D-Net

package eu.dnetlib.repo.manager.server.services;

import eu.dnetlib.domain.data.Repository;

import eu.dnetlib.gwt.server.service.SpringGwtRemoteServiceServlet;

import eu.dnetlib.repo.manager.client.services.BrokerService;

import eu.dnetlib.repo.manager.shared.BrokerException;

import eu.dnetlib.repo.manager.shared.RepositoryServiceException;

import eu.dnetlib.repo.manager.shared.Tuple;

import eu.dnetlib.repo.manager.shared.broker.*;

import eu.dnetlib.repos.RepoApi;

import org.apache.log4j.Logger;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.beans.factory.annotation.Value;

import org.springframework.core.ParameterizedTypeReference;

import org.springframework.http.HttpEntity;

import org.springframework.http.HttpMethod;

import org.springframework.http.ResponseEntity;

import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;

import org.springframework.stereotype.Service;

import org.springframework.util.LinkedMultiValueMap;

import org.springframework.util.MultiValueMap;

import org.springframework.web.client.RestClientException;

import org.springframework.web.client.RestTemplate;

import org.springframework.web.util.UriComponentsBuilder;

import javax.servlet.ServletConfig;

import javax.servlet.ServletException;

import java.util.*;

/**

 * Created by stefanos on 10/26/16.

 */

@SuppressWarnings("serial")

@Service("brokerService")

public class BrokerServiceImpl extends SpringGwtRemoteServiceServlet implements BrokerService {

    private static final Logger LOGGER = Logger

            .getLogger(BrokerServiceImpl.class);

    @Autowired

    private RepoApi repoAPI;

    @Override

    public void init(ServletConfig config) throws ServletException {

        super.init(config);

        LOGGER.info("broker service init");

    }

    @Value("${services.broker.url}:${services.broker.port}/${services.broker.path}")

    private String apiPath;

    /**

     * @param datasourceName the name of the data source

     * @return a list of BrowseEvent entries for that datasource

     * @throws BrokerException containing the error code from the server

     * @author stefanos

     */

    @Override

    public List<BrowseEntry> getTopicsForDatasource(String datasourceName) throws BrokerException {

        final String service = "/topicsForDatasource";

        //build the uri params

        UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(apiPath + service)

                .queryParam("ds", datasourceName);

        //create new template engine

        RestTemplate template = new RestTemplate();

        template.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

        ResponseEntity<List<BrowseEntry>> resp;

        try {

            //communicate with endpoint

            resp = template.exchange(

                    builder.build().encode().toUri(),

                    HttpMethod.GET,

                    null,

                    new ParameterizedTypeReference<List<BrowseEntry>>() {

                    });

        } catch (RestClientException e) {

            throw new BrokerException(e);

        }

        return resp.getBody();

    }

    /**

     * @param datasourceName the name of the datasource

     * @param topic          the name of the topic to filter

     * @param page           the page number

     * @return an Events page with a constant 50 max number of entires

     * @throws BrokerException containing the error code from the server

     */

    @Override

    public EventsPage showEvents(String datasourceName, String topic, long page) throws BrokerException {

        final String service = "/showEvents";

        //build the uri params

        UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(apiPath + service)

                .queryParam("ds", datasourceName)

                .queryParam("topic", topic)

                .queryParam("page", page);

        //create new template engine

        RestTemplate template = new RestTemplate();

        template.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

        ResponseEntity<EventsPage> resp;

        try {

            //communicate with endpoint

            resp = template.exchange(

                    builder.build().encode().toUri(),

                    HttpMethod.GET,

                    null,

                    new ParameterizedTypeReference<EventsPage>() {

                    });

        } catch (RestClientException e) {

            throw new BrokerException(e);

        }

        return resp.getBody();

    }

    /**

     * @param advQueryObject a pojo class containing the filter parameters

     * @param page           the number of the page

     * @param pageSize       the page size

     * @return

     * @throws BrokerException

     */

    @Override

    public EventsPage advancedShowEvents(AdvQueryObject advQueryObject, long page, long pageSize) throws BrokerException {

        final String service = "/events/{page}/{pageSize}";

        // URI (URL) parameters

        Map<String, Long> uriParams = new HashMap<>();

        uriParams.put("page", page);

        uriParams.put("pageSize", pageSize);

        //build the uri params

        UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(apiPath + service);

        //Header info

        MultiValueMap<String, String> headers = new LinkedMultiValueMap<>();

        headers.add("Content-Type", "application/json");

        advQueryObject.setPage(page);

        HttpEntity<AdvQueryObject> entity = new HttpEntity<>(advQueryObject, headers);

        //create new template engine

        RestTemplate template = new RestTemplate();

        template.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

        ResponseEntity<EventsPage> resp;

        try {

            //communicate with endpoint

            resp = template.exchange(

                    builder.buildAndExpand(uriParams).encode().toUri(),

                    HttpMethod.POST,

                    entity,

                    new ParameterizedTypeReference<EventsPage>() {

                    }

            );

        } catch (RestClientException e) {

            throw new BrokerException(e);

        }

        return resp.getBody();

    }

    @Override

    public DatasourcesBroker getDatasourcesOfUser(String userEmail, boolean includeShared, boolean includeByOthers) throws BrokerException {

        DatasourcesBroker ret = new DatasourcesBroker();

        try {

            LOGGER.debug("In getDatasourcesOfUser");

            //set for user

            ret.setDatasourcesOfUser(getDatasourcesOfUserType(this.repoAPI.getRepositoriesOfUser(userEmail, false)));

            //set for shared

            if (includeShared) {

                //TODO whatever nikonas was saying

                List<String> sharedDatasourceIds = new ArrayList<String>();

                ret.setSharedDatasources(getDatasourcesOfUserType(this.repoAPI.getReposByIds(sharedDatasourceIds)));

            }

            //set others

            if (includeByOthers) {

                ret.setDatasourcesOfOthers(getDatasourcesOfUserType(this.repoAPI.getRepositoriesOfUser(userEmail, true)));

            }

        } catch (RepositoryServiceException e) {

            e.printStackTrace();

            throw new BrokerException(e);

        } catch (Exception e) {

            e.printStackTrace();

        }

        return ret;

    }

    @Override

    public Map<String, List<SimpleSubscriptionDesc>> getSubscriptionsOfUser(String userEmail) throws BrokerException {

        final String service = "/subscriptions";

        //build the uri params

        UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(apiPath + service)

                .queryParam("email", userEmail);

        //create new template engine

        RestTemplate template = new RestTemplate();

        template.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

        ResponseEntity<Map<String, List<SimpleSubscriptionDesc>>> resp;

        try {

            //communicate with endpoint

            resp = template.exchange(

                    builder.build().encode().toUri(),

                    HttpMethod.GET,

                    null,

                    new ParameterizedTypeReference<Map<String, List<SimpleSubscriptionDesc>>>() {

                    });

        } catch (RestClientException e) {

            throw new BrokerException(e);

        }

        return resp.getBody();

    }

    @Override

    public Subscription subscribe(OpenaireSubscription obj) throws BrokerException {

        final String service = "/subscribe";

        //build the uri params

        UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl(apiPath + service);

        //Header info

        MultiValueMap<String, String> headers = new LinkedMultiValueMap<>();

        headers.add("Content-Type", "application/json");

        HttpEntity<OpenaireSubscription> entity = new HttpEntity<>(obj, headers);

        //create new template engine

        RestTemplate template = new RestTemplate();

        template.getMessageConverters().add(new MappingJackson2HttpMessageConverter());

        ResponseEntity<Subscription> resp;

        try {

            //communicate with endpoint

            resp = template.exchange(

                    builder.build().encode().toUri(),

                    HttpMethod.GET,

                    entity,

                    new ParameterizedTypeReference<Subscription>() {

                    });

        } catch (RestClientException e) {

            throw new BrokerException(e);

        }

        return resp.getBody();

    }

    @Override

    public void unsubscribe(String subscriptionId) throws BrokerException {

        throw new BrokerException(new Exception("Not implemented"));

    }

    /**

     * Helper class to aggregate the datasources topic sizes by datasource name.

     *

     * @param repositories to be aggregated

     * @return a List of BrowseEntry with the official name and the number of topics for each repo and logo url

     * @throws BrokerException

     */

    private List<Tuple<BrowseEntry, String>> getDatasourcesOfUserType(List<Repository> repositories) throws BrokerException {

        //get user entries

        LOGGER.debug("getDatasourcesOfUserType : " + repositories.size());

        List<Tuple<BrowseEntry, String>> entries = new ArrayList<>();

        for (Repository repo : repositories) {

            BrowseEntry temp = new BrowseEntry();

            temp.setValue(repo.getOfficialName());

            temp.setSize(new Long(0));

            for (BrowseEntry e : this.getTopicsForDatasource(repo.getOfficialName())) {

                temp.setSize(temp.getSize() + e.getSize());

            }

            Tuple<BrowseEntry, String> tup = new Tuple<>(temp, repo.getLogoUrl());

            entries.add(tup);

        }

        // sort the collection by the second field of the tuple which is size

        Collections.sort(entries, new Comparator<Tuple<BrowseEntry, String>>() {

            @Override

            public int compare(Tuple<BrowseEntry, String> e1, Tuple<BrowseEntry, String> e2) {

                return (int) (e2.getFirst().getSize().longValue() - e1.getFirst().getSize().longValue());

            }

        });

        return entries;

    }

}