            cloudFactory = new CloudFactory();
            try {
                Cloud cloud = cloudFactory.getCloud();
                List<ServiceInfo> infos = cloud.getServiceInfos();
                MongoServiceInfo mongoInfo = null;
                CloudantServiceInfo cloudantInfo = null;
                for (ServiceInfo info : infos) {
                    if (info.getId().equals("todo-mongo-db")) {
                        mongoInfo = (MongoServiceInfo) info;
                        break;
                    }
                    if (info.getId().equals("todo-couch-db")) {
                        cloudantInfo = (CloudantServiceInfo) info;
                        break;
                    }
                }
                if (mongoInfo != null) {
                    instance = new MongoStore(getCollection(mongoInfo));
                } else if (cloudantInfo != null) {
                    instance = new CloudantStore(getWebTarget(cloudantInfo));
                } else {
                    instance = new InMemoryStore();
                }
            } catch (CloudException e) {
                instance = new InMemoryStore();
            }
            exec.scheduleAtFixedRate(new Cleanup(), PERIOD, PERIOD, TimeUnit.SECONDS);
        }
        return instance;
    }

    private static DBCollection getCollection(MongoServiceInfo info) throws ToDoStoreException {
        MongoClient client;
        try {
            client = new MongoClient(info.getHost(), info.getPort());
            DB db = client.getDB(info.getDatabase());
            boolean auth = db.authenticate(info.getUserName(), info.getPassword().toCharArray());
            if (!auth) {
                throw new ToDoStoreException("Could not authenticate to Mongo DB.");
            }
            return db.getCollection("todos");
        } catch (Exception e) {
            throw new ToDoStoreException("Error creating Mongo DB client.", e);
        }
    }

    private static WebTarget getWebTarget(CloudantServiceInfo info) {
        HttpAuthenticationFeature basicAuthFeature = HttpAuthenticationFeature.basic(info.getUsername(),
                info.getPassword());
        Client client = ClientBuilder.newClient().register(basicAuthFeature);
        return client.target(info.getUrl());
    }
}