Allowed external http and https targets for LinkNodes

    public enum ProtocolType {

        // Please keep the URIs in this enum UNIQUE!

        // will add a unit test to check this

        // added a unit test to check this

        HTTPGET("ivo://ivoa.net/vospace/core#httpget", "http"),

        HTTPSGET("ivo://ivoa.net/vospace/core#httpsget", "https"),

        HTTPPUT("ivo://ivoa.net/vospace/core#httpput", "http"),

import it.inaf.ia2.aa.ServletRapClient;

import it.inaf.ia2.aa.data.User;

import it.inaf.oats.vospace.UriService.ProtocolType;

import it.inaf.oats.vospace.datamodel.NodeProperties;

import it.inaf.oats.vospace.datamodel.NodeUtils;

import it.inaf.oats.vospace.datamodel.Views;

import it.inaf.oats.vospace.persistence.NodeDAO;

import it.inaf.oats.vospace.persistence.model.Location;

import it.inaf.oats.vospace.persistence.model.LocationType;

import java.util.List;

import java.util.Optional;

import java.util.stream.Collectors;

import javax.servlet.http.HttpServletRequest;

import net.ivoa.xml.uws.v1.JobSummary;

import net.ivoa.xml.vospace.v2.ContainerNode;

        return job;

    }

    @Test

    public void testProtocolType() {

        List<ProtocolType> pts = List.of(ProtocolType.values());

        int distinctUris = 

                pts.stream().map(pt -> pt.getUri()).distinct().collect(Collectors.toList()).size();

        assertEquals(pts.size(), distinctUris);

    }

}