UISClientHandlerImpl.java

package eu.europeana.cloud.service.mcs.persistent.uis;

import eu.europeana.cloud.client.uis.rest.CloudException;
import eu.europeana.cloud.client.uis.rest.UISClient;
import eu.europeana.cloud.common.exceptions.ProviderDoesNotExistException;
import eu.europeana.cloud.common.model.CloudId;
import eu.europeana.cloud.common.model.DataProvider;
import eu.europeana.cloud.common.response.ResultSlice;
import eu.europeana.cloud.service.mcs.UISClientHandler;
import eu.europeana.cloud.service.mcs.exception.ProviderNotExistsException;
import eu.europeana.cloud.service.mcs.exception.RecordNotExistsException;
import eu.europeana.cloud.service.mcs.persistent.exception.SystemException;
import eu.europeana.cloud.service.uis.exception.CloudIdDoesNotExistException;
import java.util.Iterator;

import eu.europeana.cloud.service.uis.exception.RecordDoesNotExistException;
import org.springframework.beans.factory.annotation.Autowired;

/**
 * Communicates with Unique Identifier Service using UISClient. Used for
 * checking if cloudIds and providers exists in UIS.
 */
public class UISClientHandlerImpl implements UISClientHandler {

    @Autowired
    private UISClient uisClient;

    /**
     * @inheritDoc
     */
    @Override
    public boolean existsCloudId(String cloudId) {
	boolean result = false;
	try {
	    ResultSlice<CloudId> records = uisClient.getRecordId(cloudId);
	    if (records == null) {
		throw new IllegalStateException("UIS returned null");
	    }
	    if (records.getResults().isEmpty()) {
		throw new IllegalStateException("UIS returned empty list");
	    }

	    Iterator<CloudId> iterator = records.getResults().iterator();
	    while (iterator.hasNext()) {
		CloudId ci = iterator.next();
		if (ci.getId().equals(cloudId)) {
		    result = true;
		    break;
		}
	    }
	    if (!result) {
		throw new IllegalStateException(String.format(
			"Cloud id %s not on the list returned by UIS", cloudId));
	    }
	} catch (CloudException ex) {
	    if (ex.getCause() instanceof CloudIdDoesNotExistException) {
		result = false;
	    } else {
		throw new SystemException(ex);
	    }
	}
	return result;
    }

	@Override
	public CloudId getCloudIdFromProviderAndLocalId(String providerId, String localId) throws ProviderNotExistsException, RecordNotExistsException {
		try {
			return uisClient.getCloudId(providerId,localId);
		} catch (CloudException ex) {
			if (ex.getCause() instanceof RecordDoesNotExistException) {
				throw new RecordNotExistsException(localId, providerId);
			}
			else if (ex.getCause() instanceof ProviderDoesNotExistException) {
				throw new ProviderNotExistsException(ex.getMessage());
			} else {
				throw new SystemException(ex);
			}
		}
	}


	/**
     * @inheritDoc
     */
    @Override
    public boolean existsProvider(String providerId) {
	DataProvider result;
	try {
	    result = uisClient.getDataProvider(providerId);
	} catch (CloudException e) {
	    if (e.getCause() instanceof ProviderDoesNotExistException) {
		result = null;
	    } else {
		throw new SystemException(e);
	    }
	}
	return result != null;
    }

    /**
     * @inheritDoc
     */
    @Override
    public DataProvider getProvider(String providerId) {
	DataProvider result;
	try {
	    result = uisClient.getDataProvider(providerId);
	} catch (CloudException e) {
	    if (e.getCause() instanceof ProviderDoesNotExistException) {
		return null;
	    } else {
		throw new SystemException(e);
	    }
	}
	return result;
    }
}